The effect of progesterone supplementation for luteal phase support in natural cycle frozen embryo transfer: a systematic review and meta-analysis based on randomized controlled trials

Comparison of Luteal Support Protocols in Frozen IVF/ICSI Cycles: A Network Meta-Analysis

BACKGROUND

Luteal support is a core success factor of frozen embryo transfers (FET). However, inconsistency across recommended protocols generates notable heterogeneity across reproductive outcomes.

OBJECTIVE

To determine the most effective luteal support strategy (LPS) based on five key factors related to the effectiveness of FET cycles.

SEARCH STRATEGY

Twelve databases and two prospective registers were searched from inception to 1st January 2024. The study was prospectively registered under the PROSPERO database (CRD42024513549).

SELECTION CRITERIA

Randomised Controlled Trials (RCTs) and observational studies of women undergoing frozen embryo transfers were included.

DATA COLLECTION AND ANALYSIS

Bayesian network meta-analysis (NMA) model presenting random effects, risk ratios (RRs) with 95% credibility intervals (CrIs) was employed. Primary outcomes included clinical pregnancy, live birth, and miscarriage. Secondary outcomes included biochemical pregnancy and multiple pregnancy events.

MAIN RESULTS

Fourteen studies, of which eight RCTs, comparing 12 interventions upon 4688 participants, were included. Overall, CiNeMa risk of bias was moderate, and network inconsistency per outcome was low. Thirteen studies reported on clinical pregnancy events with vaginal progesterone (VP) and a single or double dose of subcutaneous GnRH agonist (GnRHa), significantly improving clinical pregnancy, RR 1.86 [95% CrI 1.18, 2.93].

CONCLUSIONS

The addition of 0.1 mg subcutaneous GnRH agonist in a single (Day 3 post ET) or double (Day 3 and Day 6 post ET) schema upon a vaginal progesterone regimen till Week 12 appears to improve clinical pregnancy events in FET cycles.

Progesterone Luteal Support in Natural Cycles for Unexplained Infertility: A Randomised Controlled Trial (The PiNC Trial)

OBJECTIVE

To compare the effect of luteal-phase progesterone supplementation in natural cycles to expectant management on live birth rates in women with unexplained infertility (UI).

DESIGN

An open-label, parallel-arm, single-centre randomised controlled trial.

SETTING

One tertiary NHS-funded fertility unit.

POPULATION

Couples with UI for at least 1 year.

METHOD

A comparison of luteal phase micronised vaginal progesterone treatment (400 mg bd) with timed intercourse and timed intercourse alone for 3 cycles.

MAIN OUTCOME MEASURES

Primary outcome: Livebirth rate.

SECONDARY OUTCOMES

Biochemical pregnancy, clinical pregnancy, mid-luteal serum progesterone and pregnancy loss.

RESULTS

One hundred and forty-three couples were randomised. Livebirth rates were 11/72 (15.3%) in the treatment group versus 5/71 (7.0%) in the control group (RR 2.17, 95% CI 0.79-5.93). Biochemical pregnancy rates were 15/72 (20.8%) versus 10/71 (14.1%), (RR 1.48, 95% CI 0.72-3.07) and clinical pregnancy rates were 14/72 (19.4%) versus 9/71 (12.7%), (RR 1.53, 95% CI 0.71-3.31) in the treatment and control groups respectively. Pregnancy losses: 4/15 treatment group versus 5/10 control group (RR 0.53, 95% CI 0.19-1.51). One biochemical pregnancy loss in each group and 2/15 miscarriages in the treatment group versus 3/10 in the control group. Total miscarriage rates including biochemical losses were 3/15 (20%) versus 4/10 (40%) (RR 0.5, 95% CI 0.14-1.77).

CONCLUSIONS

The results did not reach statistical significance. However, the difference in livebirth rates warrants further investigation as this simple, noninvasive, inexpensive treatment would be a very attractive option for affected couples. A larger trial using the effect size from this study to guide sample size is planned.

TRAIL REGISTRATION

The PiNC trial was registered with the EU Clinical Trials Register on 29/11/2019 www.clinicaltrialsregister.eu/ctr-search/search?query=homerton. The first participant was recruited on 25/2/2020.

Impact of follicle size before luteal progesterone supplementation on clinical outcomes of modified natural cycle single frozen embryo transfer

Objective

To determine whether follicle size at midcycle transvaginal sonography imaging before luteal progesterone supplementation predicts modified natural cycle single frozen embryo transfer (mNC-SFET) outcomes.

Design

Retrospective chart review.

Subjects

Frozen embryo transfer charts were reviewed. After inclusion and exclusion criteria were applied, data were abstracted from cases of mNC-SFET (n = 115).

Exposure

For group A, lead follicle measuring <16 mm on day of trigger or peak +ovulation predictor kit (n = 50), and for group B, lead follicle measuring ≥16 mm on day of trigger or peak +ovulation predictor kit (n = 65).

Main Outcome Measures

Follicle size analyzed as possible predictor of primary outcome ongoing pregnancy rate (OPR) as well as secondary outcomes implantation rate (IR), clinical pregnancy rate (CPR), and spontaneous abortion (SAB) rate via bivariate associations and multivariate logistic regression analyses.

Results

Bivariate analyses showed no differences between groups in OPR (A, 48.0%, 24/50, and B, 44.6 %, 29/65), IR (A, 64.0%, 32/50, and B, 61.5%, 40/65), CPR (A, 58.0%, 29/50, and B, 52.3%, 34/65), and SAB rates (A, 25.0%, 8/32, and B, 27.5%, 11/40). Multivariate analysis to investigate potential confounding between lead follicle size and outcomes of interest showed no difference in the primary and secondary outcomes. Furthermore, multivariate analyses using lead follicle size as a continuous variable showed no difference in outcomes.

Conclusion

In normo-ovulatory women undergoing mNC-SFET with natural endometrial preparation with human chorionic gonadotropin trigger or luteinizing hormone surge to time frozen embryo transfer, lead follicle size before luteal phase supplementation does not impact clinical outcomes such as IR, CPR, SAB rate, or OPR.

Re-embarking in ART while still breastfeeding: an unresolved question

Infertile women may request to embark on a new course of Assisted Reproductive Technologies (ART) in pursuit of a second child while still breastfeeding their first child. Breastfeeding is a time of profound hormonal changes that may interfere with ovarian physiology and uterine receptivity. Prolactin and oxytocin can mediate a plethora of potential detrimental effects. However, robust evidence to advise in favor or against ART during breastfeeding is lacking. In this narrative review, we reviewed the literature with the intent to shed light on this neglected issue. Possible adverse effects on ART success emerged for ovulatory mechanisms, folliculogenesis, uterine contractions, uterine peristalsis, and early embryo development. A negative impact of exogeneous hormones on infant health might be considered only for stimulation cycles. Overall, most concerns can be claimed for the clinical setting of ovarian stimulation, followed by the one of embryo transfer in a natural cycle and, finally, by the embryo transfer in a hormone replacement treatment preparation. However, in general, it seems wise to wait for breastfeeding to be discontinue before re-embarking on IVF, also considering that a too short interpregnancy interval may be deleterious to pregnancy outcomes. On the other hand, one must also recognize that available evidence is insufficient to deny access to treatments for women requesting earlier access. These women must be informed regarding the non-fully reassuring evidence.

Exogenous progesterone rescue in patients with low mid-luteal serum progesterone levels undergoing true natural vitrified-warmed blastocyst transfer

PURPOSE

To explore whether a 25 mg subcutaneous progesterone daily rescue daily improves the reproductive outcomes in patients with low serum progesterone (P4) levels (7-10 ng/mL), measured one day before true natural cycle (t-NC) frozen embryo transfer (FET).

METHODS

A cohort study of 192 women undergoing t-NC warmed blastocyst transfer. Patients were stratified into three different groups based on serum P4 levels on the FET-1 day: patients who had serum P4 levels of 7-10 ng/mL and underwent rescue progesterone administration (rescue group), patients with serum P4 levels of 7-10 ng/mL without progesterone administration (non-rescue group), and patients with serum P4 > 10 ng/mL on FET-1 day (control group). The primary outcome was possible differences in live birth rate (LBR) between groups.

RESULTS

The LBRs for the serum P4 7-10 ng/mL without rescue, 7-10 ng/mL with rescue, and > 10 ng/mL (control) groups were 41%, 46%, and 52%, respectively (p = 0.61). The estimated adjusted probability of live birth for serum P4 7-10 ng/mL without rescue, 7-10 ng/mL with rescue, and > 10 ng/mL (control) groups were also comparable: 43.5% (95% CI, 20.0-70.4%), 49.8% (95% CI, 28.1-71.6%), and 57.4% (95% CI, 44.0-69.8%), respectively.

CONCLUSION

Serum P4 levels higher than 7 ng/mL seem to secure LBRs in patients undergoing t-NC FET. A rescue policy consisting of a daily subcutaneous 25 mg progesterone dose in patients with serum P4 levels 7-10 ng/mL does not further enhance LBRs when compared to those patients with similar serum P4 levels without rescue.

Use of oral allylestrenol in women with recurrent spontaneous abortion: A retrospective clinical trial

Recurrent spontaneous abortion (RSA), defined as two or more clinically confirmed pregnancies that end before 20-24 weeks of gestation, encompasses both embryonic and fetal losses and is a significant clinical challenge. The aim of this study was to compare the efficacy of allylestrenol (AT) and progesterone in improving pregnancy outcomes in RSA. From June 2021 to June 2024, 480 participants were randomly assigned to an AT, Progesterone, or Control group. Key outcomes included early pregnancy rates, ongoing pregnancies with fetal heart activity, live birth rates after 24 weeks, and pregnancy loss before 24 weeks. Results indicated significantly higher pregnancy rates at 6-8 weeks in both the Allylestrenol (71.8%) and Progesterone groups (76.2%) compared to the Control group (57.5%). At 12 weeks, ongoing pregnancies with fetal heart activity were higher in the Allylestrenol (65%) and Progesterone groups (64%) versus the Control group (52.5%). Both treatment groups had higher live birth rates (60% and 60.6%) compared to the Control group (45%). Pregnancy loss before 24 weeks was lower in both treatment groups (31.8% and 33.1%) compared to the Control group (38.7%). No significant adverse reactions were observed, indicating good safety profiles for both treatments. These findings suggest that both treatments effectively improve pregnancy outcomes in cases of RSA with satisfactory safety, supporting their potential clinical use. However, further research is needed to explore their long-term effects and broader applicability in clinical settings.

Progesterone-modified natural cycle preparation for frozen embryo transfer

RESEARCH QUESTION

Is there any difference in clinical outcomes between the progesterone-modified natural cycle (P4mNC) and hormone replacement therapy (HRT) endometrial preparation protocols after single euploid blastocyst frozen embryo transfer (FET) cycles?

DESIGN

A retrospective cohort study was performed at a single, private, high-volume fertility centre. Patients who underwent single euploid blastocyst FET between January 2017 and December 2019 were included. A total of 1933 FET cycles were reviewed, and 723 FET cycles from 548 patients met the inclusion criteria. Two groups were compared according to endometrial preparation: 327 P4mNC-FET and 396 HRT-FET cycles. The primary outcome was the live birth rate. The secondary outcomes included the clinical pregnancy rate and the miscarriage rate.

RESULTS

There were no differences in the clinical pregnancy rate (50.2% versus 47.0%, P = 0.688), miscarriage rate (9.8% versus 14.5%, P = 0.115) and live birth rate (45.0% versus 39.6%, P = 0.331) between the P4mNC-FET and HRT-FET groups after covariate adjustments.

CONCLUSIONS

There were no differences in the clinical outcomes between the P4mNC-FET and HRT-FET cycles. These results indicate that P4mNC-FET cycles produce clinical outcomes comparable to those of more traditional HRT-FET while allowing greater flexibility in the timing of embryo transfer.

Low Dose hCG Support in Modified Natural Frozen Embryo Transfer Cycles

What is the effect of a single low-dose recombinant hCG injection after embryo transfer (ET) in letrozole-induced modified natural frozen embryo transfer cycles (mNC-FET)?. An observational study was conducted in the university-affiliated referral clinic between 2022 and 2024. Women aged 18-42 with at least one vitrified blastocyst obtained from the previous cycle(s) were included. Ovulation induction for endometrial preparation was initiated with oral letrozol (5 mg/day) for five days. Ovulation was triggered using 6500 IU rec hCG sc when the leading follicle > 17 mm, endometrial thickness > 7.5 mm, and serum progesterone (P) < 1.5 ng/ml. All women received 30 mg dydrogesterone/day po for additional five-day luteal support. On the 6th day, ET was performed. Based on a quasi-randomized design, a group of women additionally received a half single bolus of (3250 IU) rec hCG (sc) on the morning of 3rd day of ET (hCG group). Women who did not receive additional hCG were assigned as controls. One hundred fifty-four women were detected to be eligible for the study among 2150 initiated FET cycles during the period. Demographic data of the groups, including mean women's age, BMI, serum AMH, and infertility etiologies, were comparable in terms of variables. Mean serum progesterone values and the number of transferred embryos were also similar. A significantly higher ongoing pregnancy/started cycle was documented in the hCG group than in controls (46.7% vs 33.6% respectively, p = 0.03*). A single low-dose hCG injection after ET may improve the OPRs of women in letrozole mNC-FET cycles.

The natural menstrual cycle revisited - can natural cycle be trusted

BACKGROUND

The serum progesterone (P4) level during the luteal phase (LP) plays a crucial role in the initiation and maintenance of pregnancy. However, it is unclear whether the natural cycle consistently provides the best endocrine profile and whether mid-luteal serum P4 levels are always sufficient to support implantation and early pregnancy. The question has become more relevant in relation to fertility treatment, as more frozen embryo transfer cycles are performed in the natural cycle. Moreover, can serum hormone levels and covariates measured during the follicular phase (FP), such as Follicle Stimulation Hormone (FSH), Luteinizing Hormone (LH), Estradiol (E2), Anti-Mullerian Hormone (AMH) and Antral Follicle Count (AFC), be used to predict P4 levels during the luteal phase (LP)?

RESULTS

This observational prospective cohort study analysed 26 healthy women with a cycle length between 21-35 days and a body mass index (BMI) < 30 kg/m2. Blood sampling started on the fifth day of the menstrual cycle and continued every fifth day until the next cycle. The procedure was repeated for a total of three cycles. The study found that only ten women had a P4 level greater than 30 nmol/L on cycle day 20 or 25 in all three cycles. In total, only 45 cycles out of 77 cycles had serum P4 levels ≥ 30 nmol/L. The E2 level ≥ 345 pmol/L on cycle day 10 proved to be predictive of a P4 level of ≥ 30 nmol/L on either day 20 or day 25 with a sensitivity of 57% and a specificity of 89%. No other covariates, including the FSH level cycle day 5, LH levels during the follicular phase, age, weight, AFC and AMH cycle day 5 correlated with LP P4 levels.

CONCLUSIONS

A significant correlation between FP E2 levels cycle day 5 (> 131pmol/L) and cycle day 10 (> 345pmol/L) and a LP P4 level ≥ 30 nmol/l was found; thus, the FP E2 level is a predictor of corpus luteum competence. Our findings highlight the existence of suboptimal P4 levels during the LP and a significant inter-individual and intra-cycle variation in P4 levels during the LP in regular menstruating women.

The hormonal control of parturition

Parturition is a complex physiological process that must occur in a reliable manner and at an appropriate gestation stage to ensure a healthy newborn and mother. To this end, hormones that affect the function of the gravid uterus, especially progesterone (P4), 17β-estradiol (E2), oxytocin (OT), and prostaglandins (PGs), play pivotal roles. P4 via the nuclear P4 receptor (PR) promotes uterine quiescence and for most of pregnancy exerts a dominant block to labor. Loss of the P4 block to parturition in association with a gain in prolabor actions of E2 are key transitions in the hormonal cascade leading to parturition. P4 withdrawal can occur through various mechanisms depending on species and physiological context. Parturition in most species involves inflammation within the uterine tissues and especially at the maternal-fetal interface. Local PGs and other inflammatory mediators may initiate parturition by inducing P4 withdrawal. Withdrawal of the P4 block is coordinated with increased E2 actions to enhance uterotonic signals mediated by OT and PGs to promote uterine contractions, cervix softening, and membrane rupture, i.e., labor. This review examines recent advances in research to understand the hormonal control of parturition, with focus on the roles of P4, E2, PGs, OT, inflammatory cytokines, and placental peptide hormones together with evolutionary biology of and implications for clinical management of human parturition.

Ideal frozen embryo transfer regime

PURPOSE OF REVIEW

This review aims to compare evidence on four criteria (embryo implantation, obstetric outcomes, patient convenience, and IVF-unit efficiency) by analyzing published research on different endometrial preparation methods for frozen embryo transfer (FET).

RECENT FINDINGS

While the artificial-FET cycle provides advantages in scheduling and implantation, it falls short in ensuring optimal obstetric outcomes. In contrast, natural-FET ensures embryo implantation conditions if ovulation is correctly identified. Supplementing with exogenous progesterone shields against low corpus luteum progesterone secretion, crucial for positive obstetric outcomes. In mNC-FET, ovulation is hCG-triggered, closely resembling natural cycles and reducing monitoring visits for enhanced patient convenience.Letrozole is a recommended option for anovulatory patients, preserving endometrial thickness. It is cost-effective, less likely to induce multifollicular development than gonadotropins, and better tolerated.In a novel approach, the natural-proliferative-phase-FET initiates progesterone in an unmediated ovulatory cycle at 7 mm endometrial thickness, combining the benefits of a natural proliferative endometrium with the convenience of scheduled artificial cycles.

SUMMARY

The artificial cycle offers scheduling advantages, but may compromise obstetric outcomes. Natural FET relies on accurate ovulation timing for successful implantation. mNC-FET simplifies the process using hCG induction, minimizing clinic visits for improved convenience. Letrozole is highlighted as a cost-effective and well tolerated option in anovulatory patients. A recent innovative approach combines elements of natural and artificial cycles, showing promise for FET procedures.

Current Ovulation and Luteal Phase Tracking Methods and Technologies for Fertility and Family Planning: A Review

Ovulation is critical for both conception and overall health, but many people who may ovulate are not tracking ovulation or any other part of their menstrual cycle. Failure to track ovulation, especially in those trying to conceive, can lead to fertility challenges due to absent ovulation, mistiming intercourse, or an undetected luteal phase defect. Ovulatory disorders and mistiming intercourse are both primary causes of infertility, and tracking ovulation is shown to decrease the average time to conception. While there are many tracking methods and apps available, the majority are predictive apps or ovulation predictor kits and do not test or track both successful ovulation and the health of the luteal phase, leading to missing information that could contribute to diagnosis or successful conception. Here, we review why ovulation tracking and a healthy luteal phase are important for those trying to conceive. We present currently available ovulation tracking methods that detect both ovulation and the luteal phase, including cervical mucus, urinary hormone testing, and basal body temperature, and discuss the use, advantages, and disadvantages of each. Finally, we consider the role of digital applications and tracking technologies in ovulation tracking.

Luteal phase support in assisted reproductive technology

Infertility affects one in six couples, with in vitro fertilization (IVF) offering many the chance of conception. Compared to the solitary oocyte produced during the natural menstrual cycle, the supraphysiological ovarian stimulation needed to produce multiple oocytes during IVF results in a dysfunctional luteal phase that can be insufficient to support implantation and maintain pregnancy. Consequently, hormonal supplementation with luteal phase support, principally exogenous progesterone, is used to optimize pregnancy rates; however, luteal phase support remains largely 'black-box' with insufficient clarity regarding the optimal timing, dosing, route and duration of treatment. Herein, we review the evidence on luteal phase support and highlight remaining uncertainties and future research directions. Specifically, we outline the physiological luteal phase, which is regulated by progesterone from the corpus luteum, and evaluate how it is altered by the supraphysiological ovarian stimulation used during IVF. Additionally, we describe the effects of the hormonal triggers used to mature oocytes on the degree of luteal phase support required. We explain the histological transformation of the endometrium during the luteal phase and evaluate markers of endometrial receptivity that attempt to identify the 'window of implantation'. We also cover progesterone receptor signalling, circulating progesterone levels associated with implantation, and the pharmacokinetics of available progesterone formulations to inform the design of luteal phase support regimens.

Initiating luteal phase support with sc progesterone based on low serum progesterone on the transfer day in true natural cycle frozen embryo transfers

Introduction

Concerning contemporary in-vitro fertilisation (IVF) practice, the use of frozen embryo transfer (FET) cycles has become more common than fresh transfers. Natural cycle (NC), programmed artificial cycle and mild stimulation cycle are primary endometrium preparation cycles. Monitoring serum progesterone levels in FET cycles are in the scope of current research focus. Low progesterone levels on the day of embryo transfer is presumed to negatively affect pregnancy outcomes, while progesterone supplementation may improve pregnancy rates. The purpose of our trial is to evaluate whether initiating subcutaneous (SC) progesterone supplementation on the day of embryo transfer when serum progesterone levels are below 10 ng/mL in tNC-FET will result in pregnancy rates comparable to those of patients with sufficient serum progesterone.

Methods

Retrospective single centre study was conducted between August 2022 and April 2023 with 181 tNC-FETs. Patients were separated into groups according to serum progesterone concentrations (≥10 ng/mL and <10 ng/mL) on embryo transfer (ET) day. S.c progesterone (25 mg) was given on the day of ET when serum progesterone was <10 ng/mL, continuing until the 10th gestational week. Blood samples for pregnancy tests were collected 12 days after ET. Outcome parameters were pregnancy rate, clinical pregnancy rate (CPR), miscarriage rate, multiple pregnancy rate, biochemical pregnancy, and ongoing pregnancy rate (OPR).

Results

About half (49.7%) had adequate progesterone concentrations (≥10ng/mL) on ET day. There was no significant difference between the groups regarding positive pregnancy test, OPR, multiple pregnancies, and miscarriage rates (57.8% versus 52.7%; 34.4% versus 29.7%, 1.1% versus 2.2%; 7.8% versus 5.5%; respectively, for progesterone concentrations on ET day ≥10 ng/mL and <10 ng/mL). With 55.2% of transfers leading to clinical pregnancy, significant differences emerged in biochemical pregnancy and CPR (3.3% vs 12.1%, P=0.02; 54.4% vs 40.7%, P=0.03, for ≥10 ng/mL and <10 ng/mL progesterone concentrations on ET day).

Discussion

This study indicates that nearly half of the tNC-FETs may need luteal phase support due to low progesterone. However, 25 mc sc progesterone rescued the luteal support and yielded similar OPR as compared to normal progesterone group. Further studies are needed for understanding optimal progesterone levels, supplementation effectiveness, and potential benefits of earlier supplementation in FETs.

Home-based monitoring of ovulation to time frozen embryo transfers in the Netherlands (Antarctica-2): an open-label, nationwide, randomised, non-inferiority trial

BACKGROUND

The growing field of assisted reproductive techniques, including frozen-thawed embryo transfer (FET), should lead the way to the best sustainable health care without compromising pregnancy chances. Correct timing of FET is crucial to allow implantation of the thawed embryo. Nowadays, timing based on hospital-controlled monitoring of ovulation in the natural cycle of a woman is the preferred strategy because of the assumption of favourable fertility prospects. However, home-based monitoring is a simple method to prevent patient travel and any associated environmental concerns. We compared ongoing pregnancy rates after home-based monitoring versus hospital-controlled monitoring with ovulation triggering.

METHODS

This open-label, multicentre, randomised, non-inferiority trial was undertaken in 23 hospitals and clinics in the Netherlands. Women aged between 18 and 44 years with a regular ovulatory menstrual cycle were randomly assigned in a 1:1 ratio via a web-based randomisation program to home-based monitoring or hospital-controlled monitoring. Those who analysed the data were masked to the groups; those collecting the data were not. All endpoints were analysed by intention to treat and per protocol. Non-inferiority was established when the lower limit of the 90% CI exceeded -4%. This study was registered at the Dutch Trial Register (Trial NL6414).

FINDINGS

1464 women were randomly assigned between April 10, 2018, and April 13, 2022, with 732 allocated to home-based monitoring and 732 to hospital-controlled monitoring. Ongoing pregnancy occurred in 152 (20·8%) of 732 in the home-based monitoring group and in 153 (20·9%) of 732 in the hospital-controlled monitoring group (risk ratio [RR] 0·99 [90% CI 0·81 to 1·22]; risk difference [RD] -0·14 [90% CI -3·63 to 3·36]). The per-protocol analysis confirmed non-inferiority (152 [21·0%] of 725 vs 153 [21·0%] of 727; RR 1·00 (90% CI 0·81 to 1·23); RD -0·08 [90% CI -3·60 to 3·44]).

INTERPRETATION

Home-based monitoring of ovulation is non-inferior to hospital-controlled monitoring of ovulation to time FET.

FUNDING

The Dutch Organisation for Health Research and Development.

Does luteal phase progesterone supplementation affect physical and psychosocial well-being among women undergoing modified natural cycle-FET? A sub-study of a randomized controlled trial

STUDY QUESTION

Are there any differences in physical and psychosocial well-being among women undergoing modified natural cycle frozen embryo transfer (mNC-FET) with or without vaginal progesterone as luteal phase support (LPS)?

SUMMARY ANSWER

Women undergoing mNC-FET with vaginal progesterone supplementation were more likely to experience physical discomfort but there was no difference in psychosocial well-being between the two groups.

WHAT IS KNOWN ALREADY

mNC-FET can be carried out with or without vaginal progesterone as LPS, which has several side-effects. It is commonly known that fertility treatment can cause stress and psychosocial strain, however, most studies on this subject are conducted in fresh cycle regimes, which differ from NC-FET and results may not be comparable.

STUDY DESIGN, SIZE, DURATION

This is a sub-study of an ongoing RCT investigating whether progesterone supplementation has a positive effect on live birth rate in mNC-FET. The RCT is conducted at eight fertility clinics in Denmark from 2019 and is planned to end primo 2024. The sub-study is based on two questionnaires on physical and psychosocial well-being added to the RCT in August 2019. On the time of data extraction 286 women had answered both questionnaires.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Women who had answered both questionnaires were included in the sub-study. Participants were equally distributed, with 143 in each of the two groups. Participants in both groups received the same questionnaires at two time-points: on cycle day 2-5 (baseline) and after blastocyst transfer. Participants in the progesterone group had administered progesterone for 7 days upon answering the second questionnaire. All items in the questionnaires were validated. Items on psychosocial well-being originate from the Copenhagen Multi-Centre Psychosocial Infertility-Fertility Problem Stress Scale (COMPI-FPSS) and from the Mental Health Inventory-5.

MAIN RESULTS AND THE ROLE OF CHANCE

Women receiving progesterone experienced more vaginal itching and/or burning than women in the non-progesterone group (P < 0.001). Women in the progesterone group also experienced more self-reported vaginal yeast infection, this was, however, not significant after adjustment for multiple testing (P/adjusted P = 0.049/0.881). No differences regarding psychosocial well-being were found between the two groups. Within the progesterone group, a shift toward feeling less 'downhearted and blue' was found when comparing response distribution at baseline and after blastocyst transfer (P < 0.001).

LIMITATIONS, REASONS FOR CAUTION

All items on physical symptoms were self-reported. The item on vaginal yeast infection was therefore not diagnosed by a doctor. Inclusion in the study required a few extra visits to the clinic, participants who felt more burdened by fertility treatment might have been more likely to decline participation. Women who experienced a lot of side-effects to progesterone prior to this FET cycle, might be less likely to participate.

WIDER IMPLICATIONS OF THE FINDINGS

Our results are in line with previous known side-effects to progesterone. Physical side-effects of progesterone should be considered before administration.

STUDY FUNDING/COMPETING INTEREST(S)

The RCT is fully supported by Rigshospitalet's Research Foundation and a grant from Gedeon Richter. Gedeon Richter were not involved in the design of protocol nor in the conduction of the study or analysis of results. A.P., L.P., and N.I.-C.F. report grants from Gedeon Richter, Ferring and Merck with no relations to this study. N.I.-C.F. has received travel support from Ferring, Merck A/S, & Gideon Richter, and is the head of the steering committee for the Danish Fertility Guidelines made by the members of from the Danish Fertility Society. A.P. reports consulting fees from Preglem, Novo Nordisk, Ferring, Gedeon Richter, Cryos, & Merck A/S, honoraria from Gedeon Richter, Ferring, Merck A/S, Theramex, and Organon, has received travel support from Gedeon Richter (payment to institution), participated on an advisory board for Preglem and was loaned an embryoscope from Gedeon Richter to their institution. A.L.S. has stock options for Novo Nordisk B A/S. B.A. have received unrestricted grant from Gedeon Richter Nordic and Merck and honoraria for lectures from Gedeon Richter, Merck, IBSA, and Marckyrl Pharma.

TRIAL REGISTRATION NUMBER

The RCT is registered on ClinicalTrials. gov (NCT03795220) and in EudraCT (2018-002207-34).