http://informahealthcare.com/gye ISSN: 0951-3590 (print), 1473-0766 (electronic) Gynecol Endocrinol, 2014; 30(3): 197–201 ! 2014 Informa UK Ltd. DOI: 10.3109/09513590.2013.859242
IUI AND LUTEAL PHASE SUPPORT
Luteal phase support with progesterone in intrauterine insemination: a prospective randomized study Marı´a Inmaculada Romero Nieto1, Juan Lorente Gonza´lez1, Jose´ Eduardo Arjona-Berral1, Marı´a del Mun˜oz-Villanueva1, and Camil Castelo-Branco2 Department of Obstetrics and Gynecology, ‘‘Reina Sofı´a’’ University Hospital, Co´rdoba, Spain and 2Faculty of Medicine, Institut Clinic of Gynecology, Obstetrics and Neonatology, University of Barcelona, Hospital Clinic-Institut d´Investigacions Biome`diques August Pi i Sunyer (IDIBAPS), Barcelona, Spain Abstract
Keywords
Objective: To determine the effect of vaginal progesterone as luteal support on pregnancy outcomes in infertile patients who undergo ovulation induction with gonadotropins and intrauterine insemination (IUI). Design: Prospective randomized trial. Setting: Tertiary referral center. Patient(s): About 398 patients with primary infertility were treated during 893 ovarian stimulation and IUI cycles from February 2010 to September 2012. Methods: All patients underwent ovarian stimulation with gonadotropins combined with IUI. Patients in the supported group received vaginal micronized progesterone capsules 200 mg once daily from the day after insemination until next menstruation or continuing for up to 8 weeks of pregnancy. Women allocated in the control group did not receive luteal phase support. Main outcome measure(s): Livebirth rate, clinical pregnancy rate and early miscarriage rate per cycle. Result(s): Of the 893 cycles, a total of 111 clinical pregnancies occurred. There were no significant differences between supported with progesterone and unsupported cycle in terms of livebirth rate (10.2% versus 8.3%, respectively, with a p value ¼ 0.874) and clinical pregnancy rate (13.8% compared with 11.0% in unsupported cycle with a p value ¼ 0.248). An early miscarriage rate of 3.6% was observed in the supported cycles and 2.7% in the unsupported cycles, with no significant differences between the groups (p value ¼ 0.874). Conclusion(s): In infertile patients treated with mildly ovarian stimulation with recombinant gonadotropins and IUI, luteal phase support with vaginal progesterone is not associated with higher livebirth rate or clinical pregnancy rate compared with patients who did not receive any luteal phase support.
Infertility, intrauterine insemination, livebirth rate, luteal support, ovulation induction, pregnancy rate, progesterone
Introduction Intrauterine insemination (IUI) is still a common treatment and an effective form of improving the probability of pregnancy in couples with longstanding subfertility [1,2]. Progesterone is an essential factor for endometrial receptivity, implantation and maintenance of pregnancy [3]. Low LH levels and defective luteal phase have been detected in GnRH agonist and antagonists in vitro fertilization (IVF) cycles [4,5]. One of the most popular reasons for this defective luteal phase is the multifollicular development in controlled ovarian hyperstimulation, that results in a supraphysiological concentration of steroids in the luteal phase, leading to defective LH secretion with premature luteolysis and inadequate P secretion. In these cycles the benefit of progesterone (P) as luteal phase support has been well documented and has shown success in improving pregnancy rates [6–12]. Regarding IUI cycles, where a mild ovarian stimulation is recommended (limited to one to two follicles) [13,14] and the Address for correspondence: Camil Castelo-Branco, Institut Clı´nic de Ginecologia, Obstetrı´cia i Neonatologı´a, Hospital Clı´nic, Villarroel 170, 08036 Barcelona, Spain. Tel: +34 93 227 54 36. Fax: +34 93 227 93 25. E-mail: [email protected]
History Received 7 July 2013 Revised 29 September 2013 Accepted 22 October 2013 Published online 7 January 2014
use of GnRH analogs is normally avoided, limited data and little consensus among practitioners exist concerning the quality of the luteal phase and the use of luteal-phase support (LPS). The ESHRE Capri Workshop Group [13] (2009) concluded that LPS did not appear to be major requirement in IUI cycles; nevertheless, the addition of P became established clinical practice even in the absence of any robust evidence of effectiveness. In 2009, the prospective randomized trial by Erdem et al. [15] found out a beneficial effect of LPS with vaginal P on pregnancy rates in IUI cycles in patients with unexplained infertility. And an evidence-based review of Cohlen et al. [16], based on the Erdem trial, recommended applying luteal phase support in stimulated IUI cycles only when cost effective be proven. Moreover, in 2011, the prospective randomized study by Maher et al. [17] described that the clinical pregnancy rate per patient was higher for supported cycles with vaginal progesterone than unsupported cycles, when recombinant follicle-stimulating hormone was used for ovarian stimulation. Agha-Hosseini et al. [18], in a randomized prospective trial in 2012, demonstrated that in patients with unexplained and mild male factor infertility treated with ovarian stimulation and IUI, LPS with vaginal P was associated with significantly higher
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1
198
M. I. Romero Nieto et al.
clinical pregnancy rates compared with patients without LPS. However, two prospective randomized trials in 2010, by Kyrou et al. [19] and by Ebrahimi et al. [20], found out that routine LPS with vaginal P did not seem to improve pregnancy rates in normo-ovulatory women stimulated with clomiphene citrate for IUI cycles. The aim of this prospective randomized study is to determine whether the use of vaginal progesterone for luteal phase support can improve clinical pregnancy rate in IUI mildly stimulated cycles in infertile couples.
Materials and methods
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Sample This prospective, open, randomized trial included 398 couples with primary infertility and 999 IUI cycles. The study was conducted between February 2010 and September 2012 at the Infertility Unit of our Universitary Hospital Reina Sofı´a from Cordoba (Spain). The inclusion criteria were: duration of primary infertility at least 1 year for each couple, acceptation of use of donor sperm, ages between 18 and 40 years; body mass Index (BMI) 535 kg/m2, normal uterine cavities in transvaginal ecography and hysterosalpingography, patency of at least one fallopian tube assessed by hysterosalpingography or laparoscopic whit chromosalpingography and optimal ovarian reserve: day 3 serum folliculo-stimulating hormone (FSH) 510 UI/ml and estradiol (E2) 560 pg/ml at the initiation of stimulation. Only stimulated cycles using gonadotropins were included. The exclusion criteria include: severe/moderate endometriosis (American Fertility Society grade III/IV) [21], total motile sperm count 53 millions following semen preparation (swim up) or severe teratospermia (55% normal forms), and cycles using GnRH analogs. Any patient with contraindications to progesterone therapy or to ovulation induction was excluded as well. All couples had undergone a basic fertility workup, which included a medical history, cycle monitoring, semen analysis and assessment of tubal patency. The protocol was explained to the patients before they entered the study, and a written informed consent was obtained from all participating patients. The Ethics Committee at our hospital approved this study. Patients included in the study were randomly assigned into two groups by computer-generated random allocation. If a patient did not achieve pregnancy, she was randomized again for the next cycle. A maximum number of four cycles was reached. If a couple failed to achieve pregnancy after all attempts, they progressed to IVF. Outcomes The main outcome of the study was live birth rate per cycle, defined as the live birth of at least one baby who was living at 1 week after birth. Other secondary outcomes were: clinical pregnancy rate per cycle, defined as the presence of gestational sac on transvaginal ultrasound; early miscarriage rate per cycle, defined as the proportion of patients with initially gestational sac in whom pregnancy failed to develop by 12 weeks of gestation; ectopic pregnancy rate per cycle and multiple pregnancies rate per cycle, evaluated by transvaginal ultrasonography (TVU). Study protocol Ovarian stimulation. After inclusion in the study, before starting ovarian stimulation, all women underwent TVU on day 2–3 of the menstrual cycle in order to rule out any ovarian pathology. Ovarian stimulation started between 2nd and 4th day of the cycle. Highpurified urinary or recombinant gonadotropins were used. Ovarian
Gynecol Endocrinol, 2014; 30(3): 197–201
response was monitored by TVU starting from the 6th stimulation day. No GnRh analogs were used. When one to three dominant follicles reached 17 mm, ovulation was triggered with 6.500 UI recombinant hCG (human chorionic gonadotrophin, OvitrelleÕ , Merck-Serono, Madrid, Spain). If there were more than three dominant follicles with a mean diameter 17 mm, the cycle was canceled, in order to reduce the risk of multiple pregnancies. Semen preparation:. Semen samples were collected by masturbation in sterile containers. Liquefaction of semen was performed at 37 C, and then the concentration, volume, motility and morphology of sperm were evaluated according to World Health Organization criteria [22]. The method for semen preparation was Swim-up. The semen was taken into a tube and sperm medium (Pine Sperm Wash) was added in a proportion of 1:1. It was centrifuged at 600 g (1700 rpm) for 10 min. The supernatant was separated and 0.5 ml of sperm medium was added over the pellet and incubated for 45 min at 37 C with a 45 angle of inclination. Total motile sperm number was evaluated and the final pellet was stored in an incubator at 37 C until the time of insemination. IUI technique. IUI was performed 34 2 h after HCG administration with a disposable cannula (Gynetics Medical Products N.V. Rembert Dodoensstraat-Lommel, Belgium). The patient rested in a supine position for 10 min after the insemination. Luteal phase support. In the supported cycles, vaginal micronized P capsules 200 mg was administered once daily beginning the day after IUI and continuing until next menstruation, or until 8 weeks of gestation. Patients in the unsupported cycles did not receive any luteal phase support. Pregnancy evaluation. Pregnancy testing was performed at 15–16 days after the IUI, and all patients with positive pregnancy test results underwent TVU at 6–7 weeks of gestation in order to confirm an intrauterine gestation, and detect the number of sacs and embryonic viability. Statistical analysis Statistical analysis was performed by using the Statistical Program PASW Statistic 18 (SPSS Inc., Chicago, IL). Quantitative data are expressed as mean (m) standard deviation (SD), minimum y maximum values, and median (me) interquartile range (IQR). Qualitative data are presented as counts(c) and percentages (%). Comparison of the baseline characteristics and outcomes between the two groups were performed by Mann–Whitney U test (to compare mean values) and chi-squared test (to compare proportions) using contingency tables (Yates´ correction was used for the 2 2 tables and the Fisher exact test was applied when any expected frequency was 55). Outcomes were calculated per cycles. Statistical significance was set at p value50.05.
Results During the study period, 406 patients undergoing IUI and 999 cycles were commenced. Up to 106 cycles starting ovulation induction (10.6%) were further excluded due to motile sperm count 53 millions following semen preparation on the day of IUI (75 cycles) or IUD not possible (31 cycles). No patients abandoned due to a poor response to ovarian stimulation (absence of follicle) or ovarian hyperstimulation. Finally, a total of 893 cycles were analyzed in 398 patients. Vaginal P was used in 449 cycles, compared with 444 unsupported cycles.
Vaginal progesterone does not improve IUI outcomes
DOI: 10.3109/09513590.2013.859242
Demographic, baseline characteristics and stimulation data of the study patients are shown in Table 1. There were no differences between the two groups in female age, days of stimulation and capacited sperm (Table 1). The infertility diagnosis, type of sperm, number of dominant follicles and drugs used for induction ovulation in each group were also comparable. Pregnancy outcomes are shown in Figure 1 and Table 2. Of the 893 cycles, a total of 111 clinical pregnancies occurred. There
were 62 pregnancies in the group supported with progesterone and 49 in the unsupported group. Of the 111 pregnancies, 49 were after the first cycle (44.1%), 27 after the second and 22 after the third and 13 after the fourth. There were no differences between supported and unsupported group in terms of livebirth rate per cycle (10.2% versus 8.3%, respectively, p ¼ 0.874) and clinical pregnancy rate per cycle (13.8% versus 11.0%; p ¼ 0.248). There were also no significant differences between supported and unsupported group in livebirth
Table 1. Baseline characteristics of unsupported and supported cycles. Unsupported cycles1
Characteristic Female age (years)
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Days of stimulation
Capacited sperm (106/ml)
Infertility diagnosis
Type of sperm No. of dominant follicles
Drugs used for induction ovulation
199
Supported cycles1
p*
m SD me IQR Min–max
33.1 3.3 34.0 5 22–39
32.9 3.4 33.0 4 21–40
0.277
m SD me IQR Min–max
8.0 2.6 7.0 3 3–26
8.2 2.7 8.0 3 4–22
0.145
m SD me IQR Min–max
57.6 88.5 23.2 44.4 3–646
53.9 79.8 25.5 40.6 3–775
0.536
Female factor Unexplain infertility Male factor Mixed infertility No male partner
34 146 185 35 44
54 139 194 30 31
Partner sperm Donor sperm
333 (75.0%) 111 (25.0%)
358 (79.7%) 91 (20.3%)
one two three
284 (64.0%) 143 (32.2%) 17 (3.8%)
285 (63.5%) 142 (31.6%) 22 (4.9%)
Follitropin alfa Follitropin beta Urofollitropin Menotropin
93 102 90 159
111 94 81 163
(7.7%) (32.9%) (41.7%) (7.9%) (9.9%)
(20.9%)) (23.0%) (20.3%) (35.8%)
(12.0%) (31.0%) (43.2%) (6.7%) (6.9%)
(24.8%) (20.9%) (18.0%) (36.4%)
0.116
0.107 0.734
0.148
Quantitative data are expressed as mean (m); standard deviation (SD); median (me); interquartile range (IQR) and, minimum–maximum (min–max).1Qualitative data are expressed as counts (percentage). p*: level of statistical significance obtained by Mann–Whitney U test and chi-squared test.
Randomized n=893 cycles
Luteal support
No luteal support
n=449
n=444
Pregnant
Not pregnant
Pregnant
Not pregnant
n=62/449
n= 387/449
n= 49/444
n=395/444
Live births
Live births
n=46/449
n=37/444
Early miscarriages
Early miscarriage
n= 16/449
n=12/444
Figure 1. Flow chart for study patients.
M. I. Romero Nieto et al.
Unexplained infertility Male factor Female factor No male partner 2013 Romero MI et al.
893 (398)
1.4/1.4
2.9/2.7 1.6/1.4 2012 Agha-Hosseini M et al.
290 (290)
1.5/1.5 2.0/2.2 2–3/2–3 2010 2011 Ebrahimi M et al Maher MA
511 (200) 258 (71)
2009 2010 Erdem A et al. Kyrou D et al.
S, supported with progesterone group; US, unsupported group; CC, clomiphene citrate; L, letrozole; hMG, human menopausal gonadotropin; FHSr, recombinant FSH; FSHu, urinary FSH ultrapurified; NS, no significant difference; p*: statistical significance value (chi-squared test). yThere were one quadruplet in the study group and one quadruplet in the control group. zIn the study by Maher, livebirth rate per cycle and per patient, and clinical pregnancy rate per patient were significant, only clinical pregnancy rate per cycle was not significant.
NS 0.2 1.1 2.7 3.6 11.0 8.3 10.2
13.8
0.027 1.40 2.02 4.22 5.40 14.1 –
CC L CC þ hMG L þ hMG FSHr FSHu hMG
–
24.3
NS 0.07z 10.3 0.0 8.5 3.0 – 5.6 – 5.3 10.03 19.8 11.5 29.5 5.7 5.5 7.5 18.9 CC/hMG FSHr
1.96y 1.0 1.34y 0.5 4.4 2.0 7.7 1.5 12.7 11.3 21.1 10.2 9.3 9.3 17.4 8.7 FSHr CC
Unexplained infertility Unexplained infertility Male factor No male partner Unexplained infertility Unexplained infertility Male factor Female factor Unexplained infertility Male factor Female factor 2.9/2.8 0.3/0.3 1.6/1.5 1.2/1.3
US Infertility diagnosis
Drugs used for stimulation No. of follicles 9–16 mm S/US No. of follicles 17 mm S/US N cycles (patient)
Intrauterine insemination is one of the most used techniques to enhance the probability of conception in subfertile couples. One of the still unresolved issues in this technique is the necessity for luteal phase support. From studies with IVF cycles, it is well known that controlled ovarian hyperstimulation produces a deficient luteal phase probably due to the existence of a large number of corpora lutea. However, a mildly ovarian stimulation is normally used in IUI cycles, whose aim is to produce a small number of follicles (one to three). It is especially in these cases with lesser number of corpora lutea where remains unanswered the question whether exists a deficiency of the luteal phase. Up until now, there are only five randomized clinical trials that have studied this issue (Table 3). There is a lack of homogeneity between these studies and they reach different conclusions, therefore it is not possible to establish any clear criteria from them. Our study is the clinical trial that involved the largest number of IUI cycles to date, in which it has been compared exclusively mildly stimulated cycles with gonadotropins. Our results show that there is no significant difference between IUI cycles with luteal phase support and those without luteal support in any of the studied parameters (livebirth, clinical pregnancy, early miscarriage or multiple pregnancy rates). These results remain regardless the study subgroups performed (cause of infertility, number of follicles 17 mm on the day of hCG administration, type of gonadotropin used, or type of sperm, partner or donor). These findings suggest that there is probably some subgroup of cycles or patients who could benefit themselves from the administration of progesterone in luteal phase, although this subgroup has not been identified yet. Related to this, it is noteworthy that studying subgroups of cycles with a higher stimulation (two or three dominant follicles instead of one), the difference in the clinical pregnancy rate increased in the study groups. Thus, the clinical pregnancy rate in mildly stimulated cycles (one dominant follicle) was 12.3% in the supported group and 10.9% in the unsupported group (a difference of 1.4%); whereas in higher stimulated cycles (two to three dominant follicles) the clinical pregnancy rate was 16.5% in supported group and 11.3% in unsupported group (an increase of 5.2%), although the differences did not reach statistical significance (p ¼ 0.706 and p ¼ 0.232, respectively). Our results agree with the results observed by Kyrou [19] and Ebrahimi [20], despite the fact that, among all these studies there
Livebirth rate per cycle
Discussion
427 (214) 400 (400)
Miscarriage rate per cycle Clinical pregnancy rate per cycle
rate (11.3% versus 7.2%; p ¼ 0.379) or clinical pregnancy rate 14.2% versus 10.3%; p ¼ 0.302). An early miscarriage rate of 3.6% was observed in the supported cycles and 2.7% in the unsupported cycles, with no significant differences between the groups (p value ¼ 0.874). No ectopic pregnancy was observed in any group and six cases of multiple pregnancies, all twins (five in the supported cycles and one in the unsupported cycles) were recorded.
Table 3. Luteal phase support in stimulated cycles of IUI: randomized clinical trials.
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yValues are counts (percentage). p*: level of statistical significance obtained by chi-squared test.
S
0.332
US
1/49 (0.2%)
S
5/62 (1.1%)
US
0.248 0.874 0.874
S
49/444 (11.0%) 12/444 (2.7%) 37/444 (8.3%)
US
p*
62/449 (13.8%) 16/449 (3.6%) 46/449 (10.2%)
S
Unsupported cycley
Year
Clinical pregnancy rate Early miscarriage rate Livebirth rate including multiple pregnancies Multiple pregnancy rate
Supported cyclesy
Author
Pregnancy outcome
Multiple pregnancy rate per cycle
Table 2. Pregnancy outcomes per cycle.
0.028 NS
Gynecol Endocrinol, 2014; 30(3): 197–201
p* (S versus US in clinical pregnancy rates per cycle)
200
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DOI: 10.3109/09513590.2013.859242
are evident methodological differences about the drugs used for ovarian stimulation and the number of dominant follicles. In all of them there were no statistically significant differences in terms of the livebirth rate, clinical pregnancy rate, and miscarriage rate between the group with luteal phase support and the group without luteal phase support. On the contrary, other three randomized trials appear to reach opposite conclusions. Thus, the study by Erdem [15], which analyzed 427 IUI cycles stimulated with recombinant gonadotropins and was performed in 214 couples with unexplained infertility, described the opposite conclusion than ours. It should be mentioned that in this study, despite using a cycle cancellation criteria similar to ours (more than three dominant follicles), the number of dominant follicles and the twin pregnancy rate were significantly higher than in our study, and incomprehensibly they obtained two cases of quadruplet pregnancies. These results suggest that the level of stimulation of their patients was probably higher than ours, which may partly explain the difference in results. The same applies to other two studies that showed opposite results than we describe in our study (Maher [17] and Agha-Hosseini [18], Table 3). A possible negative aspect of our study is that we did not perform any progesterone plasma assay in any patient. We have not considered this issue necessary because it has already been shown that midluteal serum P levels are not always directly associated with luteal function [23]. Furthermore, we have assumed that this drawback does not affect our results due to our study is a randomized design, and the study involves a large number of cycles. On the other hand, we preferred not to overload the daily activity of our unit. Our results support that nowadays do not exist any robust evidence for the widespread use of progesterone as luteal phase support in mildly stimulated IUI cycles. The trend towards a higher clinical pregnancy rate in cycles supported with progesterone in all trials made up until now could explain that there may be a subgroup of cycles or patients which could benefit from this treatment, although to date that subgroup has not been identified yet. In conclusion, at the moment, on the basis that it is well documented that stimulated IVF cycles need LPS and due to the results of our study, progesterone supplementation should be administered only in those IUI cycles with a highly ovarian stimulation (more than one dominant follicle, or one dominant follicle plus several intermediate follicles), although we recognize the absence of robust evidence for this protocol. Further randomized trials with different subgroups are needed to establish which patients or IUI cycles can benefit from the use of progesterone in luteal phase.
Declaration of interest The authors report no conflicts of interest. The authors alone are responsible for the content and writing of this article.
References 1. Cantineau AEP, Cohlen BJ. Ovarian stimulation protocols (antioestrogens, gonadotrophins with and without GnRH agonists/ antagonists) for intrauterine insemination (IUI) in women with subfertility. Cochrane Database of Syst Rev 2007;2:CD005356. 2. Hughes EG. The effectiveness of ovulation induction and intrauterine insemination in the treatment of persistent infertility: a metaanalysis. Hum Reprod 1997;12:1865–72.
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3. Bourgain C, Devroey P, Van Waesberghe L, et al. Effects of natural progesterone on the morphology of the endometrium in patients with primary ovarian failure. Hum Reprod 1990;5:537–43. 4. Kolibianakis EM, Devroey P. The luteal phase after ovarian stimulation. Reprod Biomed Online 2002;5:26–35. 5. Fauser BC, Devroey P. Reproductive biology and IVF: ovarian stimulation and luteal phase consequences. Trends Endocrinol Metab 2003;14:236–42. 6. Pritts EA, Atwood AK. Luteal phase support in infertility treatment: a meta-analysis of the randomized trials. Hum Reprod 2002;17: 2287–99. 7. The Practice Committee of the American Society for Reproductive Medicine. Progesterone supplementation during the luteal phase and in early pregnancy in the treatment of infertility: an educational bulletin. Fertil Steril 2008;89:789–92. 8. Van der Linden M, Buckingham K. Luteal phase support for assisted reproduction cycles. Cochrane Database Syst Rev 2011;10: CD009154. 9. Var T, Tanguc EA, Doganay M, et al. A comparison of the effects of three different luteal phase support protocols on in vitro fertilization outcomes: a randomized clinical trial. Fertil Steril 2011;95:985–9. 10. Check JH. Luteal phase support for in vitro fertilization-embryo transfer – present and future methods to improve successful implantation. Clin Exp Obstet Gynecol 2012;39:422–8. 11. Vaisbuch E, Leong M, Shoham Z. Progesterone support in IVF: is evidence-based medicine translated to clinical practice? A worldwide web-based survey. Reprod Biomed Online 2012;25:139–45. 12. Fatemi HM, Polyzos NP, Van Vaerenbergh I, et al. Early luteal phase endocrine profile is affected by the mode of triggering final oocyte maturation and the luteal phase support used in recombinant folliclestimulating hormone–gonadotropin-releasing hormone antagonist in vitro fertilization cycles. Fertil Steril 2013;100:742–7. 13. The ESHRE Capri Workshop Group. Intrauterine insemination. Hum Reprod Update 2009;15:265–77. 14. Van Rumste MM, Custer IM, van der Veen F, et al. The influence of the number of follicles on pregnancy rates in intrauterine insemination with ovarian stimulation: a meta-analysis. Hum Reproduction Update 2008;14:563–70. 15. Erdem A, Erdem M, Atmaca S, Guler I. Impact of luteal phase support on pregnancy rates in intrauterine insemination cycles: a prospective randomized study. Fertil Steril 2009;91:2508–13. 16. Cohlen BJ. Should luteal phase support be introduced in ovarian stimulation/IUI programmes? An evidence-based review. Reprod Biomed Online 2009;19(Suppl 4):4239. 17. Maher MA. Luteal phase support may improve pregnancy outcomes during intrauterine insemination cycles. Eur J Obstet Gynecol Reprod Biol 2011;157:57–62. 18. Agha-Hosseini M, Rahmani M, Alleyassin A, et al. The effect of progesterone supplementation on pregnancy rates in controlled ovarian stimulation and intrauterine insemination cycles: a randomized prospective trial. Eur J Obstet Gynecol Reprod Biol 2012; 165:249–53. 19. Kyrou D, Fatemi HM, Tournaye H, Devroey P. Luteal phase support in normoovulatory women stimulated with clomiphene citrate for intrauterine insemination: need or habit? Hum Reprod 2010;25: 2501–6. 20. Ebrahimi M, Asbagh FA, Darvish S. The effect of luteal phase support on pregnancy rates of the stimulated intrauterine insemination cycles in couples with unexplained infertility. Int J Fertil Steril 2010;4:51–6. 21. American Society for Reproductive Medicina. Revised American Society for Reproductive Medicine classification of endometriosis: 1996. Fertil Steril 1997;67:817–21. 22. World Health Organization. WHO laboratory manual for the examination of human semen and semen-cervical mucus interaction. 4th ed. Cambridge: Cambridge University Press; 1999. 23. Olson JL, Reprod RW, Schreiber JR, Vaitukaitis YL. Shortened luteal phase after ovulation induction with human menopausal gonadotropin and chorionic gonadotropin. Fertil Steril 1983;39: 284–91.
IUI AND LUTEAL PHASE SUPPORT
Luteal phase support with progesterone in intrauterine insemination: a prospective randomized study Marı´a Inmaculada Romero Nieto1, Juan Lorente Gonza´lez1, Jose´ Eduardo Arjona-Berral1, Marı´a del Mun˜oz-Villanueva1, and Camil Castelo-Branco2 Department of Obstetrics and Gynecology, ‘‘Reina Sofı´a’’ University Hospital, Co´rdoba, Spain and 2Faculty of Medicine, Institut Clinic of Gynecology, Obstetrics and Neonatology, University of Barcelona, Hospital Clinic-Institut d´Investigacions Biome`diques August Pi i Sunyer (IDIBAPS), Barcelona, Spain Abstract
Keywords
Objective: To determine the effect of vaginal progesterone as luteal support on pregnancy outcomes in infertile patients who undergo ovulation induction with gonadotropins and intrauterine insemination (IUI). Design: Prospective randomized trial. Setting: Tertiary referral center. Patient(s): About 398 patients with primary infertility were treated during 893 ovarian stimulation and IUI cycles from February 2010 to September 2012. Methods: All patients underwent ovarian stimulation with gonadotropins combined with IUI. Patients in the supported group received vaginal micronized progesterone capsules 200 mg once daily from the day after insemination until next menstruation or continuing for up to 8 weeks of pregnancy. Women allocated in the control group did not receive luteal phase support. Main outcome measure(s): Livebirth rate, clinical pregnancy rate and early miscarriage rate per cycle. Result(s): Of the 893 cycles, a total of 111 clinical pregnancies occurred. There were no significant differences between supported with progesterone and unsupported cycle in terms of livebirth rate (10.2% versus 8.3%, respectively, with a p value ¼ 0.874) and clinical pregnancy rate (13.8% compared with 11.0% in unsupported cycle with a p value ¼ 0.248). An early miscarriage rate of 3.6% was observed in the supported cycles and 2.7% in the unsupported cycles, with no significant differences between the groups (p value ¼ 0.874). Conclusion(s): In infertile patients treated with mildly ovarian stimulation with recombinant gonadotropins and IUI, luteal phase support with vaginal progesterone is not associated with higher livebirth rate or clinical pregnancy rate compared with patients who did not receive any luteal phase support.
Infertility, intrauterine insemination, livebirth rate, luteal support, ovulation induction, pregnancy rate, progesterone
Introduction Intrauterine insemination (IUI) is still a common treatment and an effective form of improving the probability of pregnancy in couples with longstanding subfertility [1,2]. Progesterone is an essential factor for endometrial receptivity, implantation and maintenance of pregnancy [3]. Low LH levels and defective luteal phase have been detected in GnRH agonist and antagonists in vitro fertilization (IVF) cycles [4,5]. One of the most popular reasons for this defective luteal phase is the multifollicular development in controlled ovarian hyperstimulation, that results in a supraphysiological concentration of steroids in the luteal phase, leading to defective LH secretion with premature luteolysis and inadequate P secretion. In these cycles the benefit of progesterone (P) as luteal phase support has been well documented and has shown success in improving pregnancy rates [6–12]. Regarding IUI cycles, where a mild ovarian stimulation is recommended (limited to one to two follicles) [13,14] and the Address for correspondence: Camil Castelo-Branco, Institut Clı´nic de Ginecologia, Obstetrı´cia i Neonatologı´a, Hospital Clı´nic, Villarroel 170, 08036 Barcelona, Spain. Tel: +34 93 227 54 36. Fax: +34 93 227 93 25. E-mail: [email protected]
History Received 7 July 2013 Revised 29 September 2013 Accepted 22 October 2013 Published online 7 January 2014
use of GnRH analogs is normally avoided, limited data and little consensus among practitioners exist concerning the quality of the luteal phase and the use of luteal-phase support (LPS). The ESHRE Capri Workshop Group [13] (2009) concluded that LPS did not appear to be major requirement in IUI cycles; nevertheless, the addition of P became established clinical practice even in the absence of any robust evidence of effectiveness. In 2009, the prospective randomized trial by Erdem et al. [15] found out a beneficial effect of LPS with vaginal P on pregnancy rates in IUI cycles in patients with unexplained infertility. And an evidence-based review of Cohlen et al. [16], based on the Erdem trial, recommended applying luteal phase support in stimulated IUI cycles only when cost effective be proven. Moreover, in 2011, the prospective randomized study by Maher et al. [17] described that the clinical pregnancy rate per patient was higher for supported cycles with vaginal progesterone than unsupported cycles, when recombinant follicle-stimulating hormone was used for ovarian stimulation. Agha-Hosseini et al. [18], in a randomized prospective trial in 2012, demonstrated that in patients with unexplained and mild male factor infertility treated with ovarian stimulation and IUI, LPS with vaginal P was associated with significantly higher
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1
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clinical pregnancy rates compared with patients without LPS. However, two prospective randomized trials in 2010, by Kyrou et al. [19] and by Ebrahimi et al. [20], found out that routine LPS with vaginal P did not seem to improve pregnancy rates in normo-ovulatory women stimulated with clomiphene citrate for IUI cycles. The aim of this prospective randomized study is to determine whether the use of vaginal progesterone for luteal phase support can improve clinical pregnancy rate in IUI mildly stimulated cycles in infertile couples.
Materials and methods
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Sample This prospective, open, randomized trial included 398 couples with primary infertility and 999 IUI cycles. The study was conducted between February 2010 and September 2012 at the Infertility Unit of our Universitary Hospital Reina Sofı´a from Cordoba (Spain). The inclusion criteria were: duration of primary infertility at least 1 year for each couple, acceptation of use of donor sperm, ages between 18 and 40 years; body mass Index (BMI) 535 kg/m2, normal uterine cavities in transvaginal ecography and hysterosalpingography, patency of at least one fallopian tube assessed by hysterosalpingography or laparoscopic whit chromosalpingography and optimal ovarian reserve: day 3 serum folliculo-stimulating hormone (FSH) 510 UI/ml and estradiol (E2) 560 pg/ml at the initiation of stimulation. Only stimulated cycles using gonadotropins were included. The exclusion criteria include: severe/moderate endometriosis (American Fertility Society grade III/IV) [21], total motile sperm count 53 millions following semen preparation (swim up) or severe teratospermia (55% normal forms), and cycles using GnRH analogs. Any patient with contraindications to progesterone therapy or to ovulation induction was excluded as well. All couples had undergone a basic fertility workup, which included a medical history, cycle monitoring, semen analysis and assessment of tubal patency. The protocol was explained to the patients before they entered the study, and a written informed consent was obtained from all participating patients. The Ethics Committee at our hospital approved this study. Patients included in the study were randomly assigned into two groups by computer-generated random allocation. If a patient did not achieve pregnancy, she was randomized again for the next cycle. A maximum number of four cycles was reached. If a couple failed to achieve pregnancy after all attempts, they progressed to IVF. Outcomes The main outcome of the study was live birth rate per cycle, defined as the live birth of at least one baby who was living at 1 week after birth. Other secondary outcomes were: clinical pregnancy rate per cycle, defined as the presence of gestational sac on transvaginal ultrasound; early miscarriage rate per cycle, defined as the proportion of patients with initially gestational sac in whom pregnancy failed to develop by 12 weeks of gestation; ectopic pregnancy rate per cycle and multiple pregnancies rate per cycle, evaluated by transvaginal ultrasonography (TVU). Study protocol Ovarian stimulation. After inclusion in the study, before starting ovarian stimulation, all women underwent TVU on day 2–3 of the menstrual cycle in order to rule out any ovarian pathology. Ovarian stimulation started between 2nd and 4th day of the cycle. Highpurified urinary or recombinant gonadotropins were used. Ovarian
Gynecol Endocrinol, 2014; 30(3): 197–201
response was monitored by TVU starting from the 6th stimulation day. No GnRh analogs were used. When one to three dominant follicles reached 17 mm, ovulation was triggered with 6.500 UI recombinant hCG (human chorionic gonadotrophin, OvitrelleÕ , Merck-Serono, Madrid, Spain). If there were more than three dominant follicles with a mean diameter 17 mm, the cycle was canceled, in order to reduce the risk of multiple pregnancies. Semen preparation:. Semen samples were collected by masturbation in sterile containers. Liquefaction of semen was performed at 37 C, and then the concentration, volume, motility and morphology of sperm were evaluated according to World Health Organization criteria [22]. The method for semen preparation was Swim-up. The semen was taken into a tube and sperm medium (Pine Sperm Wash) was added in a proportion of 1:1. It was centrifuged at 600 g (1700 rpm) for 10 min. The supernatant was separated and 0.5 ml of sperm medium was added over the pellet and incubated for 45 min at 37 C with a 45 angle of inclination. Total motile sperm number was evaluated and the final pellet was stored in an incubator at 37 C until the time of insemination. IUI technique. IUI was performed 34 2 h after HCG administration with a disposable cannula (Gynetics Medical Products N.V. Rembert Dodoensstraat-Lommel, Belgium). The patient rested in a supine position for 10 min after the insemination. Luteal phase support. In the supported cycles, vaginal micronized P capsules 200 mg was administered once daily beginning the day after IUI and continuing until next menstruation, or until 8 weeks of gestation. Patients in the unsupported cycles did not receive any luteal phase support. Pregnancy evaluation. Pregnancy testing was performed at 15–16 days after the IUI, and all patients with positive pregnancy test results underwent TVU at 6–7 weeks of gestation in order to confirm an intrauterine gestation, and detect the number of sacs and embryonic viability. Statistical analysis Statistical analysis was performed by using the Statistical Program PASW Statistic 18 (SPSS Inc., Chicago, IL). Quantitative data are expressed as mean (m) standard deviation (SD), minimum y maximum values, and median (me) interquartile range (IQR). Qualitative data are presented as counts(c) and percentages (%). Comparison of the baseline characteristics and outcomes between the two groups were performed by Mann–Whitney U test (to compare mean values) and chi-squared test (to compare proportions) using contingency tables (Yates´ correction was used for the 2 2 tables and the Fisher exact test was applied when any expected frequency was 55). Outcomes were calculated per cycles. Statistical significance was set at p value50.05.
Results During the study period, 406 patients undergoing IUI and 999 cycles were commenced. Up to 106 cycles starting ovulation induction (10.6%) were further excluded due to motile sperm count 53 millions following semen preparation on the day of IUI (75 cycles) or IUD not possible (31 cycles). No patients abandoned due to a poor response to ovarian stimulation (absence of follicle) or ovarian hyperstimulation. Finally, a total of 893 cycles were analyzed in 398 patients. Vaginal P was used in 449 cycles, compared with 444 unsupported cycles.
Vaginal progesterone does not improve IUI outcomes
DOI: 10.3109/09513590.2013.859242
Demographic, baseline characteristics and stimulation data of the study patients are shown in Table 1. There were no differences between the two groups in female age, days of stimulation and capacited sperm (Table 1). The infertility diagnosis, type of sperm, number of dominant follicles and drugs used for induction ovulation in each group were also comparable. Pregnancy outcomes are shown in Figure 1 and Table 2. Of the 893 cycles, a total of 111 clinical pregnancies occurred. There
were 62 pregnancies in the group supported with progesterone and 49 in the unsupported group. Of the 111 pregnancies, 49 were after the first cycle (44.1%), 27 after the second and 22 after the third and 13 after the fourth. There were no differences between supported and unsupported group in terms of livebirth rate per cycle (10.2% versus 8.3%, respectively, p ¼ 0.874) and clinical pregnancy rate per cycle (13.8% versus 11.0%; p ¼ 0.248). There were also no significant differences between supported and unsupported group in livebirth
Table 1. Baseline characteristics of unsupported and supported cycles. Unsupported cycles1
Characteristic Female age (years)
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Days of stimulation
Capacited sperm (106/ml)
Infertility diagnosis
Type of sperm No. of dominant follicles
Drugs used for induction ovulation
199
Supported cycles1
p*
m SD me IQR Min–max
33.1 3.3 34.0 5 22–39
32.9 3.4 33.0 4 21–40
0.277
m SD me IQR Min–max
8.0 2.6 7.0 3 3–26
8.2 2.7 8.0 3 4–22
0.145
m SD me IQR Min–max
57.6 88.5 23.2 44.4 3–646
53.9 79.8 25.5 40.6 3–775
0.536
Female factor Unexplain infertility Male factor Mixed infertility No male partner
34 146 185 35 44
54 139 194 30 31
Partner sperm Donor sperm
333 (75.0%) 111 (25.0%)
358 (79.7%) 91 (20.3%)
one two three
284 (64.0%) 143 (32.2%) 17 (3.8%)
285 (63.5%) 142 (31.6%) 22 (4.9%)
Follitropin alfa Follitropin beta Urofollitropin Menotropin
93 102 90 159
111 94 81 163
(7.7%) (32.9%) (41.7%) (7.9%) (9.9%)
(20.9%)) (23.0%) (20.3%) (35.8%)
(12.0%) (31.0%) (43.2%) (6.7%) (6.9%)
(24.8%) (20.9%) (18.0%) (36.4%)
0.116
0.107 0.734
0.148
Quantitative data are expressed as mean (m); standard deviation (SD); median (me); interquartile range (IQR) and, minimum–maximum (min–max).1Qualitative data are expressed as counts (percentage). p*: level of statistical significance obtained by Mann–Whitney U test and chi-squared test.
Randomized n=893 cycles
Luteal support
No luteal support
n=449
n=444
Pregnant
Not pregnant
Pregnant
Not pregnant
n=62/449
n= 387/449
n= 49/444
n=395/444
Live births
Live births
n=46/449
n=37/444
Early miscarriages
Early miscarriage
n= 16/449
n=12/444
Figure 1. Flow chart for study patients.
M. I. Romero Nieto et al.
Unexplained infertility Male factor Female factor No male partner 2013 Romero MI et al.
893 (398)
1.4/1.4
2.9/2.7 1.6/1.4 2012 Agha-Hosseini M et al.
290 (290)
1.5/1.5 2.0/2.2 2–3/2–3 2010 2011 Ebrahimi M et al Maher MA
511 (200) 258 (71)
2009 2010 Erdem A et al. Kyrou D et al.
S, supported with progesterone group; US, unsupported group; CC, clomiphene citrate; L, letrozole; hMG, human menopausal gonadotropin; FHSr, recombinant FSH; FSHu, urinary FSH ultrapurified; NS, no significant difference; p*: statistical significance value (chi-squared test). yThere were one quadruplet in the study group and one quadruplet in the control group. zIn the study by Maher, livebirth rate per cycle and per patient, and clinical pregnancy rate per patient were significant, only clinical pregnancy rate per cycle was not significant.
NS 0.2 1.1 2.7 3.6 11.0 8.3 10.2
13.8
0.027 1.40 2.02 4.22 5.40 14.1 –
CC L CC þ hMG L þ hMG FSHr FSHu hMG
–
24.3
NS 0.07z 10.3 0.0 8.5 3.0 – 5.6 – 5.3 10.03 19.8 11.5 29.5 5.7 5.5 7.5 18.9 CC/hMG FSHr
1.96y 1.0 1.34y 0.5 4.4 2.0 7.7 1.5 12.7 11.3 21.1 10.2 9.3 9.3 17.4 8.7 FSHr CC
Unexplained infertility Unexplained infertility Male factor No male partner Unexplained infertility Unexplained infertility Male factor Female factor Unexplained infertility Male factor Female factor 2.9/2.8 0.3/0.3 1.6/1.5 1.2/1.3
US Infertility diagnosis
Drugs used for stimulation No. of follicles 9–16 mm S/US No. of follicles 17 mm S/US N cycles (patient)
Intrauterine insemination is one of the most used techniques to enhance the probability of conception in subfertile couples. One of the still unresolved issues in this technique is the necessity for luteal phase support. From studies with IVF cycles, it is well known that controlled ovarian hyperstimulation produces a deficient luteal phase probably due to the existence of a large number of corpora lutea. However, a mildly ovarian stimulation is normally used in IUI cycles, whose aim is to produce a small number of follicles (one to three). It is especially in these cases with lesser number of corpora lutea where remains unanswered the question whether exists a deficiency of the luteal phase. Up until now, there are only five randomized clinical trials that have studied this issue (Table 3). There is a lack of homogeneity between these studies and they reach different conclusions, therefore it is not possible to establish any clear criteria from them. Our study is the clinical trial that involved the largest number of IUI cycles to date, in which it has been compared exclusively mildly stimulated cycles with gonadotropins. Our results show that there is no significant difference between IUI cycles with luteal phase support and those without luteal support in any of the studied parameters (livebirth, clinical pregnancy, early miscarriage or multiple pregnancy rates). These results remain regardless the study subgroups performed (cause of infertility, number of follicles 17 mm on the day of hCG administration, type of gonadotropin used, or type of sperm, partner or donor). These findings suggest that there is probably some subgroup of cycles or patients who could benefit themselves from the administration of progesterone in luteal phase, although this subgroup has not been identified yet. Related to this, it is noteworthy that studying subgroups of cycles with a higher stimulation (two or three dominant follicles instead of one), the difference in the clinical pregnancy rate increased in the study groups. Thus, the clinical pregnancy rate in mildly stimulated cycles (one dominant follicle) was 12.3% in the supported group and 10.9% in the unsupported group (a difference of 1.4%); whereas in higher stimulated cycles (two to three dominant follicles) the clinical pregnancy rate was 16.5% in supported group and 11.3% in unsupported group (an increase of 5.2%), although the differences did not reach statistical significance (p ¼ 0.706 and p ¼ 0.232, respectively). Our results agree with the results observed by Kyrou [19] and Ebrahimi [20], despite the fact that, among all these studies there
Livebirth rate per cycle
Discussion
427 (214) 400 (400)
Miscarriage rate per cycle Clinical pregnancy rate per cycle
rate (11.3% versus 7.2%; p ¼ 0.379) or clinical pregnancy rate 14.2% versus 10.3%; p ¼ 0.302). An early miscarriage rate of 3.6% was observed in the supported cycles and 2.7% in the unsupported cycles, with no significant differences between the groups (p value ¼ 0.874). No ectopic pregnancy was observed in any group and six cases of multiple pregnancies, all twins (five in the supported cycles and one in the unsupported cycles) were recorded.
Table 3. Luteal phase support in stimulated cycles of IUI: randomized clinical trials.
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yValues are counts (percentage). p*: level of statistical significance obtained by chi-squared test.
S
0.332
US
1/49 (0.2%)
S
5/62 (1.1%)
US
0.248 0.874 0.874
S
49/444 (11.0%) 12/444 (2.7%) 37/444 (8.3%)
US
p*
62/449 (13.8%) 16/449 (3.6%) 46/449 (10.2%)
S
Unsupported cycley
Year
Clinical pregnancy rate Early miscarriage rate Livebirth rate including multiple pregnancies Multiple pregnancy rate
Supported cyclesy
Author
Pregnancy outcome
Multiple pregnancy rate per cycle
Table 2. Pregnancy outcomes per cycle.
0.028 NS
Gynecol Endocrinol, 2014; 30(3): 197–201
p* (S versus US in clinical pregnancy rates per cycle)
200
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DOI: 10.3109/09513590.2013.859242
are evident methodological differences about the drugs used for ovarian stimulation and the number of dominant follicles. In all of them there were no statistically significant differences in terms of the livebirth rate, clinical pregnancy rate, and miscarriage rate between the group with luteal phase support and the group without luteal phase support. On the contrary, other three randomized trials appear to reach opposite conclusions. Thus, the study by Erdem [15], which analyzed 427 IUI cycles stimulated with recombinant gonadotropins and was performed in 214 couples with unexplained infertility, described the opposite conclusion than ours. It should be mentioned that in this study, despite using a cycle cancellation criteria similar to ours (more than three dominant follicles), the number of dominant follicles and the twin pregnancy rate were significantly higher than in our study, and incomprehensibly they obtained two cases of quadruplet pregnancies. These results suggest that the level of stimulation of their patients was probably higher than ours, which may partly explain the difference in results. The same applies to other two studies that showed opposite results than we describe in our study (Maher [17] and Agha-Hosseini [18], Table 3). A possible negative aspect of our study is that we did not perform any progesterone plasma assay in any patient. We have not considered this issue necessary because it has already been shown that midluteal serum P levels are not always directly associated with luteal function [23]. Furthermore, we have assumed that this drawback does not affect our results due to our study is a randomized design, and the study involves a large number of cycles. On the other hand, we preferred not to overload the daily activity of our unit. Our results support that nowadays do not exist any robust evidence for the widespread use of progesterone as luteal phase support in mildly stimulated IUI cycles. The trend towards a higher clinical pregnancy rate in cycles supported with progesterone in all trials made up until now could explain that there may be a subgroup of cycles or patients which could benefit from this treatment, although to date that subgroup has not been identified yet. In conclusion, at the moment, on the basis that it is well documented that stimulated IVF cycles need LPS and due to the results of our study, progesterone supplementation should be administered only in those IUI cycles with a highly ovarian stimulation (more than one dominant follicle, or one dominant follicle plus several intermediate follicles), although we recognize the absence of robust evidence for this protocol. Further randomized trials with different subgroups are needed to establish which patients or IUI cycles can benefit from the use of progesterone in luteal phase.
Declaration of interest The authors report no conflicts of interest. The authors alone are responsible for the content and writing of this article.
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