Impact of progestin ovarian stimulation on newborn outcomes: a meta-analysis

Progestin-primed ovarian stimulation with letrozole using different doses of medroxyprogesterone acetate per day: a retrospective cohort study

Background

In the progestin-primed ovarian stimulation protocol, the oral administration of medroxyprogesterone acetate has been observed to effectively inhibit the LH surge during ovarian stimulation in patients experiencing infertility. Nevertheless, the use of utilizing medroxyprogesterone acetate during ovarian stimulation can result in more pronounced pituitary suppression, potentially necessitating increased doses of gonadotropins and extended treatment durations. Therefore, it is necessary to determine the optimal dose of medroxyprogesterone acetate, aiming to use relatively lower concentrations of medroxyprogesterone acetate to effectively and safely suppress early LH surges.

Method

This retrospective cohort study included 710 patients who underwent cycles of in vitro fertilization or intracytoplasmic sperm injection and were subjected the progestin-primed ovarian stimulation protocol utilizing letrozole between from 1st January 2021 to 31st December 2021. The study population was divided into low, medium, and high concentration groups based on the daily dosage of medroxyprogesterone acetate.The primary focus of this investigation was on the cumulative live birth rate. Secondary outcomes encompassed the occurrence of a premature surge in luteinizing hormone, the quantity of retrieved oocytes, viable embryos, and high-quality embryos, as well as clinical pregnancy rate, abortion rate, ectopic pregnancy rate, and multiple pregnancy rate.

Results

In this study, significant differences were observed among three groups in various parameters including body mass index, baseline levels of Anti-Müllerian hormone and luteinizing hormone, antral follicle count, total dose of gonadotropin, and duration of gonadotropin administration (p<0.05). The number of oocytes and viable embryos were significantly higher in medium group and higher than those in the low dose group. Following adjustments for confounding factors related to medroxyprogesterone acetate for various outcome measures, we conducted multiple regression analysis to investigate the independent effects of daily medroxyprogesterone acetate dosage within the combined progestin-primed ovarian stimulation and letrozole protocol. Following multivariable regression analysis, no disparities were found in embryo characteristics (number of oocytes retrieved, number of available embryos, number of high-quality embryos) or pregnancy outcomes (clinical pregnancy rate, cumulative live birth rate) among the three groups.

Conclusion

Progestin-primed ovarian stimulation with letrozole using different dose of medroxyprogesterone acetate per day was comparable in terms of the number of oocytes retrieved, the number of high-quality embryos, clinical pregnancy rate and cumulative live birth rate after frozen embryo transfer.

A randomized controlled trial to compare the live birth rate of the first frozen embryo transfer following the progestin-primed ovarian stimulation protocol vs. the antagonist protocol in women with an anticipated high ovarian response

OBJECTIVE

To compare the live birth rate of the first frozen embryo transfer (FET) after ovarian stimulation by the progestin-primed ovarian stimulation (PPOS) protocol vs. the antagonist protocol in women with an anticipated high ovarian response who were undergoing in vitro fertilization.

DESIGN

Randomized controlled trial.

SETTING

A tertiary assisted reproduction center.

PATIENTS

Women with infertility aged <43 years undergoing the first in vitro fertilization cycle and having antral follicle count of >15.

INTERVENTIONS

Medroxyprogesterone 10 mg daily was given from the start of ovarian stimulation until the day of ovulation trigger in the PPOS protocol. In the antagonist protocol, an antagonist 0.25 mg daily was given from the sixth day of ovarian stimulation until the day of ovulation trigger. Blinding was not possible for women or physicians but the biostatistician was blinded to the group assignment.

MAIN OUTCOME MEASURE

Live birth rate of the first FET cycle.

RESULTS

A total of 784 women were recruited from June 2020 and October 2021 and assigned randomly in a 1:1 ratio into two groups: PPOS group (n = 392) and antagonist group (n = 392). Embryo transfer was either cancelled or postponed in 62 women (62/392, 15.8%) in the PPOS group and 65 (65/392, 16.6%) in the antagonist group because of no transferable embryos or no FET within 6 months after randomization. The two groups were similar in demographic characteristics and the numbers of oocytes obtained or fertilized, cleaving embryos, good-quality embryos at day 3, blastocysts developed, and embryos or blastocysts frozen. There was no statistically significant difference in the live birth rate of the first FET cycle between the PPOS and antagonist groups on the basis of both the intention-to-treat analysis (37.5.0% [147/392] vs. 32.7% [128/392]; relative risk, 1.148 [95% confidence interval, 0.949-1.390]) and per-protocol analysis (44.5% [147/330] vs. 39.1% [128/327]; relative risk, 1.138 [95% confidence interval, 0.950-1.364]). Both groups showed comparable clinical pregnancy, ongoing pregnancy, miscarriage, multiple pregnancy, ectopic pregnancy, and cumulative live birth rates.

CONCLUSION

The live birth rates of the first FET following the PPOS and antagonist protocols were comparable in women with an anticipated high ovarian response.

CLINICAL TRIAL REGISTRATION NUMBER

NCT04414761 (ClinicalTrials.gov).

Comparing blastocyst euploid rates between the progestin-primed and gonadotrophin-releasing hormone antagonist protocols in aneuploidy genetic testing: a randomised trial protocol

INTRODUCTION

Progestin can inhibit the pituitary luteinising hormone (LH) surge during ovarian stimulation for in vitro fertilisation (IVF) and studies show progestin-primed ovarian stimulation (PPOS) is effective in blocking the LH surge in IVF. More and more centres are using PPOS because this regimen appears simpler and cheaper. This study aims to compare the euploidy rate of blastocysts following the PPOS protocol and the gonadotropin-releasing hormone antagonist protocol in women undergoing preimplantation genetic testing for aneuploidy (PGT-A).

METHODS/ANALYSIS

This is a randomised trial. A total of 400 women undergoing PGT-A will be enrolled and randomised according to a computer-generated randomisation list to either (1) the antagonist group: an antagonist given once daily from day 6 of ovarian stimulation till the day of the ovulation trigger; or (2) the PPOS group: dydrogesterone from the first day of ovarian stimulation till the day of ovulation trigger. The primary outcome is the euploidy rate of blastocysts.

ETHICS/DISSEMINATION

An ethical approval was granted from the ethics committee of assisted reproductive medicine in Shanghai JiAi Genetics and IVF institute (JIAIE2020-03). A written informed consent will be obtained from each woman before any study procedure is performed, according to good clinical practice. The results of this randomised trial will be disseminated in a peer-reviewed journal.

TRIAL REGISTRATION NUMBER

NCT04414748.

Progestin-primed ovarian stimulation: for whom, when and how?

Progestin-primed ovarian stimulation (PPOS) is being increasingly used for ovarian stimulation in assisted reproductive technology. Different progestins have been used with similar success. The available studies suggest a similar response to ovarian stimulation with gonadotrophin-releasing hormone (GnRH) analogues. Any differences in the duration of stimulation or gonadotrophin consumption are minor and clinically insignificant. PPOS has the advantage of oral administration and lower medication costs than GnRH analogues. As such it is clearly more cost-effective for fertility preservation and planned freeze-all cycles, but when fresh embryo transfer is intended PPOS can be less cost-effective depending on the local direct and indirect costs of the additional initial frozen embryo transfer cycle. Oocytes collected in PPOS cycles have similar developmental potential, including blastocyst euploidy rates. Frozen embryo transfer outcomes of PPOS and GnRH analogue cycles seem to be similar in terms of both ongoing pregnancy/live birth rates and obstetric and perinatal outcomes. While some studies have reported lower cumulative live birth rates with PPOS, they have methodological issues, including arbitrary definitions of the cumulative live birth rate. PPOS has been used in all patient types (except progesterone receptor-positive breast cancer patients) with consistent results and seems a patient friendly and cost-effective choice if a fresh embryo transfer is not intended.

The comparison between fixed versus degressive doses of medroxyprogesterone acetate combined with letrozole in patients of progestin-primed ovarian stimulation protocol: a propensity score-matched study

Objective

To explore the cycle characteristics and pregnancy outcomes of progestin-primed ovarian stimulation (PPOS) using fixed versus degressive doses of medroxyprogesterone acetate (MPA) in conjunction with letrozole (LE) in infertile women by propensity score matching (PSM) analysis.

Design

A retrospective cohort study.

Setting

Tertiary-care academic medical center.

Population

A total of 3173 infertile women undergoing their first in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) treatment within the period from January 2017 to December 2020.

Methods

A total of 1068 and 783 patients who underwent a fixed dose of MPA combined with LE and a degressive dose of MPA combined with LE protocols, respectively, were enrolled in this study. The freeze-all approach and later frozen-thawed embryo transfer (FET) were performed in both groups. Propensity score matching (1:1) was performed.

Main outcome measures

The primary outcomes were the dosage of MPA and the incidence of premature luteinizing hormone (LH) surges. The secondary outcomes were the number of oocytes retrieved, the cumulative live birth rate (CLBR) and the fetal malformation rate.

Results

We created a perfect match of 478 patients in each group. The dosage of MPA, the LH serum level on the eighth day of stimulation, progesterone (P) level and LH level on the hCG trigger day were significantly higher in the LE + fixed MPA group than in the LE + degressive MPA group (52.1 ± 13.1 mg vs. 44.9 ± 12.5 mg; 5.0 ± 2.7 IU/L vs. 3.7 ± 1.7 IU/L; 0.9 ± 0.5 ng/ml vs. 0.8 ± 0.5 ng/ml; 3.3 ± 2.4 IU/L vs. 2.8 ± 1.9 IU/L; P < 0.01). The duration of Gn, the number of follicles with diameter more than 16 mm on trigger day, the estradiol (E2) level on the hCG trigger day were lower in the LE + fixed MPA group than in the LE + degressive MPA group (9.7 ± 1.7 days vs. 10.3 ± 1.5 days; 5.6 ± 3.0 vs. 6.3 ± 3.0; 1752.5 ± 1120.8 pg/ml vs. 1997.2 ± 1108.5 pg/ml; P < 0.001). No significant difference was found in the incidence of premature LH surge, the number of oocytes retrieved, the number of top-quality embryos, clinical pregnancy rate (CPR), CLBR or fetal malformation rate between the two groups.

Conclusion

The combination of a degressive MPA dose with LE proved effective in reducing the total MPA dosage with comparable premature LH surge and pregnancy outcomes in women undergoing the PPOS protocol.

Role and effectiveness of progestins in pituitary suppression during ovarian stimulation for assisted reproductive technology: a systematic review and a meta-analysis

INTRODUCTION

Despite the many unknowns about its exact mechanism, progesterone and progestins are being successfully used to prevent luteinizing hormone (LH) surge during ovarian stimulation for assisted reproductive technology (ART). We will review progestin primed ovarian stimulation (PPOS) protocols in comparison with gonadotropin releasing hormone (GnRH) analogues and each other.

EVIDENCE ACQUISITION

MEDLINE via PubMed; Cochrane Central Register of Controlled Trials (CENTRAL); Scopus; Web of Science were screened with keywords related to assisted reproductive technology, ovarian stimulation progesterone, GnRH analogue and progesterone in several combinations. Search period was from the date of inception of each database until 20 May 2022.

EVIDENCE SYNTHESIS

Live birth or ongoing pregnancy rate per embryo transfer (ET) was similar in PPOS and GnRH antagonist cycles (RR=1.16, 95% CI: 0.93-1.44). Clinical pregnancy rate per ET was likewise similar (RR=1.12, 95% CI: 0.92-1.37). Miscarriage rate per pregnancy was similar with PPOS and GnRH antagonists in autologous cycles (RR=1.01, 95% CI: 0.65-1.55). Pooled analyses showed similar live birth rate between progestins and short GnRH agonist protocols (RR=1.01, 95% CI: 0.49-2.09), however, clinical pregnancy rates per ET were significantly higher with progestins (RR=1.31, 95% CI: 1.06-1.62). Miscarriage rate per pregnancy was similar with progestins (RR=0.82, 95% CI: 0.55-1.21).

CONCLUSIONS

Progestins seem to be an efficient option for pituitary suppression during ovarian suppression, providing similar outcomes for stimulation and pregnancy. They can be especially beneficial for women for whom fresh ET is not considered.

Comparison of Cumulative Live Birth Rates between Flexible and Conventional Progestin-Primed Ovarian Stimulation Protocol in Poor Ovarian Response Patients According to POSEIDON Criteria: A Cohort Study

RESEARCH QUESTION

To compare the cumulative live birth rate (CLBR) per oocyte retrieval cycle of a conventional progestin-primed ovarian stimulation (cPPOS) regimen with a flexible progestin-primed ovarian stimulation (fPPOS) regimen in poor ovarian response patients, according to POSEIDON criteria.

DESIGN

Poor ovarian response women, according to POSEIDON criteria, who underwent the first PPOS protocol for in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) between January 2018 and December 2020 were included. The fPPOS group involved 113 participants, and the cPPOS group included 1119 participants. In the cPPOS group, medroxyprogesterone acetate (MPA) (10 mg/d) was administrated on the gonadotropin injection the same day as gonadotropin injections in the cPPOS group, while MPA was started either on the day when the leading follicle with mean diameter > 12mm was present and/or serum E2 was >300 pg/mL in the fPPOS protocol group. The primary outcome was CLBR.

RESULTS

The fPPOS protocol had higher CLBR per oocyte retrieval cycle compared to the cPPOS group, even without a statistically significant difference (29.6% vs. 24.9%, p = 0.365). The fPPOS group had fewer numbers of retrieved oocytes (2.87 ± 2.03 vs. 3.76 ± 2.32, p < 0.001) but a higher MII oocyte rate (89.8% vs. 84.7%, p = 0.016). In addition, the number of available embryos in the two groups was comparable (1.37 ± 1.24 vs. 1.63 ± 1.38, p = 0.095). There were five women in the fPPOS group, and 86 women in the cPPOS group had a premature LH surge (4.2% vs. 6.8%, p = 0.261). In the fPPOS group, there was one instance of premature ovulation, while in the cPPOS group, there were six occurrences of premature ovulation (0.8 vs. 0.5%, p = 1.000).

CONCLUSION(S)

The novel fPPOS protocol appears to achieve higher CLBR even without significant differences and with MPA consumption compared with cPPOS protocol in low-prognosis patients.

Medroxyprogesterone acetate: an alternative to GnRH-antagonist in oocyte vitrification for social fertility preservation and preimplantation genetic testing for aneuploidy

RESEARCH QUESTION

Can medroxyprogesterone acetate (MPA) be used as a pituitary suppressor instead of a gonadotrophin releasing hormone (GnRH) antagonist during ovarian stimulation in elective fertility preservation and preimplantation genetic testing for aneuploidy (PGT-A) cycles?

DESIGN

A multicentre, retrospective, observational, cohort study conducted in 11 IVIRMA centres affiliated to private universities. Of a total of 1652 cycles of social fertility preservation, 267 patients were stimulated using a progestin-primed ovarian stimulation protocol (PPOS), and 1385 patients received a GnRH antagonist. In the PGT-A cycles, 5661 treatments were analysed: 635 patients received MPA and 5026 patients received GnRH antagonist. A further 66 fertility preservation and 1299 PGT-A cycles were cancelled. All cycles took place between June 2019 and December 2021.

RESULTS

In the social fertility preservation cycles, the number of mature oocytes vitrified in MPA was similar to the number of those treated with an antagonist, a trend that was seen regardless of age (≤35 or >35 years). In the PGT-A cycles, no differences were found in number of metaphase II, two pronuclei, number of biopsied embryos (4.4 ± 3.1 versus 4.5 ± 3.1), rate of euploidy (57.9% versus 56.4%) or ongoing pregnancy rate (50.4% versus 47.1%, P = 0.119) between the group receiving MPA versus a GnRH antagonist, whereas the clinical miscarriage rate was higher in the antagonist group (10.4% versus 14.8%, P = 0.019).

CONCLUSIONS

Administration of PPOS yields similar results to GnRH antagonists in oocytes retrieved, rate of euploid embryos and clinical outcome. Hence, PPOS can be recommended for ovarian stimulation in social fertility preservation and PGT-A cycles, as it allows greater patient comfort.

Double stimulation for the management of poor-prognosis patients: where are we going?

PURPOSE OF REVIEW

The technical improvements in IVF allowed the implementation of nonconventional ovarian stimulation protocols for some specific patients. Where time is crucial, such as with oncologic patients, poor-prognosis patients, patients with low ovarian reserve, and those with advanced maternal age, access to IVF treatment is even more critical. Some of these protocols might start in the late follicular phase, luteal phase, or involve both stimulations within the same ovarian cycle.

RECENT FINDINGS

Until now, published evidence showed that oocytes retrieved from unconventional protocol seem to be developmentally, genetically, and reproductively competent. Second stimulation in the same ovarian cycle after the conventional approach may represent a sound alternative to oocyte accumulation. This can be proposed in progress after careful counselling focused on the patients' chances of finding at least one euploid embryo on account of their age and of the number of blastocysts obtained after the conventional approach.

SUMMARY

The adoption of these new strategies, known as double stimulation protocol, can be conceived as a real full-personalization of ovarian stimulation. Multicentre prospective RCTs are urgently needed to evaluate the efficacy, efficiency, and costs of double stimulation versus two consecutive conventional approaches with standard or mild stimulation and in a different IVF setting.

Ovarian Stimulation with FSH Alone versus FSH plus a GnRH Antagonist for Elective Freezing in an Oocyte Donor/Recipient Programme: A Protocol for a Pilot Multicenter Observational Study

Preliminary data have shown that it is possible to attempt in vitro fertilization (IVF) treatment in fresh cycles without the use of a gonadotropin-releasing hormone (GnRH) antagonist or any other medication to prevent the luteinizing hormone (LH) surge during ovarian stimulation. To date, there is no information on this topic in the context of a prospective controlled trial. However, as prevention of the LH surge is an established procedure in fresh cycles, the question is whether such a study can be performed in frozen cycles. We aim to perform a pilot study in order to compare the efficacy of a protocol using FSH alone with that of a protocol using follicle-stimulating hormone (FSH) plus a GnRH antagonist for controlled ovarian hyperstimulation (COH) in cycles of elective freezing in the context of a donor/recipient program. This is a seven-center, two-arm prospective pilot cohort study conducted at the respective Assisted Reproductive Units in Greece. The hypothesis to be tested is that an ovarian stimulation protocol that includes FSH alone without any LH surge prevention regimens is not inferior to a protocol including FSH plus a GnRH antagonist in terms of the clinical outcome in a donor/recipient model. The results of the present study are expected to show whether the addition of the GnRH antagonist is necessary in terms of the frequency of LH secretory peaks and progesterone elevations >1 ng/mL during the administration of the GnRH antagonist according to the adopted frequency of blood sampling in all Units.

Neonatal outcomes and congenital malformations in children born after progestin-primed ovarian stimulation protocol

Purpose

The purpose of this study is to assess the safety of progestin-primed ovarian stimulation (PPOS) protocol regarding the neonatal outcomes and congenital malformations in babies born after in vitro fertilization (IVF) and frozen embryo transfer (FET).

Methods

In this large retrospective cohort study, a total of 16,493 infants born between 1 September 2013 and 31 July 2021 from IVF and FET cycles after treatment with either PPOS (n = 15,245) or gonadotropin-releasing hormone antagonist (GnRH-ant) (n = 1,248) were finally enrolled. The primary outcome measure was the incidence of congenital malformations. The secondary outcome measures were rates of low birth weight (LBW), very low birth weight (VLBW), preterm birth (PTB), very preterm birth (VPTB), and early neonatal death.

Results

Birth characteristics for both singletons and twins regarding the sex of infants, gestational age, birth weight, and birth length were comparable between the PPOS group and the GnRH-ant group. Rates of LBW, VLBW, PTB, VPTB, and early neonatal death were also similar. The reanalysis using propensity score matching (PSM) and multivariable logistic regression indicated that the PPOS protocol could not increase the risk of adverse neonatal outcomes compared with the GnRH-ant protocol. Furthermore, no significant difference was observed in the overall incidence of congenital malformations in live-born babies. After PSM and controlling for all confounders, the results remained insignificant with an adjusted odds ratio of 0.66 [95% confidence interval (CI) 0.32-1.34] and 2.43 [95% CI 0.97-6.06], respectively, for singletons and twins.

Conclusions

Our study suggests that compared with GnRH-ant treatment for IVF, the PPOS protocol could not produce a negative effect on the newborn population in terms of neonatal outcomes and congenital malformations.

Comparing progesterone primed ovarian stimulation (PPOS) to GnRH antagonist protocol in oocyte donation cycles

Background:

Progesterone-primed ovarian stimulation (PPOS) protocol is based on the principle of preventing pre-mature luteinising hormone surge during ovarian stimulation using progesterone.

Aims:

In this study, we aimed to compare the cost-effectiveness of PPOS over GnRH antagonist cycles in oocyte donor cycles where freeze all is a norm.

Settings and Design:

It is a prospective cohort study with 130 participants.

Materials and Methods:

We included all women undergoing oocyte donation using PPOS protocol and antagonist protocol at our centre. Fifty-seven belonged to the PPOS group and were given medroxyprogesterone acetate (MPA) and 73 belonged to the GnRH antagonist group who received cetrorelix. The primary outcome was the number of mature oocyte retrieved at OPU and the cost involved per stimulation cycle.

Statistical Analysis Used:

For normally distributed observations, we used t-test, and for the variables of non-normal distribution, Mann–Whitney U-test was used. The significance was accepted for P < 0.05.

Results:

The baseline clinical characteristics of the donors were comparable with a mean age of 25.42 ± 2.90 years, body mass index of 24.00 ± 4.00 kg/m² and antral follicle count of 18.63 ± 5.23. The duration of stimulation was similar in both the groups as well as the total gonadotropin dose required was not significantly different. The number of mature oocytes retrieved was same in both the groups (10.41 ± 4.04 with antagonist and 10.25 ± 3.23 with PPOS, P = 0.964). There were no reported cases of severe ovarian hyperstimulation syndrome (OHSS) in any of the groups. The incidence of mild-to-moderate OHSS in the antagonist group was 5.4% and in the PPOS group was 3.6%, and the difference was not significant (P = 0.69). The cost per mature oocyte (M2) was significantly higher in the antagonist protocol in comparison to the PPOS protocol (INR 9485.69 ± 5751.11 vs. Rs. 5945.86 ± 2848.59, respectively, P < 0.001).

Conclusion:

Our study identifies PPOS protocol using MPA to be more cost-effective and patient-friendly than conventional GnRH antagonist protocol in oocyte donor cycles.

Progestin-Primed Ovarian Stimulation Protocol for Patients in Assisted Reproductive Technology: A Meta-Analysis of Randomized Controlled Trials

Objectives

Progestin-primed ovarian stimulation (PPOS) is a new ovarian stimulation protocol that can block the luteinizing hormone (LH) surge through progesterone instead of traditional down regulating or gonadotropin-releasing hormone (GnRH) antagonist, and in order to achieve multi-follicle recruitment. This paper aims to investigate the effectiveness of PPOS and its suitability for infertile patients with different ovarian reserve functions.

Methods

We searched published randomized controlled trials (RCTs) about PPOS on Cochrane Library, PubMed, Embase, and Web of Science. The search period spanned from January 1, 2015 to November 16, 2020. The data were extracted, and the meta-analysis was performed on ovarian stimulation as well as embryological and clinical outcomes. The outcomes were pooled by a random effects model, and the risk of heterogeneity was evaluated. Subgroup analysis was performed for different ovarian reserve patients.

Results

The clinical pregnancy rates and live birth or ongoing pregnancy rates with the PPOS protocol were not different from those with the control group. In the diminished ovarian reserve (DOR) subgroup, the PPOS protocol had a lower rate of premature LH surge [RR = 0.03, 95% CI = 0.01 to 0.13, p < 0.001]. The PPOS protocol had a lower rate of ovarian hyperstimulation syndrome (OHSS) [RR = 0.52, 95% CI = 0.36 to 0.76, p < 0.001, I2 = 0.00%]. The secondary outcomes showed that the number of oocytes retrieved, MII oocytes, and viable embryos was higher than that of the control protocol in DOR patients [(MD = 0.33, 95% CI = 0.30 to 0.36, p < 0.001), (MD = 0.30, 95% CI = 0.27 to 0.33, p < 0.001), (MD = 0.21, 95% CI = 0.18 to 0.24, p < 0.001)] and normal ovarian reserve (NOR) patients [(MD = 1.41, 95% CI = 0.03 to 2.78, p < 0.001), (MD = 1.19, 95% CI = 0.04 to 2.35, p < 0.001), (MD = 1.01, 95% CI = 0.21 to 1.81, p = 0.01)].

Conclusion

The findings suggest that PPOS is an effective ovarian stimulation protocol and is beneficial for patients with different ovarian reserve functions, which needs to be validated in more RCTs with larger samples.

ART outcomes following ovarian stimulation in the luteal phase:a systematic review and meta-analysis

PURPOSE

This study aimed to evaluate the impact of luteal phase ovarian stimulation (LPS) on the outcomes of assisted reproductive technology (ART) for infertile couples and patients desiring non-urgent egg cryopreservation.

METHODS

We included all studies reported patients who received LPS and that used follicular phase ovarian stimulation (FPS) as a comparison group until January 2021. Prior meta-analysis regarding the outcomes of LPS in double stimulation and fertility preservation have already been published, so these studies were excluded. Risk of Bias in Non-randomized Studies of Interventions was used to assess the study quality. The study was registered in the International Prospective Register of Systematic Reviews database (CRD42020183946).

RESULTS

Twelve studies with a total of 4433 patients were included. The regimen employed can be categorized into two groups, but there is currently no evidence to support one over the other. After we excluded the largest study, the clinical pregnancy rate and live birth rate were similar after FPS and LPS. There were significantly more stimulation days and total gonadotropins used in the LPS group. After subgroup analysis, we found that poor responders received significantly more cumulus oocyte complexes (+0.64) in the LPS group.

CONCLUSION

Current evidence indicates that patients in the LPS group could achieve pregnancy outcomes non-inferior to those in the FPS group. Because of current debate over freeze-all policy and the limited data about live birth rate, the universal use of LPS is considered controversial. In the future, more well-designed studies are necessary to investigate the indications for LPS and its cost-effectiveness.

Medroxyprogesterone acetate is a useful alternative to a gonadotropin-releasing hormone antagonist in oocyte donation: a randomized, controlled trial

OBJECTIVE

To compare ovarian response and reproductive outcomes in oocyte donors undergoing pituitary suppression with medroxyprogesterone acetate (MPA) versus those undergoing conventional treatment with a gonadotropin-releasing hormone (GnRH) antagonist.

DESIGN

A prospective, randomized, controlled trial of cycles was conducted from October 2017 to June 2019 to evaluate ovarian response in terms of the number of oocytes. The reproductive outcomes of the recipients were retrospectively analyzed later.

SETTING

A university-affiliated private in vitro fertilization center.

PATIENT(S)

We randomly divided 318 donors into 2 groups in a 1:1 ratio. The oocytes obtained were assigned to 364 recipients. One hundred sixty-one donors were treated with a daily dose of 10 mg of MPA administered orally from the beginning of ovarian stimulation (OS), and 156 were treated with a GnRH antagonist (initiated once the leading follicle reached a diameter of 13 mm). Transvaginal ultrasound was performed, and serum estradiol, luteinizing hormone, and progesterone levels were recorded during monitoring. The following additional parameters were analyzed: endocrine profile (in follicular fluid), number of metaphase II oocytes, and pregnancy outcome.

INTERVENTION(S)

The donors included in the study group were stimulated using recombinant follicle-stimulating hormone and MPA at 10 mg/day, simultaneously begun on cycle day 2 or 3. Ovulation was induced using a GnRH agonist when dominant follicles matured. A short protocol with ganirelix at 0.25 mg/day was used for the control group. Oocytes were assigned to the recipients, followed by routine in vitro fertilization procedures in which 1 embryo was usually transferred.

MAIN OUTCOME MEASURE(S)

The primary outcome measure was the numbers of oocytes and metaphase II oocytes retrieved. The secondary outcomes were the incidence of premature luteinizing hormone surge, serum and follicular fluid hormone profiles, and clinical pregnancy outcomes in the recipient group.

RESULT(S)

The number of oocytes retrieved was 21.4 ± 11.7 in the MPA group and 21.2 ± 9.2 in the antagonist group (mean difference 0.14; 95% confidence interval -2.233, 2.517). The total dose of recombinant follicle-stimulating hormone, duration of OS, and endocrine profiles of the serum and follicular fluids were comparable in the 2 groups. No early ovulation was observed in either group. No statistically significant differences with respect to implantation rate (68.1% in the MPA group vs. 62% in the antagonist group), clinical pregnancy rate (64.5% in the MPA group vs. 57.8 in the antagonist group), ongoing pregnancy rate (55.4% in the MPA group vs. 48.5% in the antagonist group), live birth rate (55.1% in the MPA group vs. 48.5% in the antagonist group), or cumulative live birth rate (73.8% in the MPA group vs. 70.7% in the antagonist group) were observed between the groups.

CONCLUSION(S)

The administration of MPA resulted in oocyte retrieval rates, endocrine profiles, viable embryo numbers, and pregnancy outcomes similar to those achieved with the GnRH antagonist. Therefore, MPA can be recommended for OS in oocyte donation because it permits a more patient-friendly approach.

CLINICAL TRIAL REGISTRATION NUMBER

NCT03300960.

Preconception ambient temperature and preterm birth: a time-series study in rural Henan, China

Changes in the preconception ambient temperature (PAT) can affect the gametogenesis, disturbing the development of the embryo, but the health risks of PAT on the developing fetus are still unclear. Here, based on the National Free Preconception Health Examination Project in the rural areas of Henan Province, we evaluate the effects of PAT on preterm birth (PTB). Data of 1,231,715 records from self-reported interviews, preconception physical examination, early gestation follow-up, and postpartum follow-up were collected from 1 January 2013 to 31 December 2016. Generalized additive models were used to assess the cumulative and lag effects of PAT upon PTB. The significant cumulative effects of mean temperature within 2 weeks and 3 weeks on the risk of PTB, especially upon late PTB (34-36 weeks) (P < 0.05), were observed. Exposure to extreme heat (> 90th percentile) within 2 weeks (RR = 1.470) and 3 weeks (RR = 1.375) before conception could increase the risk of PTB. After stratifying PTB, exposure to extreme heat within 2 weeks before conception can increase the risks of early (< 34 weeks) and late PTB (P < 0.05). Besides, exposure to extreme cold (< 10th percentile) within 3 weeks or longer before conception can elevate the risk of PTB, especially late PTB. The significant lag effects of temperature changes on the risk of early PTB (lag-8 days or earlier) were observed. In conclusion, the risk of PTB was susceptible to PAT changes within 2 weeks or longer before conception. Our findings provide (i) guidance for rural couples to make pregnancy plans and (ii) scientific evidence for the government to formulate policies to prevent PTB.

Exogenous progesterone for LH surge prevention is redundant in ovarian stimulation protocols

During ovarian stimulation for IVF-embryo transfer treatment, a premature LH surge may lead to progesterone elevation that disrupts endometrial maturation and affects the probability of pregnancy following fresh embryo transfer. Preventing this LH surge and progesterone elevation using gonadotrophin-releasing hormone (GnRH) analogues is considered a standard practice. The same policy applies to cycles in which the 'freeze-all' protocol has been selected from the outset (e.g. donors), but the need for this has not been discussed. Moreover, in 'freeze-all' cycles, exogenous progesterone administration tends to replace GnRH antagonists, without reducing efficacy after embryo transfer in frozen-thawed cycles. Nevertheless, as exogenous progesterone is expected to have the same impact on the endometrium as endogenous progesterone, it is clear that, unlike in fresh cycles, in 'freeze-all' cycles an endogenous LH surge prevention does not seem necessary. Therefore, both GnRH antagonists and exogenous progesterone appear to be redundant in 'freeze-all' cycles, and in this context the indications for the use of GnRH analogues in ovarian stimulation protocols need to be revisited.

Progestins for pituitary suppression during ovarian stimulation for ART: a comprehensive and systematic review including meta-analyses

BACKGROUND

Progestins are capable of suppressing endogenous LH secretion from the pituitary. Progestins can be used orally and are less expensive than GnRH analogues. However, early endometrial exposure to progestin precludes a fresh embryo transfer (ET), but the advent of vitrification and increasing number of oocyte cryopreservation cycles allow more opportunities for using progestins for pituitary suppression.

OBJECTIVE AND RATIONALE

This review summarizes: the mechanism of pituitary suppression by progestins; the effectiveness of progestins when compared with GnRH analogues and with each other; the effect of progestins on oocyte and embryo developmental potential and euploidy status; and the cost-effectiveness aspects of progestin primed stimulation. Future research priorities are also identified.

SEARCH METHODS

The Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE via PubMed, the Web of Science and Scopus were screened with a combination of keywords related to ART, progesterone, GnRH analogue and ovarian stimulation, in various combinations. The search period was from the date of inception of each database until 1 April 2020. Only full text papers published in English were included.

OUTCOMES

Overall, the duration of stimulation, gonadotrophin consumption and oocyte yield were similar with progestins and GnRH analogues. However, sensitivity analyses suggested that progestins were associated with significantly lower gonadotrophin consumption than the long GnRH agonist protocol (mean difference (MD) = -648, 95% CI = -746 to -550 IU) and significantly higher gonadotrophin consumption than the short GnRH agonist protocol (MD = 433, 95% CI = 311 to 555 IU). Overall, live birth, ongoing and clinical pregnancy rates per ET were similar with progestins and GnRH analogues. However, when progestins were compared with GnRH agonists, sensitivity analyses including women with polycystic ovary syndrome (risk ratio (RR) = 1.27, 95% CI = 1.06 to 1.53) and short GnRH agonist protocols (RR = 1.14, 95% CI = 1.02 to 1.28) showed significantly higher clinical pregnancy rates with progestins. However, the quality of evidence is low. Studies comparing medroxyprogesterone acetate, dydrogesterone and micronized progesterone suggested similar ovarian response and pregnancy outcomes. The euploidy status of embryos from progestin primed cycles was similar to that of embryos from conventional stimulation cycles. Available information is reassuring regarding obstetric and neonatal outcomes with the use of progestins. Despite the lower cost of progestins than GnRH analogues, the mandatory cryopreservation of all embryos followed by a deferred transfer may increase cost per live birth with progestins as compared to an ART cycle culminating in a fresh ET.

WIDER IMPLICATIONS

Progestins can present an effective option for women who do not contemplate a fresh ET, e.g. fertility preservation, anticipated hyper responders, preimplantation genetic testing, oocyte donors, double stimulation cycles.