DOI: 10.1002/pd.4474
ORIGINAL ARTICLE
Timing of and outcomes after selective termination of anomalous fetuses in dichorionic twin pregnancies† Catherine A. Bigelow1,2, Stephanie H. Factor1,3, Erin Moshier1, Angela Bianco1, Keith A. Eddleman1 and Joanne L. Stone1 1
Department of Obstetrics, Gynecology and Reproductive Science, Division of Maternal Fetal Medicine, Icahn School of Medicine at Mount Sinai, New York, NY, USA Department of Obstetrics and Gynecology, Brigham and Women’s Hospital, Boston, MA, USA 3 Department of Medicine, Division of Infectious Disease, Icahn School of Medicine at Mount Sinai, New York, NY, USA *Correspondence to: Joanne Stone. E-mail: [email protected] † Article presentation: This work was presented as a poster presentation at the 32nd Annual Meeting of the Society for Maternal Fetal Medicine in Dallas, TX, 9 to 11 February 2012. 2
ABSTRACT Objective The objective of this article is to determine if selective termination (ST) of an anomalous dichorionic twin at early gestational age (GA) is associated with a decreased risk of fetal loss and prematurity. Method All patients who had ST for dichorionic twin pregnancies from 2004 through 2010 at Mount Sinai Medical Center were included. Data were collected via chart review and patient interview. Two case–control analyses were carried out: first, cases were nonviable deliveries, and controls were live births; and second, cases were live births 1).3 These factors are not modifiable and do not offer venues to improve outcomes. Some studies have suggested that performing ST at an earlier gestational age (GA) may decrease fetal loss, whereas other studies have not had the same results (Table 1). Evans et al., in their 1994 multicenter study, found a lower loss rate when ST was performed on all multiple birth types (monochorionic
© 2014 John Wiley & Sons, Ltd.
Timing and outcomes of selective terminal in twins
1321
twins, dichorionic twins, triplets, etc.) before 16 weeks’ GA.8 Similarly, Alvarado et al., in their 2012 study, found a lower loss rate when ST was performed on dichorionic twins prior to 18 weeks’ GA,9 but the correlation is not statistically significant. In contrast, Eddleman et al., in their 2002 study, found a higher loss rate when ST was performed on all multiple birth types at or before 20 weeks’ GA, but the correlation is not statistically significant; and Lynch et al., in their 1996 study, found an equal loss rate when ST was performed on dichorionic twins before
and at or after 20 weeks’ GA. Thus, it is still not known if GA at the time of the ST procedure is associated with fetal loss. Studies on ST have had conflicting results about the effect of earlier ST on the risk of premature delivery (Table 1). Evans et al., in their 1994 multicenter study, found that ST in all multiple birth types at or after 20 weeks increased the risk of preterm delivery ( 20 weeks’ GA in multiple birth types
79
1 (1)
78 (99)
ST ≤ 16 weeks’ GA in multiple birth types
37
2 (5)
35 (95)
ST > 16 weeks’ GA in multiple birth types
146
0.10
Eddleman et al., (2002)3 0.09
Evans et al., (1994)8
21 (14)
34 weeks
ST ≥ 18 weeks GA in dichorionic twins
15
2 (13) ≤ 34 weeks
13 (87) > 34 weeks
0.10
Eddleman et al., (2002)3 ST ≤ 20 weeks GA in all multiple birth types
112
5 (5) < 28 weeks
107 (95) ≥ 28 weeks
ST > 20 weeks GA in all multiple birth types
78
2 (3) < 28 weeks
76 (97) ≥28 weeks
ST ≤ 16 weeks GA in all multiple birth types
35
13 (37) < 37 weeks
22 (63) ≥ 37 weeks
ST > 16 weeks GA in all multiple birth types
125
54 (43) < 37 weeks
71 (57) ≥ 37 weeks
ST < 20 weeks GA in dichorionic twins
27
8 (30) < 37 weeks
19 (70) ≥ 37 weeks
ST ≥ 20 weeks GA in dichorionic twins
40
20 (50) < 37 weeks
20 (50) ≥ 37 weeks
0.70
Evans et al., (1994)8 0.52**
Lynch et al., (1996)10 0.10**
ST, selective termination; GA, gestational age. Researcher groups presented their data using different gestational ages. We have used the data as it was presented in their articles. b Fetal death(s) is excluded from the total number of ST procedures performed for this portion of the table. c P-values are taken from referenced articles if available. If P-value is unavailable in referenced article, P-value is calculated using EpiInfo 7, a free Web-based statistical program accessible at http://wwwn.cdc.gov/epiinfo (Centers for Disease Control and Prevention: Atlanta, GA, USA). *P-value is calculated using Fisher’s exact test in EpiInfo 7. **P-value is calculated using chi-squared test in EpiInfo 7. a
Prenatal Diagnosis 2014, 34, 1320–1325
© 2014 John Wiley & Sons, Ltd.
C. A. Bigelow et al.
1322
increased the risk of preterm delivery (birth
ORIGINAL ARTICLE
Timing of and outcomes after selective termination of anomalous fetuses in dichorionic twin pregnancies† Catherine A. Bigelow1,2, Stephanie H. Factor1,3, Erin Moshier1, Angela Bianco1, Keith A. Eddleman1 and Joanne L. Stone1 1
Department of Obstetrics, Gynecology and Reproductive Science, Division of Maternal Fetal Medicine, Icahn School of Medicine at Mount Sinai, New York, NY, USA Department of Obstetrics and Gynecology, Brigham and Women’s Hospital, Boston, MA, USA 3 Department of Medicine, Division of Infectious Disease, Icahn School of Medicine at Mount Sinai, New York, NY, USA *Correspondence to: Joanne Stone. E-mail: [email protected] † Article presentation: This work was presented as a poster presentation at the 32nd Annual Meeting of the Society for Maternal Fetal Medicine in Dallas, TX, 9 to 11 February 2012. 2
ABSTRACT Objective The objective of this article is to determine if selective termination (ST) of an anomalous dichorionic twin at early gestational age (GA) is associated with a decreased risk of fetal loss and prematurity. Method All patients who had ST for dichorionic twin pregnancies from 2004 through 2010 at Mount Sinai Medical Center were included. Data were collected via chart review and patient interview. Two case–control analyses were carried out: first, cases were nonviable deliveries, and controls were live births; and second, cases were live births 1).3 These factors are not modifiable and do not offer venues to improve outcomes. Some studies have suggested that performing ST at an earlier gestational age (GA) may decrease fetal loss, whereas other studies have not had the same results (Table 1). Evans et al., in their 1994 multicenter study, found a lower loss rate when ST was performed on all multiple birth types (monochorionic
© 2014 John Wiley & Sons, Ltd.
Timing and outcomes of selective terminal in twins
1321
twins, dichorionic twins, triplets, etc.) before 16 weeks’ GA.8 Similarly, Alvarado et al., in their 2012 study, found a lower loss rate when ST was performed on dichorionic twins prior to 18 weeks’ GA,9 but the correlation is not statistically significant. In contrast, Eddleman et al., in their 2002 study, found a higher loss rate when ST was performed on all multiple birth types at or before 20 weeks’ GA, but the correlation is not statistically significant; and Lynch et al., in their 1996 study, found an equal loss rate when ST was performed on dichorionic twins before
and at or after 20 weeks’ GA. Thus, it is still not known if GA at the time of the ST procedure is associated with fetal loss. Studies on ST have had conflicting results about the effect of earlier ST on the risk of premature delivery (Table 1). Evans et al., in their 1994 multicenter study, found that ST in all multiple birth types at or after 20 weeks increased the risk of preterm delivery ( 20 weeks’ GA in multiple birth types
79
1 (1)
78 (99)
ST ≤ 16 weeks’ GA in multiple birth types
37
2 (5)
35 (95)
ST > 16 weeks’ GA in multiple birth types
146
0.10
Eddleman et al., (2002)3 0.09
Evans et al., (1994)8
21 (14)
34 weeks
ST ≥ 18 weeks GA in dichorionic twins
15
2 (13) ≤ 34 weeks
13 (87) > 34 weeks
0.10
Eddleman et al., (2002)3 ST ≤ 20 weeks GA in all multiple birth types
112
5 (5) < 28 weeks
107 (95) ≥ 28 weeks
ST > 20 weeks GA in all multiple birth types
78
2 (3) < 28 weeks
76 (97) ≥28 weeks
ST ≤ 16 weeks GA in all multiple birth types
35
13 (37) < 37 weeks
22 (63) ≥ 37 weeks
ST > 16 weeks GA in all multiple birth types
125
54 (43) < 37 weeks
71 (57) ≥ 37 weeks
ST < 20 weeks GA in dichorionic twins
27
8 (30) < 37 weeks
19 (70) ≥ 37 weeks
ST ≥ 20 weeks GA in dichorionic twins
40
20 (50) < 37 weeks
20 (50) ≥ 37 weeks
0.70
Evans et al., (1994)8 0.52**
Lynch et al., (1996)10 0.10**
ST, selective termination; GA, gestational age. Researcher groups presented their data using different gestational ages. We have used the data as it was presented in their articles. b Fetal death(s) is excluded from the total number of ST procedures performed for this portion of the table. c P-values are taken from referenced articles if available. If P-value is unavailable in referenced article, P-value is calculated using EpiInfo 7, a free Web-based statistical program accessible at http://wwwn.cdc.gov/epiinfo (Centers for Disease Control and Prevention: Atlanta, GA, USA). *P-value is calculated using Fisher’s exact test in EpiInfo 7. **P-value is calculated using chi-squared test in EpiInfo 7. a
Prenatal Diagnosis 2014, 34, 1320–1325
© 2014 John Wiley & Sons, Ltd.
C. A. Bigelow et al.
1322
increased the risk of preterm delivery (birth
