Androgen supplementation in assisted reproduction: where are we in 2019?

Androgens and diminished ovarian reserve: the long road from basic science to clinical implementation. A comprehensive and systematic review with meta-analysis

OBJECTIVE

This study aimed to present a narrative review regarding androgen production, androgens' role in folliculogenesis, and the available therapeutic approaches for androgen supplementation, and to perform a systematic review and meta-analysis regarding the impact of androgens (dehydroepiandrosterone/testosterone) compared with placebo or no treatment on ovarian response and pregnancy outcomes in patients with diminished ovarian reserve and/or poor ovarian responders.

DATA SOURCES

An electronic search of MEDLINE, Embase, Cochrane Library, Cochrane Central Register of Controlled Trials, Scopus, ClinicalTrials.gov, the ISRCTN registry, and the World Health Organization International Clinical Trials Registry, was conducted for studies published until September 2021.

STUDY ELIGIBILITY CRITERIA

Randomized controlled trials that compared ovarian response and/or pregnancy outcomes between the different in vitro fertilization protocols using androgens (ie, dehydroepiandrosterone and testosterone) and conventional in vitro fertilization stimulation in patients with diminished ovarian reserve and/or poor ovarian responders were included.

METHODS

The quality of each study was evaluated with the revised Cochrane risk-of-bias tool for randomized trials (RoB 2). The meta-analysis used random-effects models. All results were interpreted on the basis of intention-to-treat analysis (defined as the inclusion of all randomized patients in the denominator). Risk ratios and 95% confidence intervals were used and combined for meta-analysis.

RESULTS

No significant differences were found regarding the number of oocytes retrieved (mean difference, 0.76; 95% confidence interval, -0.35 to 1.88), mature oocytes retrieved (mean difference, 0.25; 95% confidence interval, -0.27 to 0.76), clinical pregnancy rate (risk ratio, 1.17; 95% confidence interval, 0.87-1.57), live-birth rate (risk ratio, 0.97; 95% confidence interval, 0.47-2.01), or miscarriage rate (risk ratio, 0.80; 95% confidence interval, 0.29-2.22) when dehydroepiandrosterone priming was compared with placebo or no treatment. Testosterone pretreatment yielded a higher number of oocytes retrieved (mean difference, 0.94; 95% confidence interval, 0.46-1.42), a higher clinical pregnancy rate (risk ratio, 2.07; 95% confidence interval, 1.33-3.20), and higher live-birth rate (risk ratio, 2.09; 95% confidence interval, 1.11-3.95).

CONCLUSION

Although dehydroepiandrosterone did not present a clear effect on outcomes of assisted reproductive techniques, we found a potentially beneficial effect of testosterone priming on ovarian response and pregnancy outcomes. However, results should be interpreted with caution, taking into account the low to moderate quality of the available evidence.

Androgens improve ovarian follicle function impaired by glucocorticoids through an androgen-IGF1-FSH synergistic effect

High concentrations of glucocorticoids caused by chronic stress are known to affect ovarian function and cause diminished ovarian reserve. Androgens are essential for early-stage ovarian follicle development, but the effects and mechanisms of androgens on follicle development under chronic stress remain unclear. In this study, we aim to investigate the effects of high concentrations of glucocorticoids on the function of in vitro cultured ovarian cells and mouse early-stage ovarian follicles and to validate the hypothesis that androgen-insulin-like growth factor 1 (IGF1)-follicle-stimulating hormone (FSH) synergistic signaling helps to ameliorate the damage caused by high concentrations of glucocorticoids. KGN cells (human granulosa cell line) and mouse primary cells were treated with different concentrations of glucocorticoids, and the cell proliferation, apoptosis, and sex hormone secretion were detected. The effects of glucocorticoid and androgens on IGF1 receptor (IGF1R) and FSH receptor (FSHR) expression in KGN cells were detected by Western blot. Steroidogenic synthase expressions under androgens and androgen-IGF1-FSH combination treatment were examined by qPCR after manipulation using low and high concentrations of glucocorticoids. The mechanism of androgen regulation of IGF1R and FSHR was explored by small interfering RNA (siRNA) and chromatin immunoprecipitation (ChIP)-qPCR. Damage of glucocorticoids and the treatment effects of androgens were further validated in mouse ovarian follicles cultured in vitro. The results demonstrated that prolonged treatment with high-dose glucocorticoids reduced cell viability of granulosa cells, inhibited their sex hormone secretion, and impaired their sensitivity to IGF1 and FSH signaling by affecting IGF1R and FSHR functions. Androgens at an appropriate dose range improved early-stage follicle development and their hormone secretion under high-dose glucocorticoid treatment, which was related to increased transcription of Igf1r and Fshr. This work showed that excessive glucocorticoids impaired ovarian function and validated that balanced concentrations of androgens synergized with IGF1 and FSH to improve the function of early-stage ovarian follicles under conditions of chronic stress.

A Proper Increasing in the Testosterone Level May Be Associated With Better Pregnancy Outcomes for Patients With Tubal or Male Infertility During in vitro Fertilization/Intracytoplasmic Sperm Injection

We aimed to investigate the relationship between testosterone (T) levels and pregnancy outcomes in patients with tubal or male infertility at different times during in vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI) cycles. Patients with tubal or male infertility and normal androgen levels undergoing IVF/ICSI were consecutively recruited. We performed a longitudinal analysis of T levels at three time points (i.e., T0: baseline, T1: trigger day, and T2: day after the trigger day) in three groups with different pregnancy outcomes (i.e., group 1: no pregnancy; group 2: clinical pregnancy but no live birth; and group 3: live birth) as repeated measurement data using linear mixed-effects models. We also plotted fitted curves depicting the relationship between T levels and a number of oocytes retrieved at different time points and identified the inflection points of the curves. In total, 3,012 patients were recruited. Groups 1 and 3 had improvements in T levels at the three time points. After refitting, the slope in group 3 was significantly higher than that in group 1 (P = 0.000). Curves that reflected the association between T levels and numbers of retrieved oocytes presented an upward trend before a certain inflection point, after which the curves had no obvious changes or fell with increasing T levels. The inflection points for T0, T1, and T2 were calculated as 0.45, 0.94, and 1.09, respectively. A faster upward trend in T levels might be associated with better pregnancy outcomes. Within a range lower than a T level inflection point, more oocytes and embryos could be obtained with increasing T levels.

Androgens and Anti-Müllerian Hormone in Infertile Patients

To investigate whether there is an association between androgens and ovarian reserve, expressed through anti-Mullerian hormone. This is a retrospective cross-sectional analysis of all consecutive women attending a tertiary fertility center, who presented with regular menstrual cycles. Patients had their AMH values measured with the same AMH assay (Immunotech (IOT) Beckmann Coulter assay), the same day in which androgens sampling was performed. Women with PCOS or other forms of androgen excess or untreated endocrine or metabolic disorders were excluded. A total of 942 women were included. Significant correlation was observed between total testosterone/free androgens index (FAI)/DHEAS and AMH (Spearman's r = 0.20/0.14/0.13, P value < 0.001, P value < 0.001, and P value < 0.001, respectively). After multiple linear regression analysis adjusting for confounders (age, BMI, cause of infertility, day of the menstrual cycle when the blood sample was performed), the regression slope in all participants for total testosterone predicting logAMH was 0.20 (P value < 0.001). Similarly, FAI was significantly associated with logAMH (regression coefficient = 0.04, P value = 0.04). In contrast, DHEAS was not significantly associated with logAMH. There was a significant, but weak relation between testosterone and AMH, while no significant association was observed between DHEAS and AMH. Future research is needed to elucidate whether testosterone supplementation may have any effect on ovarian function.

Fresh and cumulative live birth rates in mild versus conventional stimulation for IVF cycles in poor ovarian responders: a systematic review and meta-analysis

STUDY QUESTION

Are cumulative and live birth rates (LBRs) comparable in poor ovarian response women treated with different protocols of mild stimulation IVF (i.e. oral compounds, lower doses or shorter treatments) versus conventional IVF?

SUMMARY ANSWER

Mild ovarian stimulation (MOS) results in comparable outcomes to those of conventional stimulation in poor ovarian response patients with low ovarian reserve.

WHAT IS KNOWN ALREADY

Several randomized trials and meta-analyses have been published evaluating the role of mild (MOS) versus conventional ovarian stimulation in poor ovarian response patients. Most report a potentially higher safety profile, patient satisfaction and lower costs, suggesting that the higher cycle cancellation rate and fewer oocytes retrieved following MOS does not affect the final reproductive outcome. Additionally, over the last few years, new publications have added data regarding MOS, and shown the possible benefit of a higher oocyte yield which may also improve prognosis in patients with poor ovarian response.

STUDY DESIGN SIZE DURATION

We conducted a systematic search of relevant randomized controlled trials (RCTs). We searched electronic databases, including MEDLINE, EMBASE, LILACS-BIREME, CINAHL, The Cochrane Library, CENTRAL (Cochrane Register), Web of Science, Scopus, Trip Database and Open Grey, to identify all relevant studies published up to March 2020. We examined trial registries for ongoing trials. No publication-year or language restrictions were adopted. We explored the reference list of all included studies, reviews and abstracts of major scientific meetings. The primary outcomes were cumulative and fresh LBR (CLBR and FLBR) per woman randomized.

PARTICIPANTS/MATERIALS SETTING METHODS

We included subfertile women undergoing IVF/ICSI characterized as poor responders and compared primary and secondary outcomes between the different protocols of mild stimulation IVF (i.e. oral compounds, lower doses or shorter treatments) and conventional IVF. We used the PICO (Patients, Intervention, Comparison and Outcomes) model to select our study population.

MAIN RESULTS AND THE ROLE OF CHANCE

Overall, 15 RCTs were included in the meta-analysis. CLBR and FLBR were comparable between mild versus conventional stimulation (RR 1.15; 95% CI: 0.73 - 1.81; I2 = 0%, n = 424, moderate certainty and RR 1.01; 95% CI: 0.97 - 1.04; I 2 = 0%, n = 1001, low certainty, respectively). No difference was observed either when utilizing oral compounds (i.e. letrozole and clomiphene) or lower doses. Similarly, ongoing pregnancy rate (OPR) and clinical pregnancy rate (CPR) were equivalent when comparing the two groups (RR 1.01; 95% CI: 0.98 - 1.05; I 2 = 0%, n = 1480, low certainty, and RR 1.00; 95% CI: 0.97 - 1.03; I2 = 0%, n = 2355, low certainty, respectively). A significantly lower oocyte yield (mean differences (MD) -0.80; 95% CI: -1.28, -0.32; I2 = 83%, n = 2516, very low certainty) and higher rate of cycle cancellation (RR 1.48; 95% CI: 1.08 - 2.02; I2 = 62%, n = 2588, low certainty) was observed in the MOS group.

LIMITATIONS REASONS FOR CAUTION

The overall quality of the included studies was low to moderate. Even though strict inclusion criteria were used, the selected studies were heterogeneous in population characteristics and treatment protocols. We found no differences in CLBR between MOS and COS (95% CI: 0.73 - 1.81.).

WIDER IMPLICATIONS OF THE FINDINGS

MOS could be considered as a treatment option in low prognosis poor responder patients, given that it results in similar fresh and CLBRs compared with COS. A milder approach is associated with a lower number of oocytes retrieved and a higher cancellation rate, although treatment cost is significantly reduced. Future research should focus on which type of ovarian stimulation may be of benefit in better prognosis women.

STUDY FUNDING/COMPETING INTERESTS

There were no sources of financial support. N.P.P. received research grants, honoraria for lectures from: Merck Serono, MSD, Ferring Pharmaceuticals, Besins International, Roche Diagnostics, IBSA, Theramex and Gedeon Richter. P.D. received unrestricted grants and honoraria from Merck Serono, MSD and Ferring Pharmaceuticals. I.G.F. received unrestricted grants and honoraria from Merck Serono, MSD, Ferring Pharmaceuticals, Gedeon-Richter and IBSA. P.M.B. reported no conflict of interest.

TRIAL REGISTRATION NUMBER

CRD42020167260.

What Is the Best Regimen for Ovarian Stimulation of Poor Responders in ART/IVF?

The infertile patients with aging ovaries-also sometimes referred to as impending premature ovarian insufficiency (POI), impending premature ovarian failure (POF), or poor ovarian responders (POR), constitute a significant and increasing bulk of the patients appealing to IVF/ART. Different causes have been cited in the literature, among the identified etiologies, including chromosomal and genetic etiology, metabolic, enzymatic, iatrogenic, toxic, autoimmune, and infectious causes. Although the most successful and ultimate treatment of POI/POF/POR patients is egg donation (ED), many, if not most, of these infertile women are reluctant to consent to ED upon the initial diagnostic interview, requesting alternative solutions despite the low odds for success. Despite anecdotal case reports, no unequivocal treatment proved to be successful for these patients in prospective randomized controlled trials. Nevertheless, the addition of growth hormone (GH) to ovarian stimulation in POR with GH deficiency may improve the results of controlled ovarian hyperstimulation (COH) and the IVF success. In patients with autoimmune etiology for POR/POI, the combination of glucocorticosteroids, pituitary-ovarian suppression, and COH may be successful in achieving the desired conception.

Biological and Clinical Rationale for Androgen Priming in Ovarian Stimulation

Androgen receptors are expressed by all stages of growing follicles, and follicular fluid androgen levels are positively correlated to granulosa cell androgen receptor and follicle-stimulating hormone (FSH) receptor expression. Thus, androgens may promote follicular growth, accumulation and/or responsiveness to gonadotropins. This is explored therapeutically in the concept of androgen priming, to improve the ovarian response to stimulation in assisted reproduction. Androgen effects may be achieved in two different ways, either directly by providing exogenous androgen or by providing luteinizing hormone (LH) activity [i.e., LH or human chorionic gonadotropin (hCG)] to stimulate local ovarian production of androgen. The androgen concentrations in follicular fluid by far exceed the levels in female circulation and it has recently been shown that there was no correlation between serum testosterone levels and follicular fluid androgen levels. There is some evidence that administration of exogenous dehydroepiandrosterone or testosterone increases live birth rates, but an optimal protocol has not been established and such adjuvant treatment should be considered experimental. Furthermore, studies exploring long-term administration of LH activity, achieving LH levels comparable to those seen in women with polycystic ovary syndrome, are awaited. The aim of the present review is to discuss critically the most suitable approach for androgen priming from a biological and clinical standpoint, and to evaluate current approaches and results obtained in clinical trials.