Journal of Perinatology (2014) 34, 186–191 & 2014 Nature America, Inc. All rights reserved 0743-8346/14 www.nature.com/jp
ORIGINAL ARTICLE
Placental pathology, first-trimester biomarkers and adverse pregnancy outcomes AO Odibo1, KR Patel2, A Spitalnik1, L Odibo1 and P Huettner2 OBJECTIVE: We investigated the relationship between placental pathological findings in pregnancies with adverse pregnancy outcomes and first-trimester serum analytes and uterine artery Doppler results. STUDY DESIGN: This is a secondary analysis of a prospective study of first-trimester screening for adverse pregnancy outcomes, including preterm birth (PTB (deliveryo37 weeks)), pre-eclampsia (PE), gestational hypertension, and small for gestational age (SGA) infants (birth weight o10th percentile). We compared the mean levels of serum analytes (pregnancy-associated plasma protein A (PAPP-A), placental protein 13 (PP13), a-disintegrin and metalloproteinase 12 (ADAM12), placental growth factor (PLGF)) and uterine artery Doppler pulsatility index (UADPI) obtained between 11 and 14 weeks gestation in cases with adverse outcomes and abnormal placental histology to a control group without adverse outcome or abnormal placental pathology. Placental findings were classified as: lesions of maternal under perfusion, lesions causing reduced placental reserve, infections/inflammatory lesions, and fetal vascular lesions. RESULT: Among 193 cases, lesions of maternal under perfusion were seen in 50 cases (25.9%), lesions causing reduced placental reserve in 63 cases (32.8%), infection/inflammation in 65 cases (34.2%) and fetal vascular lesions in 23 cases (11.9%). There were 123 pregnancies with no adverse pregnancy outcome or placental lesion used as controls. Pregnancies with PE had a significant association with lesions of maternal under perfusion (P ¼ 0.005) and placental infection/inflammation (P ¼ 0.003). Significant differences were seen in mean levels of PAPP-A, ADAM12 and PLGF in cases with PE, PTB and SGA with specific placental histological findings when compared with controls. UADPI was not significantly different between the cases with adverse pregnancy outcomes and abnormal histology. CONCLUSION: Our findings provide evidence linking placental pathology with suboptimal secretion of analytes in the first trimester in pregnancies with adverse outcomes, especially PE. Journal of Perinatology (2014) 34, 186–191; doi:10.1038/jp.2013.176; published online 16 January 2014 Keywords: placental pathology; first-trimester; serum analytes; adverse pregnancy outcomes
INTRODUCTION Recent reports suggest the potential role of placental proteins, including placental protein 13 (PP13) and pregnancy-associated plasma protein A (PAPP-A), in identifying pregnancies at risk for later development of pre-eclampsia (PE) and preterm birth (PTB).1–8 PPP13 is a member of the galectin family produced by the syncytiotrophoblast3 and is thought to be involved in placental implantation and vascular remodeling.4 Reduced levels of PP13 mRNA levels have been reported in the placentas of women who developed preterm PE.7 In addition, numerous studies have documented that placental growth factor (PLGF) concentration in the first trimester is reduced in women who go on to develop PE and fetal growth restriction.9–10 In addition, our group in previous studies has shown an association between low levels of a-disintegrin and metalloproteinase 12 (ADAM12) in pregnancies with PE and PTB.8,11 Although the exact mechanisms resulting in abnormal secretion of these placental proteins are not clearly understood, some biologically feasible explanations have been proposed. These include reduced placental size or defective syncytiotrophoblast formation resulting in reduced production of placenta-derived proteins, such as PAPP-A12; and hypoxia-reoxygenation induced increased secretion of pro-inflammatory cytokines, such as tumor
necrosis factor a and interleukin-1b, and anti-angiogenic factors, such as the soluble receptor for vascular endothelial growth factor 1.13–15 Placental pathological studies indicate that PE or fetal growth restriction resulting in preterm delivery before 34 weeks have high rates of thrombotic placental pathological findings of the villous trees.16 In contrast, the placentas from term pregnancies with PE and/or fetal growth restriction demonstrate either normal or minimal pathological findings.17 Doppler studies also suggest that preterm PE and fetal growth restriction are associated with defective invasion of the spiral arteries, whereas the spiral artery defect has a much smaller role in cases nearer term.18 The aim of this study is to investigate the hypothesis that the relationship between adverse pregnancy outcomes (APO) and first-trimester serum analytes and uterine artery Doppler results are secondary to underlying specific placental lesions.
METHODS This is a secondary analysis of a prospective study of first-trimester screening for adverse pregnancy outcomes. The study population includes singleton pregnancies seen between 11 and 14 weeks at the Washington
1 Division of Maternal Fetal Medicine, Department of Obstetrics and Gynecology, Ultrasound and Genetic and Fetal Care Center, Washington University School of Medicine, St Louis, MO, USA and 2Department of Pathology and Immunology, Washington University School Of Medicine, St Louis, MO, USA. Correspondence: Dr AO Odibo, Division of Maternal Fetal Medicine, Washington University School of Medicine, 660S. Euclid Avenue, St Louis, MO 63110, USA. E-mail: [email protected] A poster presentation at the 33rd annual meeting of the Society of Maternal and Fetal Medicine, February, 2013, San Francisco, USA. Received 23 September 2013; revised 15 November 2013; accepted 4 December 2013; published online 16 January 2014
Placental pathology and first-trimester analytes AO Odibo et al
187 University Division of Ultrasound and Genetics as part of a screening program for aneuploidy. Cases with fetal or chromosomal anomalies or when placental slides could not be obtained for independent review were excluded. Fetal anomalies are defined as any major organ system malformation. The study was approved by the Institutional Review Board at Washington University in St Louis, MO, USA, and an informed consent was obtained from each of the participating patient. Details of the clinical diagnosis, maternal serum analyses and uterine artery evaluation have previously been described,19 but a brief overview will be provided below.
Clinical diagnosis Pre-eclampsia and other hypertensive disorders were defined using guidelines of the American College of Obstetricians and Gynecology20 and by the criteria proposed by the National High Blood Pressure Education Program Working Group Report in Pregnancy.21 Gestational hypertension (GH) was defined as elevated blood pressure (BP) without proteinuria detected for the first time in mid-pregnancy.21 Mild PE was defined as: BP 4140/90 mm Hg after 20 weeks gestation in a woman with a previously normal BP and proteinuria of X300 mg in a 24-h urine sample or at least 1 þ on urine dipstick. Severe PE was defined as the presence of any of the following in patients with PE: BP X160/110 mm Hg on X2 occasions at least 6 h apart; proteinuria of at least 5 g or 3 þ on urine dipstick on two samples randomly taken at least 4 h apart; elevated liver enzymes; visual disturbance, headache or other neurological disturbances; persistent right upper quadrant or epigastric pain; oliguria with o500 ml of urine in 24 h; oligohydramnios and fetal growth restriction. Small for gestational age (SGA) was defined as birth weight o10th percentile for GA using the growth chart by Alexander et al.22
Maternal serum analytes Approximately 10 cc of maternal blood was drawn by venipuncture into non-heparinized tubes. It was then allowed to clot and centrifuged at 1500 g for 15 min. The serum was removed, and aliquots were stored at 80 1C until further analysis. A serum sample of 25 ml from each patient was used to measure PP13 and ADAM12 concentrations by a time-resolved fluorescent immunoassay, where analyte concentration was directly proportional to the fluorescence measured on time-resolved fluorometer at 615 nm (DELFIA/AutoDELFIA research kit, PerkinElmer Life and Analytical Sciences, Turku, Finland). Duplicate measurements of each sample were obtained, and the test of repeatability performed for the assay revealed a mean intra-assay coefficient of variation of 6.8% and an inter-assay of 8.1%. Concentrations of PP13 were expressed as multiples of the median for GA and adjusted for maternal body mass index. PLGF levels were measured using enzymelinked immunoassay technique using the Quantikine immunoassay (R&D Systems Europe, Abington, UK). The lower limit of detection of the assay was 7 pg ml 1 for PLGF. The samples were analyzed by an examiner blinded to the clinical outcomes.
PAPP-A levels were measured by the PerkinElmer Laboratory as a part of routine first-trimester aneuploidy screening and also converted to multiples of the median. The PAPP-A levels were adjusted for maternal weight, ethnicity and smoking status and for pregnancies conceived using assisted reproductive technologies.
Uterine artery Doppler evaluation Doppler examination of the uterine arteries was performed using transabdominal ultrasound with color flow mapping. A mid-sagittal view of the uterus was obtained and the cervical canal identified. The transducer was then rotated until the paracervical vessels were visualized. The uterine artery was isolated and the pulsatility index (PI) was measured at this point. The mean PI of the measurements in each of the two uterine arteries was calculated. All participating sonographers are certified by the Nuchal Translucency Quality Review program (NTQR) for first-trimester screening.
Placental pathology Placental pathology was reviewed by two pathologists blinded to clinical outcomes. Placental findings were classified as: lesions of maternal under perfusion, including X1 of the following: infarct, decidual vasculopathy, distal villous hypoplasia Figures 1a–c; lesions causing reduced placental reserve, including perivillous fibrin/intervillous thrombosis-hematoma, or villitis (Figures 2a and b); infections/inflammatory lesions, including chorioamnionitis, funisitis or chorionic vasculitis (Figure 3a and b); and fetal vascular lesions, including avascular villi and occlusive or nonocclusive thrombi (Figure 4a and b). The control groups used for this comparison include pregnancies with no adverse outcomes and without the placental lesion being compared. For example, the control group for PE þ Lesions of maternal under perfusion will be pregnancies without PE, PTB and SGA and in which a lesion of maternal under perfusion was not present.
Statistical analyses Categorical and continuous variables were compared using chi-square, Student’s t-test and analysis of variance as appropriate. The distribution of the data was tested for normality using the Kolmogorov–Smirnov test. We first compared the levels of first-trimester biophysical markers (serum analytes and uterine artery Doppler PI) between cases with an adverse pregnancy outcome and those without the adverse outcome. We then compared the rates of various placental lesions in the pregnancies with adverse outcomes. Finally, we evaluated the association between firsttrimester markers and placental lesions seen in pregnancies with known adverse outcomes. All statistical analyses were performed using the STATA version 10.0 (Stata, College Station, TX, USA). Tests with P-valueso0.05 were considered significant.
Figure 1. Lesions of maternal under perfusion in the form of an infarct (a, 20), decidual vasculopathy or absent physiological transformation of blood vessels (b, 200) and distal villous hypoplasia (c, 200). & 2014 Nature America, Inc.
Journal of Perinatology (2014), 186 – 191
Placental pathology and first-trimester analytes AO Odibo et al
188
Figure 2.
Lesions of reduced placental reserve in the form of perivillous fibrin (a, 200) and necrotizing lymphohistiocytic villitis (b, 200).
Figure 3.
Other placental lesions of infection/inflammation-like severe acute chorioamnionitis (a, 200) and severe phlebitis (b, 200).
Figure 4.
Fetal vascular lesions in the form of avascular villi (a, 200) and complete occlusion of fetal vessel (c, 100).
RESULTS Over the study period, 301 patients were identified with placental histopathological evaluation at the time of delivery, of which slides were available for review for 193 patients and were assessed by two study pathologists KP and PH. The demographics of the study subjects are shown in Table 1. The majority of the subjects were African-American and the most common adverse pregnancy outcome was PTB ato37 weeks GA. The association between first-trimester biophysical markers and adverse pregnancy outcomes for the study cohort is shown in Table 2. Although most of the pregnancies with adverse outcomes had some significant association with abnormal first-trimester markers, GH had no significant association with the biophysical markers. Journal of Perinatology (2014), 186 – 191
Lesions of maternal under perfusion were seen in 50 cases (25.9%), lesions causing reduced placental reserve in 63 cases (32.85), infection/inflammation in 65 cases (34.2%) and fetal vascular lesions in 23 cases (11.9%). The association between placental pathology lesions and adverse pregnancy outcomes is shown in Table 3. Pregnancies with PE had significant association with lesions of maternal under perfusion (P ¼ 0.005) and decreased placental infection/inflammation (P ¼ 0.003). PTB ato28 weeks GA was the only sub-group of PTB with a significant association with infection/inflammation: 75% versus 31% (P ¼ 0.002). SGA and GH were not significantly associated with any histological abnormality. The results of the evaluation of association between pregnancies with adverse outcomes known to have specific placental lesions and first-trimester serum analytes are shown in Table 4. & 2014 Nature America, Inc.
Placental pathology and first-trimester analytes AO Odibo et al
189 Significant differences were seen in mean levels of PAPP-A, ADAM12 and PLGF in cases with PE, PTB and SGA with specific placental histological findings compared with controls. There were 123 pregnancies with no adverse pregnancy outcome or placental lesion available to be used as controls. The control groups for each comparison are different as the combination of cases with adverse pregnancy outcomes and the specific placental lesion changes depending on the prevalence of a placental lesion or other adverse outcomes. The most common finding was a significant difference between levels of PAPP-A in pregnancies with PE. Table 1. Demographics and background characteristics of study population
Maternal age (mean years, s.d.) Race White Black Asian Hispanic Others Smoking Gestational age at first-trimester screening (mean weeks, s.d.) Mean PAPP-A (MoM, s.d.) Mean ADAM12 (pg ml 1, s.d.) Mean PP13 (pg ml 1, s.d.) Mean PlGF (pg ml 1, s.d.) Mean uterine artery PI (s.d.) Pre-eclampsia Gestational hypertension Small for gestational age Preterm birth o37 weeks Gestational age at delivery (mean weeks, s.d.) Birth weight (mean g, s.d.)
N ¼ 193
%
29.5 (5.8)
—
77 86 22 4 4 16 12.1 (0.6)
39.9 44.5 11.4 2.1 2.1 8.4 —
1.2 (0.7) 485.1 (233.6) 59.1 (29.1) 21.0 (14.9) 1.7 (0.7) 36 19 29 48 36.9 (4.8)
— — — — — 18.6 9.8 15.0 24.9 —
2915 (928.4)
—
Abbreviations: ADAM12, a-disintegrin and metalloproteinase 12; MoM, multiples of the median; PAPP-A, pregnancy associated plasma protein A; PI, pulsatility index; PP13, placental protein 13; PLGF, placental growth factor.
Table 2.
Significant differences in the serum levels of ADAM12 and PlGF were seen in pregnancies, resulting in PTB in which lesions of maternal under perfusion and lesions causing reduced placental reserve were seen. SGA pregnancies with placental lesions suggestive of infection had significantly lower levels of PAPP-A, while those with fetal vascular lesions had lower levels of both PAPP-A and ADAM12.We found no significant difference in the levels of PP13 between any combination of adverse pregnancy outcome and placental histological finding when compared with the control groups. There were no significant differences in analytes between cases with GH and abnormal histology and the controls (data no shown). Uterine artery Doppler PI was not significantly different between the cases with adverse pregnancy outcomes and abnormal histology. DISCUSSION In this study, we found a significant association between firsttrimester serum markers and PE. We also found that those pregnancies with PE and lesions of maternal under perfusion on placental histology had significantly different levels of firsttrimester serum analytes when compared with a group that did not have this complication. In addition, those pregnancies complicated by PTB and specific placental histological findings had significant differences in the levels of first-trimester serum analytes compared with control groups. These placental pathological findings provide a biologically feasible link between abnormal levels of first-trimester serum analytes, PE, PTB and SGA. The findings from this study are consistent with those suggested by Costas et al.12 that reduced placental size and defective syncytiotrophoblast resulted in reduced secretion of PAPP-A, a known association with PE.. The lesions of maternal underperfusion, including infarction, decidual vasculopathy and distal villous hypoplasia, and lesions causing reduced placental reserve, such as perivillous fibrin or intervillous thrombus-hematoma or villitis, may be the pathological basis for this association. In addition, we found a significantly lower rate of placental infection or inflammation in the pregnancies with PE. This association should be explored in future studies. We also found no association between first-trimester uterine artery blood flow and PE, suggesting that this biophysical marker may not identify
Association between adverse pregnancy outcomes and first-trimester markers Mean uterine artery PI
PAPP-A (MoM)
ADAM12 (pg/ml)
PP13 (pg ml 1)
PLGF (pg ml 1)
Pre-eclampsia Yes: n ¼ 36 No: n ¼ 157
1.60 1.63
0.84* 1.27
438.0* 534.2
54.3 60.7
34.0* 44.8
Gestational hypertension Yes: n ¼ 19 No: n ¼ 174
1.56 1.64
1.31 1.92
473.0 523.1
59.8 59.6
35.1 42.0
APO
Preterm birth o37 weeks Yes: n ¼ 48 No: n ¼ 145 o28 weeks Yes: n ¼ 12 No: n ¼ 181
1.69 1.61
1.14 1.22
519.9 519.1
51.9* 62.5
31.2* 44.5
1.93* 1.61
1.17 1.20
452.3 523.8
52.5 60.2
31.9 40.8
Small for gestational age Yes: n ¼ 29 No: n ¼ 164
1.69 1.62
0.93* 1.24
459.5 524.2
60.4 59.7
35.6 41.1
Abbreviations: ADAM12, a-disintegrin and metalloproteinase 12; APO, adverse pregnancy outcomes (these are not mutually exclusive); PAPP-A, pregnancy associated plasma protein A; PI, pulsatility index; PLGF, placental growth factor; PP13, placental protein 13; MoM, multiples of the median. *Signifcant at Po0.05.
& 2014 Nature America, Inc.
Journal of Perinatology (2014), 186 – 191
Placental pathology and first-trimester analytes AO Odibo et al
190 Table 3.
Association between placental pathological lesions in pregnancies with adverse outcomes Lesions of maternal under perfusion (%)
P-value
Lesions causing reduced placental reserve (%)
P-value
Inflammation /infection (%)
P-value
Fetal vascular lesions (%)
P-value
18 (50.0) 41 (20.3)
0.005
13 (36.1) 37 (23.6)
0.12
4 (12.1) 61 (38.9)
0.003
7 (19.4) 16 (10.2)
0.12
Gestational hypertension Yes: n ¼ 19 5 (26.3) No: n ¼ 174 54 (31.2)
0.66
6 (31.6) 44 (25.3)
0.55
5 (26.3) 60 (35.1)
0.44
1 (5.3) 22 (12.6)
0.35
Preterm birth o37 weeks Yes: n ¼ 48 No: n ¼ 145 o28 weeks Yes: n ¼ 12 No: n ¼ 181
17 (35.4) 42 (29.2)
0.41
10 (20.8) 40 (27.6)
0.35
15 (32.6) 50 (34.7)
0.79
7 (14.6) 16 (11.0)
0.51
2 (16.7) 57 (31.7)
0.28
1 (8.3) 49 (27.1)
0.15
9 (75.0) 56 (31.5)
0.002
1 (8.3) 22 (12.2)
0.69
APO
Pre-eclampsia Yes: n ¼ 36 No: n ¼ 157
Small for gestational age Yes: n ¼ 29 10 (34.5) No: n ¼ 164 49 (29.9)
0.66
8 (26.7) 42 (26.1)
0.95
9 (31.0) 55 (33.5)
0.71
4 (13.3) 19 (11.8)
0.81
Abbreviation: APO, adverse pregnancy outcomes (these are not mutually exclusive).
Table 4.
Adverse pregnancy outcomes, placental histological findings and first-trimester markers
APO þ placental pathology (n) PE þ lesions of maternal under perfusion (18) Control (115) PE þ lesions causing reduced placental reserve (13) Control (123) PE þ infection (4) Control (96) PE þ fetal vascular lesions (7) Control (84) PTB þ lesions of maternal under perfusion (17) Control (102) PTB þ lesions causing reduced placental reserve (10) Control (109) PTB þ infection (15) Control (94) PTB þ fetal vascular lesions (7) Control (84) SGA þ lesions of maternal under perfusion (10) Control (108) SGA þ lesions causing reduced placental reserve (8) Control (101) SGA þ infection (9) Control (107) SGA þ fetal vascular lesions (4) Control (88)
PAPP-A (MoM), mean±s.d.
ADAM12 (pg ml 1), mean±s.d.
PP13 (pg ml 1), mean±s.d.
PLGF (pg ml 1), mean±s.d.
0.8±0.4* 1.2±0.8 0.8±0.5* 1.2±0.7 0.7±0.1* 1.2 ±0.7 0.8±0.5z 1.3±0.7 1.0±0.8 1.2±0.7 1.2±0.8 1.2±0.6 1.1±1.0 1.1±0.7 1.1±0.6 1.3±0.7 1.0±0.9 1.2±0.7 1.0±0.8 1.2±0.7 0.8±0.3* 1.2±0.7 0.7±0.3* 1.3±0.7
529±282 514±257 365±180* 488±230 473±240 502±234 431±271 539±239 415±217 510±260 381±170* 509±238 380±199 503±244 497±253 540±239 462±164 531±255 452±199 531±253 398±166 536±252 333±175* 540±239
60±32.3 59±51 54±37 59±27 88±30 59±26 70±58 61±25 44±22 59±29 45±36 62±27 50±20 59±26 75±52 61±25 66±31 62±23 64±38 62±27 78±27 62±27 NA
15±8* 22±15 21±11 23±16 20±5 19±16 23±15 21±17 16±9* 22±15 18±12 23±17 24±15 20±16 15±11 21±17 8±25 21±16 22±12 22±17 27±24 21±16 20±14 21±17
Abbreviations: ADAM12, a-disintegrin and metalloproteinase 12; APO, adverse pregnancy outcome; MoM, multiples of the median; NA, samples not available in cases for comparison; PAPP-A, pregnancy associated plasma protein A; PE, pre-eclampsia; PI, pulsatility index; PLGF, placental growth factor; PP13, placental protein 13; PTB, preterm birth; SGA, small for gestational age. Control are those with no adverse pregnancy outcome. *Signifcant at Po0.05 calculated by paired t-test. zP ¼ 0.06.
pregnancies with lesions of maternal under perfusion this early in pregnancy. The finding that only those PTBs occurring before 28 weeks were associated with infection or inflammation is consistent with previous reports that chorio-amnionitis appears to be more common the earlier the GA of PTB.23 Pregnancies resulting in PTB and having lesions of maternal under perfusion and lesions causing reduced placental reserve were associated with reduced levels of serum analytes (Table 4). The significant analytes in these Journal of Perinatology (2014), 186 – 191
cases with PTB were ADAM12 and PlGF. PP13 was only associated with PTB when defined as deliveries occurring before 37 weeks and was not significantly associated with any of the placental pathological lesions. The study is not without limitations, including the small sample size and the low prevalence of some placental lesions such as fetal vascular lesions, and in the subgroup analyses, some cases with adverse outcomes such as SGA did not have levels of PP13 to be compared with the control group. The latter was because the & 2014 Nature America, Inc.
Placental pathology and first-trimester analytes AO Odibo et al
191 company manufacturing the kits for PP13 stopped producing them towards the end of the study period as we have previously reported.24 In addition, because some of the patients delivered at outside hospitals, we were unable to obtain their slides for independent review by the study pathologists. In conclusion, we found a significant association between abnormal levels of first-trimester serum markers and certain pathological lesions seen in PE, SGA and PTB. Although these associations were not consistent among all serum markers evaluated, our study provides the link associating these placental lesions with suboptimal secretion of these serum markers in pregnancies with adverse outcomes.
11
12
13
14
CONFLICT OF INTEREST The authors declare no conflict of interest. 15
REFERENCES 1 Cowans NJ, Stamatopoulou A, Khalil A, Spencer K. PP13 as a marker of preeclampsia: a two platform comparison study. Placenta 2011; 32(Suppl): S37–S41. 2 Wortelboer EJ, Koster MP, Cuckle HS, Stoutenbeek PH, Schielen PC, Visser GH. First-trimester placental protein 13 and placental growth factor: markers for identification of women destined to develop early-onset pre-eclampsia. BJOG 2010; 117(11): 1384–1389. 3 Romero R, Kusanovic JP, Than NG, Erez O, Gotsch F, Espinoza J et al. First-trimester maternal serum PP13 in the risk assessment for preeclampsia. Am J Obstet Gynecol 2008; 199: 122e1–122e11. 4 Chafetz I, Kuhnreich I, Sammar M, Tal Y, Gibor Y, Meiri H et al. First-trimester placental protein 13 screening for preeclampsia and intrauterine growth restriction. Am J Obstet Gynecol 2007; 197(35): e1–e7. 5 Spencer K, Cowans NJ, Chefetz I, Tal J, Meiri H. First-trimester maternal serum PP-13, PAPP-A and second-trimester uterine artery Doppler pulsatility index as markers of pre-eclampsia. Ultrasound Obstet Gynecol 2007; 29: 128–134. 6 Spencer K, Cowans NJ, Nicolaides KH. Low levels of maternal serum PAPP-A in the first trimester and the risk of pre-eclampsia. Prenat Diagn 2008; 28: 7–10. 7 Sekizawa A, Purwosunu Y, Yoshimura S, Nakamura M, Shimizu H, Okai T et al. PP13 mRNA expression in trophoblasts from preeclamptic placentas. Reprod Sci 2009; 16: 408–413. 8 Goetzinger KR, Cahill AG, Kemna J, Odibo L, Macones GA, Odibo AO. Firsttrimester prediction of preterm birth using ADAM12, PAPP-A, uterine artery Doppler, and maternal characteristics. Prenat Diagn 2012; 32(10): 1002–1007. 9 Akolekar R, Zaragoza E, Poon LC, Pepes S, Nicolaides KH. Maternal serum placental growth factor at 11 þ 0 to 13 þ 6 weeks of gestation in the prediction of pre-eclampsia. Ultrasound Obstet Gynecol 2008; 32: 732–739. 10 Crispi F, Llurba E, Dominguez C, Martin-Gallan P, Cabero L, Gratacos E. Predictive value of angiogenic factors and uterine artery Doppler for early- versus late-onset
& 2014 Nature America, Inc.
16
17
18
19
20
21
22 23
24
pre-eclampsia and intrauterine growth restriction. Ultrasound Obstet Gynecol 2008; 31: 303–309. Goetzinger KR, Zhong Y, Cahill AG, Odibo L, Macones GA, Odibo AO. Efficiency of first-trimester uterine artery Doppler, a-disintegrin and metalloprotease 12, pregnancy-associated plasma protein A, and maternal characteristics in the prediction of preeclampsia. J Ultrasound Med 2013; 32: 1593–1600. Costa SL, Proctor L, Dodd JM, Toal M, Okun N, Johnson JA et al. Screening for placental insufficiency in high-risk pregnancies: is earlier better? Placenta 2008; 29: 1034–1040. Cindrova-Davies T, Spasic-Boskovic O, Jauniaux E, Charnock-Jones DS, Burton GJ. Nuclear factor-kappa B, p38, and stress-activated protein kinase mitogen-activated protein kinase signaling pathways regulate proinflammatory cytokines and apoptosis in human placental explants in response to oxidative stress: effects of antioxidant vitamins. Am J Pathol 2007; 170: 1511–1520. Hung TH, Charnock-Jones DS, Skepper JN, Burton GJ. Secretion of tumor necrosis factor-alpha from human placental tissues induced by hypoxia-reoxygenation causes endothelial cell activation in vitro: a potential mediator of the inflammatory response in preeclampsia. Am J Pathol 2004; 164: 1049–1061. Tjoa ML, Cindrova-Davies T, Spasic-Boskovic O, Bianchi DW, Burton GJ. Trophoblastic oxidative stress and the release of cell-free feto-placental DNA. Am J Pathol 2006; 169: 400–404. Moldenhauer JS, Stanek J, Warshak C, Khoury J, SIBAI B. The frequency and severity of placental findings in women with preeclampsia are gestational age dependent. Am J Obstet Gynecol 2003; 189: 1173–1177. Egbor M, Ansari T, Morris N, Green CJ, Sibbons PD. Morphometric placental villous and vascular abnormalities in early- and late-onset pre-eclampsia with and without fetal growth restriction. BJOG 2006; 113: 580–589. Melchiorre K, Wormald B, Leslie K, Bhide A, Thilaganathan B. First-trimester uterine artery Doppler indices in term and preterm pre-eclampsia. Ultrasound Obstet Gynecol 2008; 32: 133–137. Odibo AO, Zhong Y, Longtine M, Tuuli M, Odibo L, Cahill AG et al. First-trimester serum analytes, biophysical tests and the association with pathological morphometry in the placenta of pregnancies with preeclampsia and fetal growth restriction. Placenta 2011; 32(4): 333–338. American College of Obstetricians and Gynecologists. Diagnosis and Management of Preeclampsia and Eclampsia. ACOG Practice Bulletin No. 33. ACOG: Washington, DC, USA, 2002. Report of the National High Blood Pressure Education Program Working Group. Report on high blood pressure in pregnancy. Am J Obstet Gynecol 2000; 183: S1–S22. Alexander GR, Himes JH, Kaufman RB, Mor J, Kogan MA. United States national reference for fetal growth. Obstet Gynecol 1996; 87: 163–168. Tsiartas P, Kacerovsky M, Musilova I, Hornychova H, Cobo T, Sa¨vman K et al. The association between histological chorioamnionitis, funisitis and neonatal outcome in women with preterm prelabor rupture of membranes. J Matern Fetal Neonatal Med 2013; 26: 1332–1336. Odibo AO, Zhong Y, Goetzinger KR, Odibo L, Bick JL, Bower CR et al. First-trimester placental protein 13, PAPP-A, uterine artery Doppler and maternal characteristics in the prediction of pre-eclampsia. Placenta 2011; 32(8): 598–602.
Journal of Perinatology (2014), 186 – 191
ORIGINAL ARTICLE
Placental pathology, first-trimester biomarkers and adverse pregnancy outcomes AO Odibo1, KR Patel2, A Spitalnik1, L Odibo1 and P Huettner2 OBJECTIVE: We investigated the relationship between placental pathological findings in pregnancies with adverse pregnancy outcomes and first-trimester serum analytes and uterine artery Doppler results. STUDY DESIGN: This is a secondary analysis of a prospective study of first-trimester screening for adverse pregnancy outcomes, including preterm birth (PTB (deliveryo37 weeks)), pre-eclampsia (PE), gestational hypertension, and small for gestational age (SGA) infants (birth weight o10th percentile). We compared the mean levels of serum analytes (pregnancy-associated plasma protein A (PAPP-A), placental protein 13 (PP13), a-disintegrin and metalloproteinase 12 (ADAM12), placental growth factor (PLGF)) and uterine artery Doppler pulsatility index (UADPI) obtained between 11 and 14 weeks gestation in cases with adverse outcomes and abnormal placental histology to a control group without adverse outcome or abnormal placental pathology. Placental findings were classified as: lesions of maternal under perfusion, lesions causing reduced placental reserve, infections/inflammatory lesions, and fetal vascular lesions. RESULT: Among 193 cases, lesions of maternal under perfusion were seen in 50 cases (25.9%), lesions causing reduced placental reserve in 63 cases (32.8%), infection/inflammation in 65 cases (34.2%) and fetal vascular lesions in 23 cases (11.9%). There were 123 pregnancies with no adverse pregnancy outcome or placental lesion used as controls. Pregnancies with PE had a significant association with lesions of maternal under perfusion (P ¼ 0.005) and placental infection/inflammation (P ¼ 0.003). Significant differences were seen in mean levels of PAPP-A, ADAM12 and PLGF in cases with PE, PTB and SGA with specific placental histological findings when compared with controls. UADPI was not significantly different between the cases with adverse pregnancy outcomes and abnormal histology. CONCLUSION: Our findings provide evidence linking placental pathology with suboptimal secretion of analytes in the first trimester in pregnancies with adverse outcomes, especially PE. Journal of Perinatology (2014) 34, 186–191; doi:10.1038/jp.2013.176; published online 16 January 2014 Keywords: placental pathology; first-trimester; serum analytes; adverse pregnancy outcomes
INTRODUCTION Recent reports suggest the potential role of placental proteins, including placental protein 13 (PP13) and pregnancy-associated plasma protein A (PAPP-A), in identifying pregnancies at risk for later development of pre-eclampsia (PE) and preterm birth (PTB).1–8 PPP13 is a member of the galectin family produced by the syncytiotrophoblast3 and is thought to be involved in placental implantation and vascular remodeling.4 Reduced levels of PP13 mRNA levels have been reported in the placentas of women who developed preterm PE.7 In addition, numerous studies have documented that placental growth factor (PLGF) concentration in the first trimester is reduced in women who go on to develop PE and fetal growth restriction.9–10 In addition, our group in previous studies has shown an association between low levels of a-disintegrin and metalloproteinase 12 (ADAM12) in pregnancies with PE and PTB.8,11 Although the exact mechanisms resulting in abnormal secretion of these placental proteins are not clearly understood, some biologically feasible explanations have been proposed. These include reduced placental size or defective syncytiotrophoblast formation resulting in reduced production of placenta-derived proteins, such as PAPP-A12; and hypoxia-reoxygenation induced increased secretion of pro-inflammatory cytokines, such as tumor
necrosis factor a and interleukin-1b, and anti-angiogenic factors, such as the soluble receptor for vascular endothelial growth factor 1.13–15 Placental pathological studies indicate that PE or fetal growth restriction resulting in preterm delivery before 34 weeks have high rates of thrombotic placental pathological findings of the villous trees.16 In contrast, the placentas from term pregnancies with PE and/or fetal growth restriction demonstrate either normal or minimal pathological findings.17 Doppler studies also suggest that preterm PE and fetal growth restriction are associated with defective invasion of the spiral arteries, whereas the spiral artery defect has a much smaller role in cases nearer term.18 The aim of this study is to investigate the hypothesis that the relationship between adverse pregnancy outcomes (APO) and first-trimester serum analytes and uterine artery Doppler results are secondary to underlying specific placental lesions.
METHODS This is a secondary analysis of a prospective study of first-trimester screening for adverse pregnancy outcomes. The study population includes singleton pregnancies seen between 11 and 14 weeks at the Washington
1 Division of Maternal Fetal Medicine, Department of Obstetrics and Gynecology, Ultrasound and Genetic and Fetal Care Center, Washington University School of Medicine, St Louis, MO, USA and 2Department of Pathology and Immunology, Washington University School Of Medicine, St Louis, MO, USA. Correspondence: Dr AO Odibo, Division of Maternal Fetal Medicine, Washington University School of Medicine, 660S. Euclid Avenue, St Louis, MO 63110, USA. E-mail: [email protected] A poster presentation at the 33rd annual meeting of the Society of Maternal and Fetal Medicine, February, 2013, San Francisco, USA. Received 23 September 2013; revised 15 November 2013; accepted 4 December 2013; published online 16 January 2014
Placental pathology and first-trimester analytes AO Odibo et al
187 University Division of Ultrasound and Genetics as part of a screening program for aneuploidy. Cases with fetal or chromosomal anomalies or when placental slides could not be obtained for independent review were excluded. Fetal anomalies are defined as any major organ system malformation. The study was approved by the Institutional Review Board at Washington University in St Louis, MO, USA, and an informed consent was obtained from each of the participating patient. Details of the clinical diagnosis, maternal serum analyses and uterine artery evaluation have previously been described,19 but a brief overview will be provided below.
Clinical diagnosis Pre-eclampsia and other hypertensive disorders were defined using guidelines of the American College of Obstetricians and Gynecology20 and by the criteria proposed by the National High Blood Pressure Education Program Working Group Report in Pregnancy.21 Gestational hypertension (GH) was defined as elevated blood pressure (BP) without proteinuria detected for the first time in mid-pregnancy.21 Mild PE was defined as: BP 4140/90 mm Hg after 20 weeks gestation in a woman with a previously normal BP and proteinuria of X300 mg in a 24-h urine sample or at least 1 þ on urine dipstick. Severe PE was defined as the presence of any of the following in patients with PE: BP X160/110 mm Hg on X2 occasions at least 6 h apart; proteinuria of at least 5 g or 3 þ on urine dipstick on two samples randomly taken at least 4 h apart; elevated liver enzymes; visual disturbance, headache or other neurological disturbances; persistent right upper quadrant or epigastric pain; oliguria with o500 ml of urine in 24 h; oligohydramnios and fetal growth restriction. Small for gestational age (SGA) was defined as birth weight o10th percentile for GA using the growth chart by Alexander et al.22
Maternal serum analytes Approximately 10 cc of maternal blood was drawn by venipuncture into non-heparinized tubes. It was then allowed to clot and centrifuged at 1500 g for 15 min. The serum was removed, and aliquots were stored at 80 1C until further analysis. A serum sample of 25 ml from each patient was used to measure PP13 and ADAM12 concentrations by a time-resolved fluorescent immunoassay, where analyte concentration was directly proportional to the fluorescence measured on time-resolved fluorometer at 615 nm (DELFIA/AutoDELFIA research kit, PerkinElmer Life and Analytical Sciences, Turku, Finland). Duplicate measurements of each sample were obtained, and the test of repeatability performed for the assay revealed a mean intra-assay coefficient of variation of 6.8% and an inter-assay of 8.1%. Concentrations of PP13 were expressed as multiples of the median for GA and adjusted for maternal body mass index. PLGF levels were measured using enzymelinked immunoassay technique using the Quantikine immunoassay (R&D Systems Europe, Abington, UK). The lower limit of detection of the assay was 7 pg ml 1 for PLGF. The samples were analyzed by an examiner blinded to the clinical outcomes.
PAPP-A levels were measured by the PerkinElmer Laboratory as a part of routine first-trimester aneuploidy screening and also converted to multiples of the median. The PAPP-A levels were adjusted for maternal weight, ethnicity and smoking status and for pregnancies conceived using assisted reproductive technologies.
Uterine artery Doppler evaluation Doppler examination of the uterine arteries was performed using transabdominal ultrasound with color flow mapping. A mid-sagittal view of the uterus was obtained and the cervical canal identified. The transducer was then rotated until the paracervical vessels were visualized. The uterine artery was isolated and the pulsatility index (PI) was measured at this point. The mean PI of the measurements in each of the two uterine arteries was calculated. All participating sonographers are certified by the Nuchal Translucency Quality Review program (NTQR) for first-trimester screening.
Placental pathology Placental pathology was reviewed by two pathologists blinded to clinical outcomes. Placental findings were classified as: lesions of maternal under perfusion, including X1 of the following: infarct, decidual vasculopathy, distal villous hypoplasia Figures 1a–c; lesions causing reduced placental reserve, including perivillous fibrin/intervillous thrombosis-hematoma, or villitis (Figures 2a and b); infections/inflammatory lesions, including chorioamnionitis, funisitis or chorionic vasculitis (Figure 3a and b); and fetal vascular lesions, including avascular villi and occlusive or nonocclusive thrombi (Figure 4a and b). The control groups used for this comparison include pregnancies with no adverse outcomes and without the placental lesion being compared. For example, the control group for PE þ Lesions of maternal under perfusion will be pregnancies without PE, PTB and SGA and in which a lesion of maternal under perfusion was not present.
Statistical analyses Categorical and continuous variables were compared using chi-square, Student’s t-test and analysis of variance as appropriate. The distribution of the data was tested for normality using the Kolmogorov–Smirnov test. We first compared the levels of first-trimester biophysical markers (serum analytes and uterine artery Doppler PI) between cases with an adverse pregnancy outcome and those without the adverse outcome. We then compared the rates of various placental lesions in the pregnancies with adverse outcomes. Finally, we evaluated the association between firsttrimester markers and placental lesions seen in pregnancies with known adverse outcomes. All statistical analyses were performed using the STATA version 10.0 (Stata, College Station, TX, USA). Tests with P-valueso0.05 were considered significant.
Figure 1. Lesions of maternal under perfusion in the form of an infarct (a, 20), decidual vasculopathy or absent physiological transformation of blood vessels (b, 200) and distal villous hypoplasia (c, 200). & 2014 Nature America, Inc.
Journal of Perinatology (2014), 186 – 191
Placental pathology and first-trimester analytes AO Odibo et al
188
Figure 2.
Lesions of reduced placental reserve in the form of perivillous fibrin (a, 200) and necrotizing lymphohistiocytic villitis (b, 200).
Figure 3.
Other placental lesions of infection/inflammation-like severe acute chorioamnionitis (a, 200) and severe phlebitis (b, 200).
Figure 4.
Fetal vascular lesions in the form of avascular villi (a, 200) and complete occlusion of fetal vessel (c, 100).
RESULTS Over the study period, 301 patients were identified with placental histopathological evaluation at the time of delivery, of which slides were available for review for 193 patients and were assessed by two study pathologists KP and PH. The demographics of the study subjects are shown in Table 1. The majority of the subjects were African-American and the most common adverse pregnancy outcome was PTB ato37 weeks GA. The association between first-trimester biophysical markers and adverse pregnancy outcomes for the study cohort is shown in Table 2. Although most of the pregnancies with adverse outcomes had some significant association with abnormal first-trimester markers, GH had no significant association with the biophysical markers. Journal of Perinatology (2014), 186 – 191
Lesions of maternal under perfusion were seen in 50 cases (25.9%), lesions causing reduced placental reserve in 63 cases (32.85), infection/inflammation in 65 cases (34.2%) and fetal vascular lesions in 23 cases (11.9%). The association between placental pathology lesions and adverse pregnancy outcomes is shown in Table 3. Pregnancies with PE had significant association with lesions of maternal under perfusion (P ¼ 0.005) and decreased placental infection/inflammation (P ¼ 0.003). PTB ato28 weeks GA was the only sub-group of PTB with a significant association with infection/inflammation: 75% versus 31% (P ¼ 0.002). SGA and GH were not significantly associated with any histological abnormality. The results of the evaluation of association between pregnancies with adverse outcomes known to have specific placental lesions and first-trimester serum analytes are shown in Table 4. & 2014 Nature America, Inc.
Placental pathology and first-trimester analytes AO Odibo et al
189 Significant differences were seen in mean levels of PAPP-A, ADAM12 and PLGF in cases with PE, PTB and SGA with specific placental histological findings compared with controls. There were 123 pregnancies with no adverse pregnancy outcome or placental lesion available to be used as controls. The control groups for each comparison are different as the combination of cases with adverse pregnancy outcomes and the specific placental lesion changes depending on the prevalence of a placental lesion or other adverse outcomes. The most common finding was a significant difference between levels of PAPP-A in pregnancies with PE. Table 1. Demographics and background characteristics of study population
Maternal age (mean years, s.d.) Race White Black Asian Hispanic Others Smoking Gestational age at first-trimester screening (mean weeks, s.d.) Mean PAPP-A (MoM, s.d.) Mean ADAM12 (pg ml 1, s.d.) Mean PP13 (pg ml 1, s.d.) Mean PlGF (pg ml 1, s.d.) Mean uterine artery PI (s.d.) Pre-eclampsia Gestational hypertension Small for gestational age Preterm birth o37 weeks Gestational age at delivery (mean weeks, s.d.) Birth weight (mean g, s.d.)
N ¼ 193
%
29.5 (5.8)
—
77 86 22 4 4 16 12.1 (0.6)
39.9 44.5 11.4 2.1 2.1 8.4 —
1.2 (0.7) 485.1 (233.6) 59.1 (29.1) 21.0 (14.9) 1.7 (0.7) 36 19 29 48 36.9 (4.8)
— — — — — 18.6 9.8 15.0 24.9 —
2915 (928.4)
—
Abbreviations: ADAM12, a-disintegrin and metalloproteinase 12; MoM, multiples of the median; PAPP-A, pregnancy associated plasma protein A; PI, pulsatility index; PP13, placental protein 13; PLGF, placental growth factor.
Table 2.
Significant differences in the serum levels of ADAM12 and PlGF were seen in pregnancies, resulting in PTB in which lesions of maternal under perfusion and lesions causing reduced placental reserve were seen. SGA pregnancies with placental lesions suggestive of infection had significantly lower levels of PAPP-A, while those with fetal vascular lesions had lower levels of both PAPP-A and ADAM12.We found no significant difference in the levels of PP13 between any combination of adverse pregnancy outcome and placental histological finding when compared with the control groups. There were no significant differences in analytes between cases with GH and abnormal histology and the controls (data no shown). Uterine artery Doppler PI was not significantly different between the cases with adverse pregnancy outcomes and abnormal histology. DISCUSSION In this study, we found a significant association between firsttrimester serum markers and PE. We also found that those pregnancies with PE and lesions of maternal under perfusion on placental histology had significantly different levels of firsttrimester serum analytes when compared with a group that did not have this complication. In addition, those pregnancies complicated by PTB and specific placental histological findings had significant differences in the levels of first-trimester serum analytes compared with control groups. These placental pathological findings provide a biologically feasible link between abnormal levels of first-trimester serum analytes, PE, PTB and SGA. The findings from this study are consistent with those suggested by Costas et al.12 that reduced placental size and defective syncytiotrophoblast resulted in reduced secretion of PAPP-A, a known association with PE.. The lesions of maternal underperfusion, including infarction, decidual vasculopathy and distal villous hypoplasia, and lesions causing reduced placental reserve, such as perivillous fibrin or intervillous thrombus-hematoma or villitis, may be the pathological basis for this association. In addition, we found a significantly lower rate of placental infection or inflammation in the pregnancies with PE. This association should be explored in future studies. We also found no association between first-trimester uterine artery blood flow and PE, suggesting that this biophysical marker may not identify
Association between adverse pregnancy outcomes and first-trimester markers Mean uterine artery PI
PAPP-A (MoM)
ADAM12 (pg/ml)
PP13 (pg ml 1)
PLGF (pg ml 1)
Pre-eclampsia Yes: n ¼ 36 No: n ¼ 157
1.60 1.63
0.84* 1.27
438.0* 534.2
54.3 60.7
34.0* 44.8
Gestational hypertension Yes: n ¼ 19 No: n ¼ 174
1.56 1.64
1.31 1.92
473.0 523.1
59.8 59.6
35.1 42.0
APO
Preterm birth o37 weeks Yes: n ¼ 48 No: n ¼ 145 o28 weeks Yes: n ¼ 12 No: n ¼ 181
1.69 1.61
1.14 1.22
519.9 519.1
51.9* 62.5
31.2* 44.5
1.93* 1.61
1.17 1.20
452.3 523.8
52.5 60.2
31.9 40.8
Small for gestational age Yes: n ¼ 29 No: n ¼ 164
1.69 1.62
0.93* 1.24
459.5 524.2
60.4 59.7
35.6 41.1
Abbreviations: ADAM12, a-disintegrin and metalloproteinase 12; APO, adverse pregnancy outcomes (these are not mutually exclusive); PAPP-A, pregnancy associated plasma protein A; PI, pulsatility index; PLGF, placental growth factor; PP13, placental protein 13; MoM, multiples of the median. *Signifcant at Po0.05.
& 2014 Nature America, Inc.
Journal of Perinatology (2014), 186 – 191
Placental pathology and first-trimester analytes AO Odibo et al
190 Table 3.
Association between placental pathological lesions in pregnancies with adverse outcomes Lesions of maternal under perfusion (%)
P-value
Lesions causing reduced placental reserve (%)
P-value
Inflammation /infection (%)
P-value
Fetal vascular lesions (%)
P-value
18 (50.0) 41 (20.3)
0.005
13 (36.1) 37 (23.6)
0.12
4 (12.1) 61 (38.9)
0.003
7 (19.4) 16 (10.2)
0.12
Gestational hypertension Yes: n ¼ 19 5 (26.3) No: n ¼ 174 54 (31.2)
0.66
6 (31.6) 44 (25.3)
0.55
5 (26.3) 60 (35.1)
0.44
1 (5.3) 22 (12.6)
0.35
Preterm birth o37 weeks Yes: n ¼ 48 No: n ¼ 145 o28 weeks Yes: n ¼ 12 No: n ¼ 181
17 (35.4) 42 (29.2)
0.41
10 (20.8) 40 (27.6)
0.35
15 (32.6) 50 (34.7)
0.79
7 (14.6) 16 (11.0)
0.51
2 (16.7) 57 (31.7)
0.28
1 (8.3) 49 (27.1)
0.15
9 (75.0) 56 (31.5)
0.002
1 (8.3) 22 (12.2)
0.69
APO
Pre-eclampsia Yes: n ¼ 36 No: n ¼ 157
Small for gestational age Yes: n ¼ 29 10 (34.5) No: n ¼ 164 49 (29.9)
0.66
8 (26.7) 42 (26.1)
0.95
9 (31.0) 55 (33.5)
0.71
4 (13.3) 19 (11.8)
0.81
Abbreviation: APO, adverse pregnancy outcomes (these are not mutually exclusive).
Table 4.
Adverse pregnancy outcomes, placental histological findings and first-trimester markers
APO þ placental pathology (n) PE þ lesions of maternal under perfusion (18) Control (115) PE þ lesions causing reduced placental reserve (13) Control (123) PE þ infection (4) Control (96) PE þ fetal vascular lesions (7) Control (84) PTB þ lesions of maternal under perfusion (17) Control (102) PTB þ lesions causing reduced placental reserve (10) Control (109) PTB þ infection (15) Control (94) PTB þ fetal vascular lesions (7) Control (84) SGA þ lesions of maternal under perfusion (10) Control (108) SGA þ lesions causing reduced placental reserve (8) Control (101) SGA þ infection (9) Control (107) SGA þ fetal vascular lesions (4) Control (88)
PAPP-A (MoM), mean±s.d.
ADAM12 (pg ml 1), mean±s.d.
PP13 (pg ml 1), mean±s.d.
PLGF (pg ml 1), mean±s.d.
0.8±0.4* 1.2±0.8 0.8±0.5* 1.2±0.7 0.7±0.1* 1.2 ±0.7 0.8±0.5z 1.3±0.7 1.0±0.8 1.2±0.7 1.2±0.8 1.2±0.6 1.1±1.0 1.1±0.7 1.1±0.6 1.3±0.7 1.0±0.9 1.2±0.7 1.0±0.8 1.2±0.7 0.8±0.3* 1.2±0.7 0.7±0.3* 1.3±0.7
529±282 514±257 365±180* 488±230 473±240 502±234 431±271 539±239 415±217 510±260 381±170* 509±238 380±199 503±244 497±253 540±239 462±164 531±255 452±199 531±253 398±166 536±252 333±175* 540±239
60±32.3 59±51 54±37 59±27 88±30 59±26 70±58 61±25 44±22 59±29 45±36 62±27 50±20 59±26 75±52 61±25 66±31 62±23 64±38 62±27 78±27 62±27 NA
15±8* 22±15 21±11 23±16 20±5 19±16 23±15 21±17 16±9* 22±15 18±12 23±17 24±15 20±16 15±11 21±17 8±25 21±16 22±12 22±17 27±24 21±16 20±14 21±17
Abbreviations: ADAM12, a-disintegrin and metalloproteinase 12; APO, adverse pregnancy outcome; MoM, multiples of the median; NA, samples not available in cases for comparison; PAPP-A, pregnancy associated plasma protein A; PE, pre-eclampsia; PI, pulsatility index; PLGF, placental growth factor; PP13, placental protein 13; PTB, preterm birth; SGA, small for gestational age. Control are those with no adverse pregnancy outcome. *Signifcant at Po0.05 calculated by paired t-test. zP ¼ 0.06.
pregnancies with lesions of maternal under perfusion this early in pregnancy. The finding that only those PTBs occurring before 28 weeks were associated with infection or inflammation is consistent with previous reports that chorio-amnionitis appears to be more common the earlier the GA of PTB.23 Pregnancies resulting in PTB and having lesions of maternal under perfusion and lesions causing reduced placental reserve were associated with reduced levels of serum analytes (Table 4). The significant analytes in these Journal of Perinatology (2014), 186 – 191
cases with PTB were ADAM12 and PlGF. PP13 was only associated with PTB when defined as deliveries occurring before 37 weeks and was not significantly associated with any of the placental pathological lesions. The study is not without limitations, including the small sample size and the low prevalence of some placental lesions such as fetal vascular lesions, and in the subgroup analyses, some cases with adverse outcomes such as SGA did not have levels of PP13 to be compared with the control group. The latter was because the & 2014 Nature America, Inc.
Placental pathology and first-trimester analytes AO Odibo et al
191 company manufacturing the kits for PP13 stopped producing them towards the end of the study period as we have previously reported.24 In addition, because some of the patients delivered at outside hospitals, we were unable to obtain their slides for independent review by the study pathologists. In conclusion, we found a significant association between abnormal levels of first-trimester serum markers and certain pathological lesions seen in PE, SGA and PTB. Although these associations were not consistent among all serum markers evaluated, our study provides the link associating these placental lesions with suboptimal secretion of these serum markers in pregnancies with adverse outcomes.
11
12
13
14
CONFLICT OF INTEREST The authors declare no conflict of interest. 15
REFERENCES 1 Cowans NJ, Stamatopoulou A, Khalil A, Spencer K. PP13 as a marker of preeclampsia: a two platform comparison study. Placenta 2011; 32(Suppl): S37–S41. 2 Wortelboer EJ, Koster MP, Cuckle HS, Stoutenbeek PH, Schielen PC, Visser GH. First-trimester placental protein 13 and placental growth factor: markers for identification of women destined to develop early-onset pre-eclampsia. BJOG 2010; 117(11): 1384–1389. 3 Romero R, Kusanovic JP, Than NG, Erez O, Gotsch F, Espinoza J et al. First-trimester maternal serum PP13 in the risk assessment for preeclampsia. Am J Obstet Gynecol 2008; 199: 122e1–122e11. 4 Chafetz I, Kuhnreich I, Sammar M, Tal Y, Gibor Y, Meiri H et al. First-trimester placental protein 13 screening for preeclampsia and intrauterine growth restriction. Am J Obstet Gynecol 2007; 197(35): e1–e7. 5 Spencer K, Cowans NJ, Chefetz I, Tal J, Meiri H. First-trimester maternal serum PP-13, PAPP-A and second-trimester uterine artery Doppler pulsatility index as markers of pre-eclampsia. Ultrasound Obstet Gynecol 2007; 29: 128–134. 6 Spencer K, Cowans NJ, Nicolaides KH. Low levels of maternal serum PAPP-A in the first trimester and the risk of pre-eclampsia. Prenat Diagn 2008; 28: 7–10. 7 Sekizawa A, Purwosunu Y, Yoshimura S, Nakamura M, Shimizu H, Okai T et al. PP13 mRNA expression in trophoblasts from preeclamptic placentas. Reprod Sci 2009; 16: 408–413. 8 Goetzinger KR, Cahill AG, Kemna J, Odibo L, Macones GA, Odibo AO. Firsttrimester prediction of preterm birth using ADAM12, PAPP-A, uterine artery Doppler, and maternal characteristics. Prenat Diagn 2012; 32(10): 1002–1007. 9 Akolekar R, Zaragoza E, Poon LC, Pepes S, Nicolaides KH. Maternal serum placental growth factor at 11 þ 0 to 13 þ 6 weeks of gestation in the prediction of pre-eclampsia. Ultrasound Obstet Gynecol 2008; 32: 732–739. 10 Crispi F, Llurba E, Dominguez C, Martin-Gallan P, Cabero L, Gratacos E. Predictive value of angiogenic factors and uterine artery Doppler for early- versus late-onset
& 2014 Nature America, Inc.
16
17
18
19
20
21
22 23
24
pre-eclampsia and intrauterine growth restriction. Ultrasound Obstet Gynecol 2008; 31: 303–309. Goetzinger KR, Zhong Y, Cahill AG, Odibo L, Macones GA, Odibo AO. Efficiency of first-trimester uterine artery Doppler, a-disintegrin and metalloprotease 12, pregnancy-associated plasma protein A, and maternal characteristics in the prediction of preeclampsia. J Ultrasound Med 2013; 32: 1593–1600. Costa SL, Proctor L, Dodd JM, Toal M, Okun N, Johnson JA et al. Screening for placental insufficiency in high-risk pregnancies: is earlier better? Placenta 2008; 29: 1034–1040. Cindrova-Davies T, Spasic-Boskovic O, Jauniaux E, Charnock-Jones DS, Burton GJ. Nuclear factor-kappa B, p38, and stress-activated protein kinase mitogen-activated protein kinase signaling pathways regulate proinflammatory cytokines and apoptosis in human placental explants in response to oxidative stress: effects of antioxidant vitamins. Am J Pathol 2007; 170: 1511–1520. Hung TH, Charnock-Jones DS, Skepper JN, Burton GJ. Secretion of tumor necrosis factor-alpha from human placental tissues induced by hypoxia-reoxygenation causes endothelial cell activation in vitro: a potential mediator of the inflammatory response in preeclampsia. Am J Pathol 2004; 164: 1049–1061. Tjoa ML, Cindrova-Davies T, Spasic-Boskovic O, Bianchi DW, Burton GJ. Trophoblastic oxidative stress and the release of cell-free feto-placental DNA. Am J Pathol 2006; 169: 400–404. Moldenhauer JS, Stanek J, Warshak C, Khoury J, SIBAI B. The frequency and severity of placental findings in women with preeclampsia are gestational age dependent. Am J Obstet Gynecol 2003; 189: 1173–1177. Egbor M, Ansari T, Morris N, Green CJ, Sibbons PD. Morphometric placental villous and vascular abnormalities in early- and late-onset pre-eclampsia with and without fetal growth restriction. BJOG 2006; 113: 580–589. Melchiorre K, Wormald B, Leslie K, Bhide A, Thilaganathan B. First-trimester uterine artery Doppler indices in term and preterm pre-eclampsia. Ultrasound Obstet Gynecol 2008; 32: 133–137. Odibo AO, Zhong Y, Longtine M, Tuuli M, Odibo L, Cahill AG et al. First-trimester serum analytes, biophysical tests and the association with pathological morphometry in the placenta of pregnancies with preeclampsia and fetal growth restriction. Placenta 2011; 32(4): 333–338. American College of Obstetricians and Gynecologists. Diagnosis and Management of Preeclampsia and Eclampsia. ACOG Practice Bulletin No. 33. ACOG: Washington, DC, USA, 2002. Report of the National High Blood Pressure Education Program Working Group. Report on high blood pressure in pregnancy. Am J Obstet Gynecol 2000; 183: S1–S22. Alexander GR, Himes JH, Kaufman RB, Mor J, Kogan MA. United States national reference for fetal growth. Obstet Gynecol 1996; 87: 163–168. Tsiartas P, Kacerovsky M, Musilova I, Hornychova H, Cobo T, Sa¨vman K et al. The association between histological chorioamnionitis, funisitis and neonatal outcome in women with preterm prelabor rupture of membranes. J Matern Fetal Neonatal Med 2013; 26: 1332–1336. Odibo AO, Zhong Y, Goetzinger KR, Odibo L, Bick JL, Bower CR et al. First-trimester placental protein 13, PAPP-A, uterine artery Doppler and maternal characteristics in the prediction of pre-eclampsia. Placenta 2011; 32(8): 598–602.
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