P-676 Luteal phase progesterone support in modified natural cycle frozen-thawed embryo transfer (mNC-FET): a systematic review and meta-analysis
Bibliographic record
Abstract
Abstract Study question Does luteal phase progesterone supplementation effect the live birth rate (LBR), clinical pregnancy rate (CPR) or pregnancy loss rate (PLR) in mNC-FET? Summary answer The use of progesterone supplementation may affect CPR but does not significantly affect the LBR in mNC-FET. What is known already Fresh embryo transfer has been the standard procedure in assisted reproductive technology, but advancements in cryopreservation techniques, particularly vitrification, have established frozen-thawed embryo transfer (FET) as a viable alternative. A frequently used FET protocol is mNC-FET, in which ovulation is induced by exogenous human chorionic gonadotropin (hCG). Exogenous hCG supports the formation of a corpus luteum and the secretion of progesterone before implantation. Whether women should receive luteal phase support (LPS) in mNC-FET with endogenous progesterone production remains highly controversial. Study design, size, duration A systematic literature search was conducted in PubMed, EMBASE, and Cochrane Library using MeSH terms, Emtree terms, and text words in English related to progesterone LPS in mNC-FET up to October 2024. No limitations were applied regarding year of publication or duration of the studies. Randomized controlled trials (RCTs), retrospective and prospective cohort studies were eligible for inclusion. This systematic review incorporated data from our recently finalized large (n = 608), unpublished RCT evaluating LPS in mNC-FET. Participants/materials, setting, methods The inclusion criteria for eligible studies were women aged 18–46 undergoing mNC-FET with either progesterone as LPS, administered through various regimens, or no LPS, in both public and private hospital settings. Covidence was used for sorting and screening the studies to confirm their eligibility. Potential risk of bias was assessed using ROB2 for RCT’s and Newcastle-Ottawa Scale for retrospective cohort studies. Main results and the role of chance Out of 3,916 search results, six relevant studies were identified, and with inclusion of data from our recently finalized yet unpublished RCT, a total of seven studies were included in this review. Three of the included studies were RCTs and four were retrospective cohort studies. Overall, a total of 1680 women were included in the systematic review; 897 women received progesterone as LPS, and 783 did not. Out of the six studies, four studies, including the three RCTs, found no advantage of using progesterone LPS in mNC-FET. All four studies had low to high risk of bias. Two retrospective studies with low to moderate risk of bias found a positive effect of LPS and reproductive outcomes. The meta-analysis showed no significant difference in LBR between no LPS (n = 415) and progesterone LPS (n = 480), with a pooled OR of 1.28 (95% CI 0.96-1.70). CPR was significantly higher following progesterone LPS (n = 897) compared to no LPS (n = 783), with a pooled OR of 1.27 (95% CI 1.03-1.57). This review is the largest systematic review to date investigating the effect of progesterone LPS in mNC-FET. Limitations, reasons for caution Limitations of this review include high study heterogeneity, the retrospective design of three of the included studies carrying an inherent risk of bias and the lack of confounder adjustment in three retrospective studies. Wider implications of the findings This systematic review suggests that most women do not benefit from LPS regarding LBR in mNC-FET, implicating a need to revise current treatment protocols to avoid unnecessary use of medication as progesterone is known to cause physical discomfort, which can be avoided. Trial registration number No
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How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.004 | 0.001 |
| Meta-epidemiology (narrow) | 0.001 | 0.001 |
| Meta-epidemiology (broad) | 0.012 | 0.002 |
| Bibliometrics | 0.001 | 0.001 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.001 | 0.001 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".