Assessment of theca cell function: a prerequisite to androgen or luteinizing hormone supplementation in poor responders

Single-cell RNA-seq analysis and cell-cluster deconvolution of the human preovulatory follicular fluid cells provide insights into the pathophysiology of ovarian hyporesponse

Reduction in responsiveness to gonadotropins or hyporesponsiveness may lead to the failure of in vitro fertilization (IVF), due to a low number of retrieved oocytes. The ovarian sensitivity index (OSI) is used to reflect the ovarian responsiveness to gonadotropin stimulation before IVF. Although introduced to clinical practice already years ago, its usefulness to predict clinical outcomes requires further research. Nevertheless, pathophysiological mechanisms of ovarian hyporesponse, along with advanced maternal age and in younger women, have not been fully elucidated. Follicles consist of multiple cell types responsible for a repertoire of biological processes including responding to pituitary gonadotropins necessary for follicle growth and oocyte maturation as well as ovulation. Encouraging evidence suggests that hyporesponse could be influenced by many contributing factors, therefore, investigating the variability of ovarian follicular cell types and their gene expression in hyporesponders is highly informative for increasing their prognosis for IVF live birth. Due to advancements in single-cell analysis technologies, the role of somatic cell populations in the development of infertility of ovarian etiology can be clarified. Here, somatic cells were collected from the fluid of preovulatory ovarian follicles of patients undergoing IVF, and RNA-seq was performed to study the associations between OSI and gene expression. We identified 12 molecular pathways differentially regulated between hypo- and normoresponder patient groups (FDR<0.05) from which extracellular matrix organization, post-translational protein phosphorylation, and regulation of Insulin-like Growth Factor (IGF) transport and uptake by IGF Binding Proteins were regulated age-independently. We then generated single-cell RNA-seq data from matching follicles revealing 14 distinct cell clusters. Using cell cluster-specific deconvolution from the bulk RNA-seq data of 18 IVF patients we integrated the datasets as a novel approach and discovered that the abundance of three cell clusters significantly varied between hypo- and normoresponder groups suggesting their role in contributing to the deviations from normal ovarian response to gonadotropin stimulation. Our work uncovers new information regarding the differences in the follicular gene expression between hypo- and normoresponders. In addition, the current study fills the gap in understanding the inter-patient variability of cell types in human preovulatory follicles, as revealed by single-cell analysis of follicular fluid cells.

Changes in clinical and biochemical characteristics of polycystic ovary syndrome with advancing age

OBJECTIVE

To verify whether aging can modify the clinical and biochemical characteristics of women with polycystic ovary syndrome (PCOS).

MATERIAL AND METHODS

This observational cross-sectional study was conducted at the reproductive endocrinology clinics of Julio Muller University Hospital and Tropical Institute of Reproductive Medicine in Cuiabá, MT, Brazil, between 2003 and 2017. Both, 796 PCOS and 444 non-PCOS normal cycling women underwent the same examination. PCOS was diagnosed using the Rotterdam criteria as recommended for adolescent and adult subjects. Anthropometric, metabolic, and endocrinological modifications with aging were initially examined in the two groups: control and PCOS. Further analyses were performed after a 5-year age stratification of data throughout the reproductive period. All participants signed a consent form approved by the local ethical committee.

RESULTS

Biomarkers of adiposity were more remarkable in African descendant PCOS women. Body weight, waist/hip ratio, fat mass, and BMI were higher in PCOS women and tended to increase at all 5 age-strata, between ≤19 and 35 years of age. Serum androgen levels decreased with aging, markedly in PCOS subjects (P < 0.01 for all age-strata comparisons), but remained elevated when compared with the levels found in controls. Carbohydrate markers, triglycerides, and total cholesterol tended to increase over time in PCOS (P < 0.01 for all age-strata comparisons). Total cholesterol also tended to increase with age in non-PCOS women (P = 0.041).

CONCLUSION

The present study has shown that the advancing age influences many features of PCOS women. Biochemical hyperandrogenism, the core criterion recommended in the current systems to define the syndrome, showed statistically significant tendencies to decrease with aging progression but did not normalize. The use of age-adjusted features for the diagnosis of PCOS are recommended.

Ovarian and adrenal androgens may be useful markers to predict oocyte competence and embryo development in older women

The aim of this retrospective analysis was to evaluate the association between serum levels of various hormones and in vitro fertilization (IVF) parameters in poor responder patients. Serum levels of anti-Müllerian hormone (AMH), dehydroepiandrosterone sulfate (DHEAS), androstenedione and testosterone were measured before the start of IVF treatment cycle. We found that serum AMH and DHEAS levels were positively correlated with the number of mature oocytes, fertilized oocytes and developed embryos, both in pregnant and in non-pregnant patients. In contrast, we found a positive correlation between serum androstenedione levels and IVF parameters in pregnant, but not in non-pregnant patients. In this latter group, androstenedione levels were positively associated with the number of mature oocytes and were negatively correlated with the number of fertilized oocytes. No correlation was observed with developed embryos. Finally, we reported a negative correlation between serum levels of testosterone and IVF parameters in pregnant women whereas no correlation was observed in non-pregnant patients. Our results suggest that serum AMH and DHEAS could be predictive for oocyte retrieval and embryo development. Moreover, the positive correlation between serum androstenedione levels and IVF parameters in pregnant patients, together with the lack of a consistent correlation in non-pregnant women seem to identify androstenedione as a more predictive marker for pregnancy outcome than testosterone. In addition, in our analysis testosterone shows a negative correlation with IVF parameters.

Recombinant LH administration in subsequent cycle after "unexpected" poor response to recombinant FSH monotherapy

Abstract Poor ovarian response (POR) is most frequently linked to the condition known as diminished ovarian reserve, but it can also occur in the absence of pathological ovarian reserve tests ("unexpected" POR). Because possible explanations include theca cells function deficiency, our aim was to evaluate the effect of r-LH administration in "unexpected" poor responders. A retrospective, single-centre, cohort study was conducted on 65 patients with AMH >0.5 ng/ml and/or AFC >5 with POR in their first cycle. Patients underwent a second IVF cycle with same protocol (long- or antagonist) and same starting dose of r-FSH used in the first cycle, plus daily addiction of 150 IU of r-LH from day 1. Compared to the first cycle, r-LH addition in the second cycle determined an increase in number of oocytes retrieved (p < 0.001), number of metaphase II oocytes (p < 0.05), E2 levels at hCG triggering (p < 0.001) and number of embryos transferred (p = 0.002). A 15% clinical pregnancy rate was also observed in the second cycle. Our results suggest that patients with non-pathological ovarian reserve tests and previous "unexpected" POR seem to benefit from r-LH addition in subsequent cycles without the need to increase the r-FSH starting dose, possibly due to an underlying occult theca cells deficiency.