Premature progesterone elevation in controlled ovarian stimulation: to make a long story short

The late-follicular-phase progesterone to retrieved oocytes ratio in normal ovarian responders treated with an antagonist protocol can be used as an index for selecting an embryo transfer strategy and predicting the success rate: a retrospective large-scale study

Objective

To determine whether the late-follicular-phase progesterone to retrieved oocytes (P/O) ratio during in vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI) impacts pregnancy outcomes.

Design

12,874 cycles were retrospectively categorized into four groups according to the P/O ratio percentile, with divisions at the 25th, 50th and 75th percentiles.

Results

The clinical pregnancy and live birth rates of fresh cycle embryos in Group D were significantly lower than those in the other three groups (45.1% and 39.0%, 43.2% and 37.2%, 39.6% and 33.5%, 33.4% and 28.2% in Group A, B, C, D, respectively; both P < 0.008). Multivariate logistic regression analysis revealed a significant negative correlation between the P/O ratio and live birth, particularly when the P/O ratio was ≥0.22 (OR = 0.862, 95% CI [0.774-0.959], P = 0.006).

Conclusions

The P/O ratio has certain predictive value for IVF/ICSI pregnancy outcomes and can be used for decision-making decision regarding fresh embryo transfer.

Proof of concept use of progesterone/estradiol ratio to investigate late follicular progesterone in women with low number of preovulatory follicles

BACKGROUND

The aim of this study was to investigate late follicular progesterone (P) serum levels in women with a low number of preovulatory follicles in the assisted reproductive technologies (ART) setting.

METHODS

Fifty-five consecutive women having four or fewer preovulatory follicles of >14 mm on the day of human chorionic gonadotropin (hCG) administration were prospectively evaluated. Spearman correlation tests were performed between serum estradiol (E2) level, serum P level, P/E2 ratio, number of preovulatory follicles, oocytes and embryos. Women enrolled were further divided into two groups in accordance with the P/E2 ratio on the day of hCG administration and compared.

RESULTS

Serum E2 level correlated positively with P serum level (rs=0.36, P<0.01), number of mature follicles (rs=0.50, P<0.01) and number of oocytes retrieved (rs=0.36, P<0.05), whereas negatively with P/E2 ratio (rs=- 0.68, P<0.01). Likewise, number of preovulatory follicles correlated positively with E2 level (rs=0.50, P<0.01), P level (rs=0.27, P<0.05) and number of oocytes retrieved (rs=0.33, P<0.05), while it correlated negatively with P/E2 ratio (rs=-0.33, P<0.05). Furthermore, women with P/E2 ratio >1 on the day of hCG administration received considerably higher total follicular stimulating hormone (FSH) dosage and achieved significantly lower number of oocytes and embryos as compared to controls.

CONCLUSIONS

The reverse relationship between number of preovulatory follicles and P/E2 ratio implies that P rise is not only the result of increased steroidogenic activity, but other oocyte-follicle disrupted mechanisms seem to be involved. An exaggerated FSH stimulation appears to disrupt further these mechanisms.

hMG addition affects the change in progesterone level during IVF stimulation and LBR: a retrospective cohort study

BACKGROUND

Premature progesterone (P) rise during IVF stimulation reduces endometrial receptivity and is associated with lower pregnancy rates following embryo transfer (ET), which can influence provider recommendation for fresh or frozen ET. This study aimed to determine whether change in P level between in IVF baseline and trigger (𝚫P) is predictive of pregnancy outcome following fresh ET, and whether the ratio of gonadotropins influences P rise and, as a result, clinical pregnancy outcomes: clinical pregnancy rate (CPR) and live birth rates (LBR).

METHODS

Retrospective cohort study at a single fertility center at an academic institution. The peak P level and 𝚫P were modeled in relation to prediction of CPR and LBR, and the ratios of hMG:rFSH were also modeled in relation to prediction of peak P level on day of trigger, 𝚫P, and CPR/LBR in a total of 291 patients undergoing fresh embryo transfer after controlled ovarian hyperstimulation-IVF (COH-IVF).

RESULTS

𝚫P correlates with CPR, with the most predictive range for success as 𝚫P 0.7-0.85 ng/mL (p = 0.005, 95% CI 0.635, 3.636; predicting CPR of 88.9%). The optimal range for peak P in regard to pregnancy outcome was 0.15-1.349 ng/mL (p = 0.01; 95% CI for coefficient in model 0.48-3.570). A multivariable logistic model for prediction of CPR and LBR using either peak or 𝚫P supported a stronger association between 𝚫P and CPR/LBR as compared to peak P. Furthermore, an hMG:rFSH ratio of > 0.6 was predictive of lowest peak P (p = 0.010, 95% CI 0.035, 0.256) and smallest 𝚫P (p = 0.012, 95% CI 0.030, 0.243) during COH-IVF cycles. Highest CPRs were observed within hMG:rFSH ratios of 0.3-0.4 [75.6% vs. 62.5% within and outside of the range, respectively, (p = 0.023, 95% CI 0.119, 1.618)]. Highest LBRs were seen within the range of 0.3-0.6 hMG:rFSH, [LBR of 55.4% vs. 41.4% (p = 0.010, 95% CI 0.176, 1.311)].

CONCLUSIONS

Our data supports use of 𝚫P to best predict pregnancy rates and therefore can improve clinical decision making as to when fresh ET is most appropriate. Furthermore, we found optimal gonadotropin ratios can be considered to minimize P rise and to optimize CPR/LBR, emphasizing the importance of luteinizing hormone (LH) activity in COH-IVF cycles.

Effects of different progesterone levels on reproductive outcomes in assisted reproductive technologies: from molecular basis to treatment strategies

PURPOSE

The aim of this narrative review is to offer an overview about the role of progesterone levels on pregnancy outcome in patients undergoing assisted reproductive technologies (ARTs).

METHODS

A detailed computerized search of the literature was performed in the main electronic databases (MEDLINE, EMBASE, Web of Science) to determine the importance of elevated progesterone levels at different stages of the cycle for pregnancy rates in the in vitro fertilization (IVF) cycle. Our review also provides information on the differences between elevated progesterone levels and their interpretation in normal and in poorly responding women.

RESULTS

After careful evaluation, our search strategy yielded a total of 15 included articles, showing the possible factors that may have had an impact on the increased progesterone level before human chorionic gonadotropin (HCG) injection and the different thresholds above which the pregnancy rate was lower. Furthermore, increased progesterone on cycle day 2 or 3 could serve as a marker for increased progesterone in the late follicular phase, which is associated with a lower pregnancy rate.

CONCLUSION

Despite the literature data that support the negative effect of elevated progesterone on fresh cycles, due to lack of randomized controlled trials, the value of measuring progesterone in daily practice is questionable. Available evidence supports the detrimental effect of elevated progesterone in different subgroups of women, although there is still the need for defining different thresholds and durations of high progesterone exposure. The need for various thresholds for different cohorts of women, the inter-assay variability is making this decision harder.

A Narrative Review Discussing the Efficiency of Personalized Dosing Algorithm of Follitropin Delta for Ovarian Stimulation and the Reproductive and Clinical Outcomes

Background: Follitropin delta is the third recombinant human follicle-stimulating hormone (r-hFSH) expressed in a host cell line of human fetal retinal origin that currently emphasizes that the actual tendency of administration is a personalized dosing algorithm based on the anti-Müllerian hormone (AMH) and body mass index (BMI) for ovarian stimulation. Methods: In this context, we aimed, in the present manuscript, to gather all available data published between 2018-2022 regarding the co-administration and administration of follitropin delta and the clinical outcomes reported following an in vitro fertilization (IVF). Results: Follitropin delta is non-inferior in contrast to its previously launched agents for ovarian stimulation, enhancing a similar-to-superior response reflected by both the reproductive and pregnancy outcomes in parallel with a low risk of ovarian hyperstimulation syndrome (OHSS), being well tolerated. The body weight and AMH level are factors that may influence the outcome in a patient. Despite controversy and results that refute these arguments on several occasions, follitropin delta exceeds the benefits of conventional dosing with either follitropin alfa or follitropin beta. Thus, all post hoc, derived analyses and subsets of patients that participated in subsequent studies support this statement. Conclusions: Despite the relatively limited spectrum of data in the current literature, most authors brought potent proof, supporting the subsequent use of this drug depending on the patient's profile and overcoming ethnic-related limitations. Although others contradict these observations, this topic and drug possess substantial potential, which is why additional studies are mandatory to fill the existing gaps in our knowledge and expand these experiences at a larger scale supported by the obtained reproductive and clinical outcomes that clearly indicate an overcoming of all limitations.

Slightly Elevated Progesterone on HCG Trigger Day Has an Impact on Pregnancy Outcomes of Fresh Single Blastocyst Transfer Cycles Under an Early Follicular Phase Prolonged Protocol Cycle

Background

The effect of premature progesterone elevation on assisted reproductive technology has been debated. In different ovarian stimulation protocols, ovarian responses, and embryos transferred, conflicting results reside regarding the impact of elevated progesterone on pregnancy outcomes, according to previous studies. In addition, most studies have focused on significantly elevated progesterone levels, eg, above 1.5ng/mL, 1.75ng/mL, 2ng/mL. However, studies focusing on levels that are just slightly elevated are lacking, and some have concluded that such levels have no adverse effects on pregnancy outcomes.

Methods

Clinical data of patients who underwent early follicular phase prolonged protocol cycle in vitro fertilization/intracytoplasmic sperm injection treatment were collected. Patients were divided into two groups according to progesterone level on the trigger day of human chorionic gonadotropin (HCG): Group 1: < 1.0ng/mL and Group 2: 1.0-1.5ng/mL. Differences in baseline characteristics, ovulation promotion, and embryo culture, along with clinical pregnancy outcomes, were compared between the two cohorts.

Results

A total of 743 participants were included in this study, of which 587 were included in Group 1 and 156 were included in Group 2. In terms of pregnancy outcomes, Group 2 had a significantly lower clinical pregnancy rate and live birth rate per cycle than Group 1 (64.1% vs 75.7%, p < 0.05; 63.5% vs 72.7%, p < 0.05). After correction for maternal age, maternal body mass index, infertility duration, basal follicle-stimulating hormone, anti-Müllerian hormone, antral follicle count, total dose of gonadotropin, days of stimulation, and estradiol level on HCG trigger day, slightly elevated progesterone levels (P > 1.0ng/mL) remained a risk factor for pregnancy failure in fresh single D5 blastocyst transfer under an early follicular phase prolonged protocol cycle.

Conclusion

Slightly elevated progesterone levels on HCG trigger day may negatively affect pregnancy outcomes in early follicular phase prolonged protocol cycles.

Progesterone Induces Apoptosis and Steroidogenesis in Porcine Placental Trophoblasts

Placentation and placental steroidogenesis are important for pregnancy and maternal−fetal health. As pregnancy progresses, the main site of progesterone (P4) synthesis changes from the corpus luteum to the placenta, in which placental trophoblasts are the main cell type for P4 synthesis. Therefore, this study investigated the effects of P4 on apoptosis and steroidogenesis in porcine placental trophoblasts and the underlying molecular mechanisms. Porcine placental trophoblasts were treated with different concentrations of P4 for 48 h in a serum-free medium in vitro. Cell number, steroidogenesis, and relevant gene and protein expression levels were detected. A high dose of P4 (10.0 μM) significantly increased P4 (p < 0.01), androstenedione (p < 0.05), testosterone (p < 0.05), and estradiol (p < 0.05) production in porcine placental trophoblasts compared with that in control cells, while a low dose of P4 (1 × 10−3 μΜ) had no marked impact on steroid production. The mRNA expression of apoptosis-related genes (CASP3, CASP8, and Bax) (p < 0.05) and steroidogenesis-related genes (CYP11A1, CYP19A1, and StAR) (p < 0.01) was upregulated, and the expression of HSD3B and HSD17B4 was inhibited (p < 0.05) in the porcine placental trophoblasts treated with high doses of P4. Low doses of P4 had a lighter effect on gene expression than high doses. The expression of apoptosis-related proteins CASP3 (p < 0.05), and Bax (p < 0.01) and steroidogenesis-related proteins CYP19A1 (p < 0.05) and StAR (p < 0.01) was raised, but the proliferation-related protein CCND2 (p < 0.01) was downregulated in the pTr cells treated with high dose of P4. In comparison, a low dose of P4 inhibited the expression of Bax, CYP11A1 (all p < 0.01), and CCND2 (p < 0.05), but the expression of CASP3 (p < 0.05) and StAR (p < 0.01) was upregulated. In summary, excessive P4 can induce the apoptosis of porcine placental trophoblasts and lead to abnormal steroidogenesis in the placenta and hormone imbalance.

Lipid metabolism and endometrial receptivity

BACKGROUND

Obesity has now been recognized as a high-risk factor for reproductive health. Although remarkable advancements have been made in ART, a considerable number of infertile obese women still suffer from serial implantation failure, despite the high quality of embryos transferred. Although obesity has long been known to exert various deleterious effects on female fertility, the underlying mechanisms, especially the roles of lipid metabolism in endometrial receptivity, remain largely elusive.

OBJECTIVE AND RATIONALE

This review summarizes current evidence on the impacts of several major lipids and lipid-derived mediators on the embryonic implantation process. Emerging methods for evaluating endometrial receptivity, for example transcriptomic and lipidomic analysis, are also discussed.

SEARCH METHODS

The PubMed and Embase databases were searched using the following keywords: (lipid or fatty acid or prostaglandin or phospholipid or sphingolipid or endocannabinoid or lysophosphatidic acid or cholesterol or progesterone or estrogen or transcriptomic or lipidomic or obesity or dyslipidemia or polycystic ovary syndrome) AND (endometrial receptivity or uterine receptivity or embryo implantation or assisted reproductive technology or in vitro fertilization or embryo transfer). A comprehensive literature search was performed on the roles of lipid-related metabolic pathways in embryo implantation published between January 1970 and March 2022. Only studies with original data and reviews published in English were included in this review. Additional information was obtained from references cited in the articles resulting from the literature search.

OUTCOMES

Recent studies have shown that a fatty acids-related pro-inflammatory response in the embryo-endometrium boundary facilitates pregnancy via mediation of prostaglandin signaling. Phospholipid-derived mediators, for example endocannabinoids, lysophosphatidic acid and sphingosine-1-phosphate, are associated with endometrial receptivity, embryo spacing and decidualization based on evidence from both animal and human studies. Progesterone and estrogen are two cholesterol-derived steroid hormones that synergistically mediate the structural and functional alterations in the uterus ready for blastocyst implantation. Variations in serum cholesterol profiles throughout the menstrual cycle imply a demand for steroidogenesis at the time of window of implantation (WOI). Since 2002, endometrial transcriptomic analysis has been serving as a diagnostic tool for WOI dating. Numerous genes that govern lipid homeostasis have been identified and, based on specific alterations of lipidomic signatures differentially expressed in WOI, lipidomic analysis of endometrial fluid provides a possibility for non-invasive diagnosis of lipids alterations during the WOI.

WIDER IMPLICATIONS

Given that lipid metabolic dysregulation potentially plays a role in infertility, a better understanding of lipid metabolism could have significant clinical implications for the diagnosis and treatment of female reproductive disorders.

Towards an Improved Understanding of the Effects of Elevated Progesterone Levels on Human Endometrial Receptivity and Oocyte/Embryo Quality during Assisted Reproductive Technologies

Ovarian stimulation is an indispensable part of IVF and is employed to produce multiple ovarian follicles. In women who undergo ovarian stimulation with gonadotropins, supraphysiological levels of estradiol, as well as a premature rise in progesterone levels, can be seen on the day of hCG administration. These alterations in hormone levels are associated with reduced embryo implantation and pregnancy rates in IVF cycles with a fresh embryo transfer. This article aims to improve the reader’s understanding of the effects of elevated progesterone levels on human endometrial receptivity and oocyte/embryo quality. Based on current clinical data, it appears that the premature rise in progesterone levels exerts minimal or no effects on oocyte/embryo quality, while advancing the histological development of the secretory endometrium and displacing the window of implantation. These clinical findings strongly suggest that reduced implantation and pregnancy rates are the result of a negatively affected endometrium rather than poor oocyte/embryo quality. Understanding the potential negative impact of elevated progesterone levels on the endometrium is crucial to improving implantation rates following a fresh embryo transfer. Clinical studies conducted over the past three decades, many of which have been reviewed here, have greatly advanced our knowledge in this important area.

Clinical outcomes of potential high responders after individualized FSH dosing based on anti-Müllerian hormone and body weight

RESEARCH QUESTION

How does the efficacy and safety of individualized follitropin delta dosing compare with conventional dosing for ovarian stimulation in potential high responders?

DESIGN

Retrospective analysis of 153 potential high responders identified on the basis of baseline serum anti-Müllerian hormone (AMH) levels above 35 pmol/l, who were originally randomized to an individualized fixed dose of follitropin delta based on AMH and body weight (n = 78) or to a daily starting dose of 150 IU follitropin alfa (n = 75).

RESULTS

At the end of stimulation, patients treated with individualized follitropin delta or conventional follitropin alfa had 12.1 ± 7.0 and 18.3 ± 7.0 (P < 0.001) follicles measuring 12 mm or wider, and 27.3% and 62.7% had serum progesterone levels higher than 3.18 nmol/l (P < 0.001), respectively. Overall number of oocytes in these two respective arms was 9.3 ± 6.7 and 17.9 ± 8.7 (P < 0.001), and the ongoing pregnancy rate per started cycle after fresh blastocyst transfer was 28.2% and 24.0%. The risk of ovarian hyperstimulation syndrome (OHSS) for all cases was three times higher in the conventional follitropin alfa arm at 16.0% versus 5.1% with individualized follitropin delta treatment (P = 0.025) and 26.7% versus 7.7% (P = 0.001) for early moderate or severe OHSS, preventive interventions for early OHSS, or both.

CONCLUSIONS

Treatment with individualized follitropin delta provides an improved efficacy-safety balance in women with high ovarian reserve, as it normalizes the ovarian response and decreases the risk of OHSS without compromising the chance of pregnancy.

Repeated hyperstimulation affects the ultrastructure of mouse fallopian tube epithelium

Controlled ovarian hyperstimulation (COH) is routinary used in assisted reproductive technologies (ARTs) to increase the yields of mature oocytes. The possibility that patients with a history of failures or poor-responders may develop side-effects following these treatments is still debated. Epidemiological studies reported controversial results about pregnancy outcome and the risk of developing gynecological cancers. By using a mouse model, here we compared the ultrastructural features of fallopian tubes (FTs) obtained from mice undergoing or not (control, CTR) four (4R) and eight (8R) rounds of gonadotropin stimulation. Although the morphological characteristics of oviductal layers seemed unaffected by repeated treatments, dose-response ultrastructural alterations in the ampulla appeared in the 4R group and even more in the 8R group. The targets were oviductal ciliated (CCs) and non-ciliated (NCCs) cells, which showed damaged mitochondria and glycogen accumulations in the cytoplasm. The drastic reduction of CCs, evident after 4R, was supported by the absence of cilia. After 8R, glycogen granules were significantly reduced and massive degeneration of mitochondria, which appeared swollen and/or vacuolated, occurred in NCCs. Moreover, disintegrated mitochondria were found at the periphery of mitophagic vacuoles with evident signs of cristolysis. The morphometric analysis evidenced a significant increase in the density and frequency of damaged mitochondria after 4R and 8R. The absence of cilia, necessary to sustain oviductal transport of oocytes, spermatozoa and embryos, may originate from either mitochondrial dysfunction or glycogen consumption. These results suggest that repeated COH treatments could induce alterations impairing fertilization and embryo transport toward the uterus.

Influence of human chorionic gonadotrophin during ovarian stimulation: an overview

It is widely known that luteinising hormone (LH) and human chorionic gonadotrophin (hCG) are integral in the female reproductive lifecycle. Due to the common binding site and similarity in molecular structure, they were previously thought to have overlapping roles. However, with the development of both purified urinary-derived and recombinant gonadotrophins, the individual characteristics of these molecules have begun to be defined. There is evidence to suggest that LH and hCG preferentially activate different signalling cascades and display different receptor-binding kinetics. The data generated on the two molecules have led to an improved understanding of their distinct physiological functions, resulting in a debate among clinicians regarding the most beneficial use of LH- and hCG-containing products for ovarian stimulation (OS) in assisted reproductive technologies (ARTs). Over the past few decades, a number of trials have generated data supporting the use of hCG for OS in ART. Indeed, the data indicated that hCG plays an important role in folliculogenesis, leads to improved endometrial receptivity and is associated with a higher quality of embryos, while presenting a favourable safety profile. These observations support the increased use of hCG as a method to provide LH bioactivity during OS. This review summarises the molecular and functional differences between hCG and LH, and provides an overview of the clinical trial data surrounding the use of products for OS that contain LH bioactivity, examining their individual effect on outcomes such as endometrial receptivity, oocyte yield and embryo quality, as well as key pregnancy outcomes.

Effects of hormone replacement therapy on endometrial hormone concentrations and progesterone receptor expression in recurrent pregnancy loss: a self-controlled study

AIM

To investigate the differential effects of endometrial preparation approaches, natural cycle (NC) and hormone replacement therapy (HRT), on the endometrial hormone conditions in patients with recurrent pregnancy loss (RPL).

METHODS

42 RPL patients were recruited, and a self-controlled trial was conducted to compare the effectiveness of NC to HRT on the same patient. The estradiol (E2) and progesterone (P) levels in both serum and endometrial tissue were measured in NC and HRT, respectively. Meanwhile, the expression levels of endometrial progesterone receptor A (PRA) and progesterone receptor B (PRB) were also compared between NC and HRT cycles during the window of receptivity. All statistical analyses were performed using GraphPad Prism 5, and data were averaged across subjects and tested for significance by pair-samples t-test.

RESULTS

Hormone replacement slightly decreased serum E2 and P levels (0.9- and 0.8-fold in average, respectively), significantly elevated endometrial E2 and P (2.1- and 14.5-fold in average, respectively), and reduced endometrial E2/P ratio (0.34-fold in average) compared to the NC condition. However, no correlation was found between serum and endometrial hormone concentrations. Further, the PRA/PRB ratios of both stromal and glandular cells were comparable between HRT and NC conditions, even though stromal PRA expression was slightly elevated by HRT compared to NC (1.63±0.96 vs 1.18±0.99, p =.0173).

CONCLUSION

The effects of HRT for endometrial preparation are similar or slightly superior to NC in RPL patients.

The role of progesterone/estradiol ratio in exploring the mechanism of late follicular progesterone elevation in low ovarian reserve women

Late follicular progesterone (P) elevation continues to complicate a significant part of assisted reproductive technologies (ART) cycles, despite the ardent employment of gonadotropin releasing hormone (GnRH) analogues. In women with good ovarian reserve, late follicular P elevation is believed to be the result of the controlled ovarian stimulation (COS) itself, multiple follicular development and excessive ovarian steroidogenic activity. These mechanisms do not seem to be plausible in women with low ovarian reserve. In these women, excessive COS achieve a small number of pre-ovulatory follicles, which is not coupled to considerable ovarian steroidogenic activity. Therefore, other mechanisms should be pursued and explored. Delicate paracrine and autocrine mechanisms within the oocyte-cumulus complex were suggested to preserve the integrity of the pre-ovulatory follicle, including inhibition of P increase and follicular luteinization. However, clinical studies to demonstrate the disruption of these mechanisms in cases with low ovarian reserve and ageing oocytes are still lacking. Late follicular progesterone/estradiol (P/E₂) ratio was introduced into clinical practice as a more appropriate way to analyze P rise in women undergoing COS to control for the E₂ increase. The current hypothesis claims that in a follicular environment were the mechanism that prevent premature luteinization is disrupted, independent to LH surge; P rise at the late follicular phase may relatively bypass normal E₂ production, at the pre-ovulatory stage of steroidogenesis, causing a rise in the P/E₂ ratio. Therefore, in women with low ovarian reserve and few pre-ovulatory follicles, undergoing conventional COS, a negative (reverse) correlation between number of maturing follicles and P/E₂ ratio may support the existence of such a mechanism as its disruption, while a no or a positive correlation may disapprove it.