Relationship between the oestradiol/oocyte ratio and the outcome of assisted reproductive technology cycles with gonadotropin releasing hormone agonist

Can Ratios Between Prognostic Factors Predict the Clinical Pregnancy Rate in an IVF/ICSI Program with a GnRH Agonist-FSH/hMG Protocol? An Assessment of 2421 Embryo Transfers, and a Review of the Literature

None of the models developed in in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) is sufficiently good predictors of pregnancy. The aim of this study was to determine whether ratios between prognostic factors could predict the clinical pregnancy rate in IVF/ICSI. We analyzed IVF/ICSI cycles (based on long GnRH agonist-FSH protocols) at two ART centers (the second to validate externally the data). The ratios studied were (i) the total FSH dose divided by the serum estradiol level on the hCG trigger day, (ii) the total FSH dose divided by the number of mature oocytes, (iii) the serum estradiol level on the trigger day divided by the number of mature oocytes, (iv) the serum estradiol level on the trigger day divided by the endometrial thickness on the trigger day, (v) the serum estradiol level on the trigger day divided by the number of mature oocytes and then by the number of grade 1 or 2 embryos obtained, and (vi) the serum estradiol level on the trigger day divided by the endometrial thickness on the trigger day and then by the number of grade 1 or 2 embryos obtained. The analysis covered 2421 IVF/ICSI cycles with an embryo transfer, leading to 753 clinical pregnancies (31.1% per transfer). Four ratios were significantly predictive in both centers; their discriminant power remained moderate (area under the receiver operating characteristic curve between 0.574 and 0.610). In contrast, the models' calibration was excellent (coefficients: 0.943-0.978; p < 0.001). Our ratios were no better than existing models in IVF/ICSI programs. In fact, a strongly discriminant predictive model will be probably never be obtained, given the many factors that influence the occurrence of a pregnancy.

GnRH antagonist versus follicular-phase single-dose GnRH agonist protocol in patients of normal ovarian responses during controlled ovarian stimulation

OBJECTIVE

This study aims to explore the differences of the ovarian stimulation (OS) characteristics, laboratory, and clinical outcomes between follicular-phase single-dose gonadotropin-releasing hormone (GnRH) agonist protocol and GnRH antagonist protocol during controlled ovarian hyperstimulation (COH).

METHODS

About 1883 consecutive IVF/ICSI fresh cycles of normal ovarian responders were retrospectively analyzed, with 1229 in the single-dose GnRH agonist protocol group and 654 in the GnRH antagonist protocol group at Reproductive Medical Center of Tongji Hospital from 1 January 2014 to 31 December 2017.

RESULTS

The follicular-phase single-dose GnRH agonist group showed significantly more oocytes obtained, higher implantation rate and pregnancy rate, as well as lower luteinizing hormone (LH) level and estradiol (E2)/oocyte ratio on the day of human chorionic gonadotropin (hCG) administration. However, differences were not significant in meiosis II (MII) oocyte rate, two pronuclear zygote (2PN) embryo rate, viable embryo rate or high-quality embryo rate, compared with the GnRH antagonist group. Further comparison of clinical outcomes in the first frozen-thawed cycles did not show significant difference in either implantation or clinical pregnancy rate between the two protocol groups.

CONCLUSIONS

Follicular-phase single-dose GnRH agonist protocol may achieve better clinical outcomes in normal ovarian responders, which could be explained more by positive effect on endometrial receptivity rather than embryo quality.

Soluble LH-HCG receptor and oestradiol as predictors of pregnancy and live birth in IVF

RESEARCH QUESTION

Circulating soluble LH-HCG receptor (sLHCGR) is a first-trimester marker for screening pregnancy pathologies and predicts premature or multiple births before fertility treatment. Oestradiol per oocyte at ovulation induction predicts IVF treatment outcomes. We asked whether sLHCGR levels are stable during fertility treatment and whether, alone or with oestradiol, they could improve prediction of fertility treatment outcomes.

DESIGN

Serum sLHCGR, anti-Müllerian hormone [AMH] and oestradiol were measured in patients undergoing IVF. Antral follicle count before ovarian stimulation and oocyte yield were used to establish sLHCGR- oocyte ratio (SOR), sLHCGR- antral follicle ratio (SAR), oestradiol at trigger per oocyte (oestradiol-oocyte ratio [EOR]) and oestradiol at trigger per antral follicle (oestradiol-antral follicle ratio [EAR]).

RESULTS

The relatively stable sLHCGR was negatively related to AMH when oocyte yield was high. The sLHCGR levels were proportional (r = 0.49) to oestradiol at early cycle (day-3). Pregnancy and live birth were highest at low sLHCGR (≤1.0 pmol/ml) and SOR (≤ 0.1 pmol/ml/oocyte). A total of 86-89% of live births in IVF treatment were within the cut-off parameters of SAR and SOR (0.5 pmol/ml) and EAR and EOR (380 pg/ml). For failed pregnancy, age, SOR and EOR together had positive and negative predictive values of 0.841 and 0.703, respectively.

CONCLUSIONS

sLHCGR levels are negatively related to AMH when oocyte yield is high. High early cycle sLHCGR is associated with elevated day-3 oestradiol. Low sLHCGR and SOR are indicators of increased clinical pregnancy and live birth rates. Patient age and SOR, combined with EOR, might improve prediction of IVF treatment outcomes.

Potential influence of the microbiome on infertility and assisted reproductive technology

Although an altered vaginal microbiota has been demonstrated to affect parturition, its role in assisted reproductive technologies is uncertain. Nevertheless, the effect of known pathogens such as Mycoplasma tuberculosis, Chlamydia trachomatis, and Neisseria gonorrhoeae is clear, causing subclinical changes thought to be risk factors in subfertility. The Human Microbiome Project (HMP) has allowed for metagenomic studies to aid in characterizing normal vaginal flora. Recent findings from the HMP demonstrate that many different species of Lactobacillus are present in the vaginal tract, with a few that predominate. Studies that characterize the vaginal microbiome in assisted reproductive technology support the hypothesis that colonizing the transfer-catheter tip with Lactobacillus crispatus at the time of embryo transfer may increase the rates of implantation and live birth rate while decreasing the rate of infection. In addition, there is some evidence that a progesterone-resistant endometrium might increase the risk of an abnormal vaginal microbiome.

The dynamics of the vaginal microbiome during infertility therapy with in vitro fertilization-embryo transfer

PURPOSE

To determine the vaginal microbiome in women undergoing IVF-ET and investigate correlations with clinical outcomes.

METHODS

Thirty patients had blood drawn for estradiol (E(2)) and progesterone (P(4)) at four time points during the IVF-ET cycle and at 4-6 weeks of gestation, if pregnant. Vaginal swabs were obtained in different hormonal milieu, and the vaginal microbiome determined by deep sequencing of the 16S ribosomal RNA gene.

RESULTS

The vaginal microbiome underwent a transition during therapy in some but not all patients. Novel bacteria were found in 33% of women tested during the treatment cycle, but not at 6-8 weeks of gestation. Diversity of species varied across different hormonal milieu, and on the day of embryo transfer correlated with outcome (live birth/no live birth). The species diversity index distinguished women who had a live birth from those who did not.

CONCLUSIONS

This metagenomics approach has enabled discovery of novel, previously unidentified bacterial species in the human vagina in different hormonal milieu and supports a shift in the vaginal microbiome during IVF-ET therapy using standard protocols. Furthermore, the data suggest that the vaginal microbiome on the day of embryo transfer affects pregnancy outcome.