Fetal programming: prenatal testosterone treatment causes intrauterine growth retardation, reduces ovarian reserve and increases ovarian follicular recruitment

Effects of maternal poor ovarian response on the reproductive endocrine profiles of the next generation: a prospective cohort study in China

STUDY QUESTION

Do offspring born to mothers with poor ovarian response (POR) have alterations in their reproductive endocrine profile at 2-6 years of age compared to those born to mothers with normal ovarian response?

SUMMARY ANSWER

Female offspring born to young mothers (<35 years) with expected POR were more likely to have low serum anti-Müllerian hormone (AMH) levels in childhood.

WHAT IS KNOWN ALREADY

POR affects 32-43% of women in infertility clinics. Genetic susceptibility and potentially adverse intrauterine environments pose threats to the next generation. However, there is currently no direct evidence of intergenerational reproductive effects associated with POR.

STUDY DESIGN SIZE DURATION

We conducted a prospective cohort study to investigate the intergenerational effects of maternal POR on reproductive endocrine health of offspring. Data were obtained from 'Assisted Reproductive Technology-born KIDs (ARTKID)', a birth cohort established in 2013 at a tertiary care center in China. A total of 3103 offspring, aged 2-6, born between 2013 and 2019, were recruited and included in our study until 2021. The exposed offspring conceived by ART were classified into four groups based on their mothers' categorization using the Patient-Oriented Strategies Encompassing IndividualizeD Oocyte Number (POSEIDON) criteria. The unexposed offspring were born to mothers with normal ovarian response after ART.

PARTICIPANTS/MATERIALS SETTING METHODS

Offspring conceived by ART provided blood samples at 2-6 years for the assessment of reproductive endocrine parameters. Mean difference and 95% CI were obtained based on a linear mixed model. The adjusted model accounted for paternal age, maternal age, offspring age, paternal smoking, use of ICSI, and frozen embryo transfer.

MAIN RESULTS AND THE ROLE OF CHANCE

Female offspring born to young mothers with expected POR (POSEIDON Group 3) had lower AMH and PRL (prolactin) levels in childhood compared to controls (AMH: adjusted mean difference [AMD] = -0.64, 95% CI = -1.10, -0.18; PRL: AMD = -1.59, 95% CI = -2.97, -0.21). Female offspring born to older mothers (≥35 years) with expected POR (POSEIDON Group 4) showed a decreasing trend in AMH levels, though this difference was not statistically significant compared to controls [AMD = -0.60, 95% CI = -1.31, -0.12]. Female offspring born to young mothers with unexpected POR (POSEIDON Group 1) had lower DHEA-S (dehydroepiandrosterone sulfate) levels than controls [AMD = -1.38, 95% CI = -2.58, -0.17]. In contrast, male offspring born to POR mothers showed similar reproductive endocrine profiles as controls.

LIMITATIONS REASONS FOR CAUTION

The offspring were aged 2-6 years, limiting the ability to assess comprehensive reproductive phenotypic changes. Longer follow-up studies are necessary.

WIDER IMPLICATIONS OF THE FINDINGS

The potential effects of maternal POR on reproductive endocrine profiles of offspring may be primarily linked to ovarian reserve. Genetic susceptibility, hypoandrogenism, and other intrauterine environmental factors may be probable explanations for reduction in AMH levels observed in female offspring born to young mothers with expected POR.

STUDY FUNDING/COMPETING INTERESTS

This study was supported by the National Key Research and Development Program of China (2022YFC2703000, 2022YFC2704404, 2024YFC2706902, 2022YFC2702905, 2024YFC2706700), CAMS Innovation Fund for Medical Sciences (2021-I2M-5-001), Shandong Provincial Natural Science Foundation (ZR2022JQ33), the Fundamental Research Funds of Shandong University (2023QNTD004), the National Special Support Program for High-level Talents, the Health Science and Technology Innovation Team Construction Project of Shandong Province, and the Taishan Scholars Program for Young Experts of Shandong Province (tsqn201909195). The authors declare that they have no competing interests.

TRIAL REGISTRATION NUMBER

N/A.

Disrupting Amh and androgen signaling reveals their distinct roles in zebrafish gonadal differentiation and gametogenesis

Sex determination and differentiation in zebrafish involve a complex interaction of male and female-promoting factors. While Dmrt1 has been established as a critical male-promoting factor, the roles of Anti-Müllerian hormone (Amh) and androgen signaling remain less clear. This study employed an estrogen-deficient zebrafish model (cyp19a1a-/-) to dissect individual and combined roles of Amh and androgen receptor (Ar) signaling in gonadal differentiation and gametogenesis. Loss of amh, but not ar, could rescue all-male phenotype of cyp19a1a-/-, leading to female or intersex, confirming the role of Amh in promoting male differentiation. This rescue was recapitulated in bmpr2a-/- but not bmpr2b-/-, supporting Bmpr2a as the type II receptor for Amh in zebrafish. Interestingly, while disruption of amh or ar had delayed spermatogenesis, the double mutant (amh-/-;ar-/-) exhibited severely impaired spermatogenesis, highlighting their compensatory roles. While Amh deficiency led to testis hypertrophy, likely involving a compensatory increase in Ar signaling, Ar deficiency resulted in reduced hypertrophy in double mutant males. Furthermore, phenotype analysis of triple mutant (amh-/-;ar-/-;cyp19a1a-/-) provided evidence that Ar participated in early follicle development. This study provides novel insights into complex interplay between Amh and androgen signaling in zebrafish sex differentiation and gametogenesis, highlighting their distinct but cooperative roles in male development.

Guidelines for sex-specific considerations to improve rigor in renal research and how we got there

Biological sex significantly influences disease presentation, progression, and therapeutic outcomes in chronic kidney disease and acute kidney injury. Sex hormones, including estrogen and testosterone, modulate key renal functions, including renal blood flow, glomerular filtration, and electrolyte transport, thereby affecting disease trajectory in a sex-specific manner. It is critical for researchers to understand why and how to integrate sex as a biological variable in data collection, analysis, and reporting. Integrating a sex-based perspective in kidney research will lead to more personalized and efficacious treatment strategies, optimizing therapeutic interventions for each sex. If addressed properly, the incorporation of sex as a biological variable (SABV) in renal research not only enhances the mechanistic understanding of renal disease, but also paves the way for precision medicine, promising improved clinical outcomes, and tailored treatment protocols for all patients. This paper is designed to serve as a guideline for researchers interested in rigorously incorporating sex as a biological variable in their studies.

Elevated gestational testosterone impacts vascular and uteroplacental function

Maternal vascular adaptations to establish an adequate blood supply to the uterus and placenta are essential for optimal nutrient and oxygen delivery to the developing fetus in eutherian mammals, including humans. Numerous factors contribute to maintaining appropriate hemodynamics and placental vascular development throughout pregnancy. Failure to achieve or sustain these pregnancy-associated changes in women is strongly associated with an increased risk of antenatal complications, such as preeclampsia, a hypertensive disorder of pregnancy. The precise etiology of preeclampsia is unknown, but emerging evidence points to a potential role for androgens. The association between androgens and maternal cardiovascular and placental function merits particular attention due to the notable 2- to 3-fold elevated plasma testosterone (T) levels observed in preeclampsia. T levels in preeclamptic women positively correlate with vascular dysfunction, and preeclampsia is associated with increased androgen receptor (AR) levels in placental tissues. Moreover, animal studies replicating the pattern and magnitude of T increase observed in preeclamptic pregnancies have reproduced key features of preeclampsia, including gestational hypertension, endothelial dysfunction, heightened vasoconstriction to angiotensin II, impaired spiral artery remodeling, placental hypoxia, reduced nutrient transport, and fetal growth restriction. Collectively, these findings suggest that AR-mediated activity plays a significant role in the clinical presentation of preeclampsia. This review critically evaluates this hypothesis, considering both clinical and preclinical evidence.

Early- to mid-gestational testosterone excess leads to adverse cardiac outcomes in postpartum sheep

Cardiovascular dysfunctions complicate 10-20% of pregnancies, increasing the risk for postpartum mortality. Various gestational insults, including preeclampsia are reported to be associated with adverse maternal cardiovascular outcomes. One such insult, gestational hyperandrogenism increases the risk for preeclampsia and other gestational morbidities but its impact on postpartum maternal health is not well known. We hypothesize that gestational hyperandrogenism such as testosterone (T) excess will adversely impact the maternal heart in the postpartum period. Pregnant ewes were injected with T propionate from day 30 to day 90 of gestation (term 147 days). Three months postpartum, echocardiograms, plasma cytokine profiles, cardiac morphometric, and molecular analysis were conducted [control (C) n = 6, T-treated (T) n = 7 number of animals]. Data were analyzed by two-tailed Student's t test and Cohen's effect size (d) analysis. There was a nonsignificant large magnitude decrease in cardiac output (7.64 ± 1.27 L/min vs. 10.19 ± 1.40, P = 0.22, d = 0.81) and fractional shortening in the T ewes compared with C (35.83 ± 2.33% vs. 41.50 ± 2.84, P = 0.15, d = 0.89). T treatment significantly increased 1) left ventricle (LV) weight-to-body weight ratio (2.82 ± 0.14 g/kg vs. 2.46 ± 0.08) and LV thickness (14.56 ± 0.52 mm vs. 12.50 ± 0.75), 2) proinflammatory marker [tumor necrosis factor-alpha (TNF-α)] in LV (1.66 ± 0.35 vs. 1.06 ± 0.18), 3) LV collagen (Masson's Trichrome stain: 3.38 ± 0.35 vs. 1.49 ± 0.15 and Picrosirius red stain: 5.50 ± 0.32 vs. 3.01 ± 0.23), 4) markers of LV apoptosis, including TUNEL (8.3 ± 1.1 vs. 0.9 ± 0.18), bcl-2-associated X protein (Bax)+-to-b-cell lymphoma 2 (Bcl2)+ ratio (0.68 ± 0.30 vs. 0.13 ± 0.02), and cleaved caspase 3 (15.4 ± 1.7 vs. 4.4 ± 0.38). These findings suggest that gestational testosterone excess adversely programs the maternal LV, leading to adverse structural and functional consequences in the postpartum period.NEW & NOTEWORTHY Using a sheep model of human translational relevance, this study provides evidence that excess gestational testosterone exposure such as that seen in hyperandrogenic disorders adversely impacts postpartum maternal hearts.

Serum anti-mullerian hormone, sex hormone, and nutrient levels in reproductive age women with celiac disease

PURPOSE

This study aimed to investigate the changes in serum Anti-Müllerian Hormone (AMH) levels, sex hormone levels, follicle-stimulating hormone (FSH)/luteinizing hormone (LH) ratio in patients with celiac disease (CeD), and their correlation with clinical characteristics and nutrient levels.

METHODS

This cross-sectional study collected clinical and biochemical data from a total of 67 females diagnosed with CeD and 67 healthy females within the reproductive age range of 18-44 years. The study was conducted at a tertiary hospital between September 2016 and January 2024. Both groups underwent comprehensive clinical and laboratory assessments. Serum levels of AMH and sex hormones were quantified using chemiluminescence immunoassay, and their associations with CeD clinical features and nutrient levels were thoroughly analyzed.

RESULTS

The study included 67 patients and 67 controls with a mean age of 36.7±7.6 years. No statistically significant differences were found between the two groups in mean age, BMI, FSH, LH, E2, P levels, FSH/LH, menstrual irregularities, abortions history, parity, and gravidity (all P>0.05). However, AMH, T, FER, FA, Zn, and Se levels were significantly lower, and PRL levels were higher in the CeD group (all P<0.05). Spearman's correlation analysis showed that AMH levels were negatively correlated with age, tTG level, disease duration, and Marsh grading (P<0.05).

CONCLUSIONS

This study highlights the association between impaired ovarian function in CeD patients and disease severity and nutrient levels. Early detection and intervention for ovarian function abnormalities are imperative to enhance fertility potential in CeD patients.

Phenotypic and genetic relationships among anogenital distance, anti-Müllerian hormone, and in vitro embryo production in Gyr dairy cattle

Anti-Müllerian hormone (AMH) concentration and number of recovered oocytes (ROOC) are phenotypic parameters associated with in vitro embryo production (IVEP). More recently, anogenital distance (AGD) has been proposed as a proxy for fertility in dairy cattle that is easy to collect at a low cost. The aim of this study was to characterize the AGD and its phenotypic and genetic associations with AMH and IVEP in Bos indicus Gyr dairy cattle. The hypothesis was that the number of ROOC, in vitro-produced embryos, and AMH concentration would increase as the AGD decreases. From July to December 2021, a single morphometrical measurement of AGD was collected in 552 donors from 6 herds in Brazil. A subset of donors had AMH assayed on the same day. Only ovum pick-up events that occurred up to 12 mo preceding and 7 mo succeeding the AGD measurement were used to assess the association between AGD, AMH, and IVEP. Thus, 472 donors (1,551 ovum pick-up events and 140 donors with AMH) were considered in the analysis. A raw average was calculated for each individual donor's ROOC, viable oocytes, total produced embryos, viability rate, and embryo rate (defined as total produced embryos/viable oocytes). Comparisons were conducted within the age categories of 3 to <6 yr or 6 to <10 yr. Phenotypic associations were performed in SAS software (SAS Institute Inc., Cary, NC). Genetic correlations were estimated using the BLUPF90 family of programs. The AGD (128.7 mm ± 14; mean ± standard deviation) had a normal distribution and was highly variable (83 to 172 mm) among the Gyr population. Our experimental hypothesis was partially supported by a phenotypic association of a greater number of total produced embryos (R2 = 0.023) as AGD decreased. Our results failed to support an increase in AMH concentration along with a decrease in AGD. In addition, positive and low genetic correlations were observed between AGD and viable oocytes (r = 0.08), and embryo rate (r = 0.20). A greater number of viable oocytes and embryos were observed in donors in the high compared with intermediate and low ROOC categories within both age categories. The age interval of 3 to <6 yr showed a greater number of recovered and viable oocytes for the high AMH compared with the low category, but no differences were observed among the AGD categories. In summary, for the Gyr breed, AGD was phenotypically inversely associated with a quantity-related parameter, such as the total number of produced embryos. In contrast, AGD showed a low genetic correlation with qualitative-related outcomes such as viable oocytes and embryo rate. Further studies should be performed to validate these retrospective analyses and to better understand the association between AGD and IVEP.

Gestational testosterone excess early to mid-pregnancy disrupts maternal lipid homeostasis and activates biosynthesis of phosphoinositides and phosphatidylethanolamines in sheep

Gestational hyperandrogenism is a risk factor for adverse maternal and offspring outcomes with effects likely mediated in part via disruptions in maternal lipid homeostasis. Using a translationally relevant sheep model of gestational testosterone (T) excess that manifests maternal hyperinsulinemia, intrauterine growth restriction (IUGR), and adverse offspring cardiometabolic outcomes, we tested if gestational T excess disrupts maternal lipidome. Dimensionality reduction models following shotgun lipidomics of gestational day 127.1 ± 5.3 (term 147 days) plasma revealed clear differences between control and T-treated sheep. Lipid signatures of gestational T-treated sheep included higher phosphoinositides (PI 36:2, 39:4) and lower acylcarnitines (CAR 16:0, 18:0, 18:1), phosphatidylcholines (PC 38:4, 40:5) and fatty acids (linoleic, arachidonic, Oleic). Gestational T excess activated phosphatidylethanolamines (PE) and PI biosynthesis. The reduction in key fatty acids may underlie IUGR and activated PI for the maternal hyperinsulinemia evidenced in this model. Maternal circulatory lipids contributing to adverse cardiometabolic outcomes are modifiable by dietary interventions.

Sex-Specific Perturbation of Systemic Lipidomic Profile in Newborn Lambs Impacted by Prenatal Testosterone Excess

Gestational hyperandrogenism adversely impacts offspring health. Using an ovine model, we found that prenatal testosterone (T) excess adversely affects growth and cardiometabolic outcomes in female offspring and produces sex-specific effects on fetal myocardium. Since lipids are essential to cardiometabolic function, we hypothesized that prenatal T excess leads to sex-specific disruptions in lipid metabolism at birth. Shotgun lipidomics was performed on the plasma samples collected 48 hours after birth from female (F) and male (M) lambs of control (C) and (T) sheep (CF = 4, TF = 7, CM = 5, TM = 10) and data were analyzed by univariate analysis, multivariate dimensionality reduction modeling followed by functional enrichment, and pathway analyses. Biosynthesis of phosphatidylserine was the major pathway responsible for sex differences in controls. Unsupervised and supervised models showed separation between C and T in both sexes with glycerophospholipids and glycerolipids classes being responsible for the sex differences between C and T. T excess increased cholesterol in females while decreasing phosphatidylcholine levels in male lambs. Specifically, T excess: 1) suppressed the phosphatidylethanolamine N-methyltransferase (PEMT) phosphatidylcholine synthesis pathway overall and in TM lambs as opposed to suppression of carnitine levels overall and TF lambs; and 2) activated biosynthesis of ether-linked (O-)phosphatidylethanolamine and O-phosphatidylcholine from O-diacylglycerol overall and in TF lambs. Higher cholesterol levels could underlie adverse cardiometabolic outcomes in TF lambs, whereas suppressed PEMT pathway in TM lambs could lead to endoplasmic reticulum stress and defective lipid transport. These novel findings point to sex-specific effects of prenatal T excess on lipid metabolism in newborn lambs, a precocial ovine model of translational relevance.

In vitro fertilization outcomes in a mouse model of gender-affirming hormone therapy in transmasculine youth

OBJECTIVE

To investigate in vitro fertilization (IVF) outcomes in an adolescent transmasculine mouse model mimicking gender-affirming hormone therapy in prepubertal youth, both on testosterone (T) and after T washout.

DESIGN

Experimental laboratory study using a validated mouse model.

SETTING

University-based basic science research laboratory.

ANIMAL(S)

A total of 80 prepubertal 26-day-old C57BL/6N female mice were used in this study.

INTERVENTION(S)

Animals (n = 10/group) were implanted subcutaneously with gonadotropin-releasing hormone agonist at 3.6 mg or received sham surgery. After 21 days, they were implanted with silastic tubing containing either T 10 mg or placebo for 6 weeks. After 6 weeks, a group of animals were superovulated for immediate IVF, and another group had the implant removed and went through superovulation for IVF after 2 weeks (washout IVF). The total number of oocytes yielded, oocyte maturity rate, fertilization rate, and numbers of 2-cell embryos, 4-8-cell embryos, morula, blastocysts, and hatching blastocysts were recorded.

RESULT(S)

Testosterone treatment negatively impacted IVF outcomes in animals stimulated when receiving T, but not after T washout. Pretreatment with gonadotropin-releasing hormone agonist did not affect IVF outcomes.

CONCLUSION(S)

Although current T had a negative impact on IVF outcomes compared with controls, animals were still able to produce viable oocytes for fertilization and develop into blastocysts. Future efforts to study the impact of long-term T exposure on oocyte quality, especially aneuploidy rates, pregnancy outcomes, and live birth rates, are necessary.

Potential factors result in diminished ovarian reserve: a comprehensive review

The ovarian reserve is defined as the quantity of oocytes stored in the ovary or the number of oocytes that can be recruited. Ovarian reserve can be affected by many factors, including hormones, metabolites, initial ovarian reserve, environmental problems, diseases, and medications, among others. With the trend of postponing of pregnancy in modern society, diminished ovarian reserve (DOR) has become one of the most common challenges in current clinical reproductive medicine. Attributed to its unclear mechanism and complex clinical features, it is difficult for physicians to administer targeted treatment. This review focuses on the factors associated with ovarian reserve and discusses the potential influences and pathogenic factors that may explain the possible mechanisms of DOR, which can be improved or built upon by subsequent researchers to verify, replicate, and establish further study findings, as well as for scientists to find new treatments.

Placental assessment using spectral analysis of the envelope of umbilical venous waveforms in sheep

INTRODUCTION

This study was designed to test the efficacy of an ultrasound flow measurement method to evaluate placental function in a hyperandrogenic sheep model that produces placental morphologic changes and an intrauterine growth restriction (IUGR) phenotype.

MATERIALS AND METHODS

Pregnant ewes were assigned randomly between control (n = 12) and testosterone-treatment (T-treated, n = 22) groups. The T-treated group was injected twice weekly intramuscularly (IM) with 100 mg testosterone propionate. Control sheep were injected with corn oil vehicle. Lambs were delivered at 119.5 ± 0.48 days gestation. At the time of delivery of each lamb, flow spectra were generated from one fetal artery and two fetal veins, and the spectral envelopes examined using fast Fourier transform analysis. Base 10 logarithms of the ratio of the amplitudes of the maternal and fetal spectral peaks (LRSP) in the venous power spectrum were compared in the T-treated and control populations. In addition, we calculated the resistive index (RI) for the artery defined as ((peak systole - min diastole)/peak systole). Two-tailed T-tests were used for comparisons.

RESULTS

LRSPs, after removal of significant outliers, were -0.158 ± 0.238 for T-treated and 0.057 ± 0.213 for control (p = 0.015) animals. RIs for the T-treated sheep fetuses were 0.506 ± 0.137 and 0.497 ± 0.086 for controls (p = 0.792) DISCUSSION: LRSP analysis distinguishes between T-treated and control sheep, whereas RIs do not. LRSP has the potential to identify compromised pregnancies.

Sex bias in utero alters ovarian reserve but not uterine capacity in female offspring†

Environmental stressors to which a fetus is exposed affect a range of physiological functions in postnatal offspring. We aimed to determine the in utero effect of steroid hormones on the reproductive potential of female offspring using a porcine model. Reproductive tracts of pigs from female-biased (>65% female, n = 15), non-biased (45-54.9% female, n = 15), and male-biased litters (<35% females, n = 9) were collected at slaughter (95-115 kg). Ovaries and uterine horns were processed for H&E or immunohistochemistry. Variability of data within groups was analyzed with a Levene's test, while data were analyzed using mixed linear models in R. In the ovarian reserve, there was a significant birth weight by sex ratio interaction (P = 0.015), with low birth weight pigs from male-biased litters having higher numbers of primordial follicles with opposite trends seen in pigs from female-biased litters. Sex bias held no effect on endometrial gland development. A lower birth weight decreased the proportion of glands found in the endometrium (P = 0.045) and was more variable in both male-biased and female-biased litters (P = 0.026). The variability of primordial follicles from male-biased litters was greater than non- and female-biased litters (P = 0.014). Similarly, endometrial stromal nuclei had a greater range in male- and female-biased litters than non-biased litters (P = 0.028). A crucial finding was the greater variability in primordial follicles in the ovaries from females derived from male-biased litters and stromal cell count in the endometrium of females from male- and female-biased litters. This could be inflating the variability of reproductive success seen in females from male-biased litters.

Cardiovascular disease risk in offspring of polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is the most common endocrine disorder affecting women at reproductive age. PCOS diagnosis (Rotterdam criteria) is based on the presence of two out of three criteria; clinical and/or biochemical hyperandrogenism, oligo- or an-ovulation and polycystic ovaries. PCOS women suffer from a constellation of reproductive and metabolic abnormalities including obesity and insulin resistance. PCOS women also have increased blood pressure and increased risk of cardiovascular diseases (CVD). In-utero, offspring of PCOS women are exposed to altered maternal hormonal environment and maternal obesity (for most of PCOS women). Offspring of PCOS women could also be subject to genetic susceptibility, the transgenerational transmission of some of the PCOS traits or epigenetic changes. Offspring of PCOS women are commonly reported to have an abnormal birth weight, which is also a risk factor for developing CVD and hypertension later in life. Although studies have focused on the growth pattern, reproductive and metabolic health of children of PCOS women, very limited number of studies have addressed the risk of hypertension and CVD in those offspring particularly as they age. The current narrative review is designed to summarize the available literature (both human studies and experimental animal studies) and highlight the gaps in addressing hypertension and CVD risks in offspring of PCOS women or hyperandrogenemic female animal models.

Maternal Testosterone and Offspring Birth Weight: A Mendelian Randomization Study

CONTEXT

Evidence has shown maternal androgen levels in both the general population and populations with hyperandrogenic disorders are inversely associated with offspring birth weight.

CONTEXT

We aimed to investigate the causal effect of maternal testosterone levels in the general population on offspring birth weight and preterm delivery risk using a two-sample Mendelian randomization (MR) method.

METHODS

We obtained independent genetic instruments from a sex-specific genome-wide association study with up to 230 454 females of European descent from the UK Biobank. Genetic instruments with consistent testosterone effects but no aggregate effect on sex hormone-binding globulin were used to perform the main analysis. Summary-level data of offspring birth weight adjusted for genotype were obtained from a study with 210 406 females of European descent. Summary-level data of preterm delivery were obtained from the FinnGen study (6736 cases and 116 219 controls).

RESULTS

MR analysis showed that each SD (0.62 nmol/L) increase in testosterone levels could reduce the offspring birth weight by 37.26 g (95% CI, 19.59-54.94 g; P = 3.62 × 10-5). Each SD increase in testosterone levels was also associated with an increased risk of preterm delivery (odds ratio = 1.329; 95% CI, 1.161-1.520; P = 3.57 × 10-5). Similar results were found using different MR methods and multivariable MR analyses.

CONCLUSION

This two-sample MR study showed genetically determined higher circulating testosterone levels in females from the general population were associated with low birth weight of offspring and increased risk of preterm delivery.

Somatic cell fate maintenance in mouse fetal testes via autocrine/paracrine action of AMH and activin B

Fate determination and maintenance of fetal testes in most mammals occur cell autonomously as a result of the action of key transcription factors in Sertoli cells. However, the cases of freemartin, where an XX twin develops testis structures under the influence of an XY twin, imply that hormonal factor(s) from the XY embryo contribute to sex reversal of the XX twin. Here we show that in mouse XY embryos, Sertoli cell-derived anti-Mullerian hormone (AMH) and activin B together maintain Sertoli cell identity. Sertoli cells in the gonadal poles of XY embryos lacking both AMH and activin B transdifferentiate into their female counterpart granulosa cells, leading to ovotestis formation. The ovotestes remain to adulthood and produce both sperm and oocytes, although there are few of the former and the latter fail to mature. Finally, the ability of XY mice to masculinize ovaries is lost in the absence of these two factors. These results provide insight into fate maintenance of fetal testes through the action of putative freemartin factors.

Associations of maternal anthropometrics with newborn anogenital distance and the 2:4 digit ratio

STUDY QUESTION

Are maternal anthropometrics associated with anogenital distance (AGD) and 2:4 digit ratio (2:4D) in newborns?

SUMMARY ANSWER

Select maternal anthropometrics indicative of obesity or increased adiposity are associated with elongated AGD in daughters.

WHAT IS KNOWN ALREADY

Excessive maternal weight or adiposity before or in early pregnancy may impact child reproductive, and other hormonally mediated, development. AGD and 2:4D are proposed markers of in utero reproductive development.

STUDY DESIGN, SIZE, DURATION

This study includes 450 mother/newborn dyads participating in the Illinois Kids Development Study (I-KIDS), a prospective pregnancy cohort from Champaign-Urbana, IL, USA. Participants included in the current study enrolled between 2013 and 2018.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Most mothers in this study were college-educated (82%) and non-Hispanic White (80%), and 55% were under- or normal weight before pregnancy. Pregnant women aged 18-40 years reported pre-pregnancy weight and height to calculate pre-pregnancy BMI. At 8-15 weeks gestation, we measured waist and hip circumference, and evaluated weight, % body fat, visceral fat level, % muscle and BMI using bioelectrical impedance analysis. Within 24 h of birth, we measured newborn 2nd and 4th left/right digits to calculate the 2:4D. In daughters, we measured AGDAF (anus to fourchette) and AGDAC (anus to clitoris). In sons, we measured AGDAS (anus to scrotum) and AGDAP (anus to base of the penis).

MAIN RESULTS AND THE ROLE OF CHANCE

Select maternal anthropometrics were positively associated with AGD in newborn daughters, but not sons. For example, AGDAC was 0.73 mm (95% CI: 0.15, 1.32) longer for every interquartile range (IQR) increase in pre-pregnancy BMI and 0.88 mm (95% CI: 0.18, 1.58) longer for every IQR increase in hip circumference, whereas AGDAF was 0.51 mm (95% CI: 0.03, 1.00) and 0.56 mm (95% CI: 0.03, 1.09) longer for every IQR increase in hip and waist circumference, respectively. Quartile analyses generally supported linear associations, but additional strong associations emerged in Q4 (versus Q1) of maternal % body fat and visceral fat levels with AGDAC. In quartile analyses, we observed only a few modest associations of maternal anthropometrics with 2:4D, which differed by hand (left versus right) and newborn sex. Although there is always the possibility of spurious findings, the associations for both measures of female AGD were consistent across multiple maternal anthropometric measures, which strengthens our conclusions.

LIMITATIONS, REASONS FOR CAUTION

Our study sample was racially and ethnically homogenous, educated and relatively healthy, so our study may not be generalizable to other populations. Additionally, we may not have been powered to identify some sex-specific associations, especially for 2:4D.

WIDER IMPLICATIONS OF THE FINDINGS

Increased maternal weight and adiposity before and in early pregnancy may lengthen the female AGD, which warrants further investigation.

STUDY FUNDING/COMPETING INTEREST(S)

This publication was made possible by the National Institute for Environmental Health Sciences (NIH/NIEHS) grants ES024795 and ES022848, the National Institute of Child Health and Human Development grant R03HD100775, the U.S. Environmental Protection Agency grant RD83543401 and National Institute of Health Office of the Director grant OD023272. Its contents are solely the responsibility of the grantee and do not necessarily represent the official views of the US EPA or NIH. Furthermore, the US EPA does not endorse the purchase of any commercial products or services mentioned in the publication. This project was also supported by the USDA National Institute of Food and Agriculture and Michigan AgBioResearch. The authors declare no competing interests.

TRIAL REGISTRATION NUMBER

N/A.

Maternal Exposure to D-galactose Reduces Ovarian Reserve in Female Rat Offspring Later in Life

BACKGROUND

Embryonic life is critical for the formation of ovaries in mammals, and the intrauterine environment may affect ovarian reserve.

OBJECTIVES

The present study aimed to investigate the impact of prenatal D-galactose exposure on ovarian reserve in female rat offspring in their later lives.

METHODS

Ten pregnant Wistar rats were randomly divided into two groups. In one group, rats were fed with 35% D-galactose-enriched food from the third day to the end of pregnancy, and in the other group, rats were fed with a standard diet throughout pregnancy. Female offspring (prenatally galactose-exposed rats and non-exposed control rats) were examined in terms of hormonal levels [anti-Mullerian hormones (AMH), follicle-stimulating hormone (FSH), and estradiol (E2)] and ovarian histology at 45 - 50, 105 - 110, and 180 - 185 days of their age.

RESULTS

The number of primordial follicles significantly decreased time-dependently in prenatally galactose-exposed rats compared to controls (P-value = 0.002). In addition, decreases in AMH (3.25 vs. 7.5 ng/mL; P = 0.000) and E2 (7.9 vs. 19.5 pg/mL; P = 0.000) and increases in FSH (6.5 vs. 0.8 mIU/mL; P < 0.007) were observed in galactose-exposed rats compared to controls at 45 - 50 days of age.

CONCLUSIONS

Prenatal exposure to D-galactose negatively affects ovarian reserve in female rats in their later lives. However, further investigation is needed to confirm our findings and explore underlying mechanisms.

Characterization of micro-RNA in women with different ovarian reserve

Women undergoing infertility treatment are routinely subjected to one or more tests of ovarian reserve. Therefore, an adequate assessment of the ovarian reserve is necessary for the treatment. In this study, we aimed to characterize the potential role of microRNAs (miRNAs) as biomarkers for women with different ovarian reserves. A total of 159 women were recruited in the study and classified according to their anti-Müllerian hormone (AMH) level into three groups: (1) low ovarian reserve (LAMH, n = 39), (2) normal ovarian reserve (NAMH, n = 80), and (3) high ovarian reserve (HAMH, n = 40). SurePrint Human miRNA array screening and reverse transcription-quantitative PCR (RT-qPCR) were respectively employed to screen and validate the miRNA abundance level in the three tested groups. Compared with NAMH, the abundance level of 34 and 98 miRNAs was found to be significantly altered in LAMH and HAMH, respectively. The abundance level of miRNAs was further validated by RT-qPCR in both, the screening samples as well as in an independent set of validation samples. The abundance levels of the validated miRNAs were significantly correlated with the AMH level. The best AUC value for the prediction of the increase and decrease in the AMH level was obtained for the miR-100-5p and miR-21-5p, respectively. The level of miRNAs abundance correlates with the level of AMH, which may serve as a tool for identifying women with a different ovarian reserve and may help to lay the ground for the development of novel diagnostic approaches.

Polycystic Ovary Syndrome: the Epigenetics Behind the Disease

Polycystic ovary syndrome (PCOS) is one of the most common endocrine disorders, affecting approximately 5-20% of women of reproductive age. PCOS is a multifactorial, complex, and heterogeneous disease, characterized by hyperandrogenism, ovulatory dysfunction, and polycystic ovaries, which may lead to impaired fertility. Besides the reproductive outcomes, multiple comorbidities, such as metabolic disturbances, insulin resistance, obesity, diabetes, and cardiovascular disease, are associated with PCOS. In addition to the clear genetic basis, epigenetic alterations may also play a central role in PCOS outcomes, as environmental and hormonal alterations directly affect clinical manifestations and PCOS development. Here, we highlighted the epigenetic modifications in the multiplicity of clinical manifestations, as well as environmental epigenetic disruptors, as intrauterine hormonal and metabolic alterations affecting embryo development and the adulthood lifestyle, which may contribute to PCOS development. Additionally, we also discussed the new approaches for future studies and potential epigenetic biomarkers for the treatment of associated comorbidities and improvement in quality of life of women with PCOS.

Sex-dependent associations of maternal androgen levels with offspring BMI and weight trajectory from birth to early childhood

CONTEXT

In preclinical studies, high androgen levels during pregnancy are associated with low birth weight and rapid postnatal weight gain in the offspring. However, human data linking prenatal androgens with birth weight and early life weight gain in the offspring are scarce.

DESIGN

We evaluated 516 mother-child pairs enrolled in the New England birth cohorts of the Collaborative Perinatal Project (1959-1966). We assayed androgen bioactivity in maternal sera during third-trimester using a receptor-mediated luciferase expression bioassay. Age and sex-specific BMI Z-scores (BMIz), defined using established standards, were assessed at birth, 4 months, 1 year, 4 years, and 7 years. We used linear mixed models to evaluate the relation of maternal androgens with childhood BMIz overall and by sex. We examined the association of maternal androgens with fetal growth restriction. The association of weight trajectories with maternal androgens was examined using multinomial logistic regression.

RESULTS

Higher maternal androgen levels associated with lower BMIz at birth (β = - 0.39, 95% CI: - 0.73, - 0.06); this relation was sex-dependent, such that maternal androgens significantly associated with BMIz at birth in girls alone (β = - 0.72, 95% CI: - 1.40, - 0.04). The relation of maternal androgens with fetal growth restriction revealed dose threshold effects that differed by sex. There was no significant association between maternal androgens and weight trajectory overall. However, we found a significant sex interaction (p = 0.01); higher maternal androgen levels associated with accelerated catch-up growth in boys (aOR = 2.14, 95% CI: 1.14, 4.03).

CONCLUSION

Our findings provide evidence that maternal androgens may have differential effects on the programming of intrauterine growth and postnatal weight gain depending on fetal sex.

Minipuberty: Looking Back to Understand Moving Forward

Hypothalamic-pituitary-gonadal (HPG) axis activation occurs three times in life: the first is during fetal life, and has a crucial role in sex determination, the second time is during the first postnatal months of life, and the third is with the onset of puberty. These windows of activation recall the three windows of the "Developmental Origin of Health and Disease" (DOHaD) paradigm and may play a substantial role in several aspects of human development, such as growth, behavior, and neurodevelopment. From the second trimester of pregnancy there is a peak in gonadotropin levels, followed by a decrease toward term and complete suppression at birth. This is due to the negative feedback of placental estrogens. Studies have shown that in this prenatal HPG axis activation, gonadotropin levels display a sex-related pattern which plays a crucial role in sex differentiation of internal and external genitalia. Soon after birth, there is a new increase in LH, FSH, and sex hormone concentrations, both in males and females, due to HPG re-activation. This postnatal activation is known as "minipuberty." The HPG axis activity in infancy demonstrates a pulsatile pattern with hormone levels similar to those of true puberty. We review the studies on the changes of these hormones in infancy and their influence on several aspects of future development, from linear growth to fertility and neurobehavior.

Developmental programming of the female reproductive system-a review

Exposures to adverse conditions in utero can lead to permanent changes in the structure and function of key physiological systems in the developing fetus, increasing the risk of disease and premature aging in later postnatal life. When considering the systems that could be affected by an adverse gestational environment, the reproductive system of developing female offspring may be particularly important, as changes have the potential to alter both reproductive capacity of the first generation, as well as health of the second generation through changes in the oocyte. The aim of this review is to examine the impact of different adverse intrauterine conditions on the reproductive system of the female offspring. It focuses on the effects of exposure to maternal undernutrition, overnutrition/obesity, hypoxia, smoking, steroid excess, endocrine-disrupting chemicals, and pollutants during gestation and draws on data from human and animal studies to illuminate underlying mechanisms. The available data indeed indicate that adverse gestational environments alter the reproductive physiology of female offspring with consequences for future reproductive capacity. These alterations are mediated via programmed changes in the hypothalamic-pituitary-gonadal axis and the structure and function of reproductive tissues, particularly the ovaries. Reproductive programming may be observed as a change in the timing of puberty onset and menopause/reproductive decline, altered menstrual/estrous cycles, polycystic ovaries, and elevated risk of reproductive tissue cancers. These reproductive outcomes can affect the fertility and fecundity of the female offspring; however, further work is needed to better define the possible impact of these programmed changes on subsequent generations.

Mechanisms of intergenerational transmission of polycystic ovary syndrome

Developmental origins of adult disease (DoHAD) refers to critical gestational ages during human fetal development and beyond when the endocrine metabolic status of the mother can permanently program the physiology and/or morphology of the fetus, modifying its susceptibility to disease after birth. The aim of this review is to address how DoHAD plays an important role in the phenotypic expression of polycystic ovary syndrome (PCOS), the most common endocrinopathy of women characterized by hyperandrogenism, oligo-anovulation and polycystic ovarian morphology. Clinical studies of PCOS women are integrated with findings from relevant animal models to show how intergenerational transmission of these central components of PCOS are programmed through an altered maternal endocrine-metabolic environment that adversely affects the female fetus and long-term offspring health. Prenatal testosterone treatment in monkeys and sheep have been particularly crucial in our understanding of developmental programming of PCOS because organ system differentiation in these species, as in humans, occurs during fetal life. These animal models, along with altricial rodents, produce permanent PCOS-like phenotypes variably characterized by LH hypersecretion from reduced steroid-negative feedback, hyperandrogenism, ovulatory dysfunction, increased adiposity, impaired glucose-insulin homeostasis and other metabolic abnormalities. The review concludes that DoHAD underlies the phenotypic expression of PCOS through an altered maternal endocrine-metabolic environment that can induce epigenetic modifications of fetal genetic susceptibility to PCOS after birth. It calls for improved maternal endocrine-metabolic health of PCOS women to lower their risks of pregnancy-related complications and to potentially reduce intergenerational susceptibility to PCOS and its metabolic derangements in offspring.

Developmental Programming: Sheep Granulosa and Theca Cell-Specific Transcriptional Regulation by Prenatal Testosterone

Prenatal testosterone (T)-treated sheep, similar to polycystic ovarian syndrome women, manifest reduced cyclicity, functional hyperandrogenism, and polycystic ovary (PCO) morphology. The PCO morphology results from increased follicular recruitment and persistence of antral follicles, a consequence of reduced follicular growth and atresia, and is driven by cell-specific gene expression changes that are poorly understood. Therefore, using RNA sequencing, cell-specific transcriptional changes were assessed in laser capture microdissection isolated antral follicular granulosa and theca cells from age 21 months control and prenatal T-treated (100 mg intramuscular twice weekly from gestational day 30 to 90; term: 147 days) sheep. In controls, 3494 genes were differentially expressed between cell types with cell signaling, proliferation, extracellular matrix, immune, and tissue development genes enriched in theca; and mitochondrial, chromosomal, RNA, fatty acid, and cell cycle process genes enriched in granulosa cells. Prenatal T treatment 1) increased gene expression of transforming growth factor β receptor 1 and exosome component 9, and decreased BCL6 corepressor like 1, BCL9 like, and MAPK interacting serine/threonine kinase 2 in both cells, 2) induced differential expression of 92 genes that included increased mitochondrial, ribosome biogenesis, ribonucleoprotein, and ubiquitin, and decreased cell development and extracellular matrix-related pathways in granulosa cells, and 3) induced differential expression of 56 genes that included increased noncoding RNA processing, ribosome biogenesis, and mitochondrial matrix, and decreased transcription factor pathways in theca cells. These data indicate that follicular function is affected by genes involved in transforming growth factor signaling, extracellular matrix, mitochondria, epigenetics, and apoptosis both in a common as well as a cell-specific manner and suggest possible mechanistic pathways for prenatal T treatment-induced PCO morphology in sheep.

Insulin sensitivity in male sheep born to ewes treated with testosterone during pregnancy

In animal models, exposure to excess testosterone during gestation induces polycystic ovary syndrome (PCOS)-like reproductive and metabolic traits in female offspring, suggesting that the hyperandrogenemic intrauterine environment may have a role in the etiology of PCOS. Additionally, few studies have also addressed metabolic and reproductive outcomes in male offspring. In the present study, the intravenous glucose tolerance test (IGTT) was used to assess the insulin-glucose homeostasis at various ages during sexual development in male sheep born to testosterone-treated ewes. To further analyze the programming effect of testosterone on insulin-glucose homeostasis, indexes of insulin sensitivity were assessed in orchidectomized post-pubertal males born to testosterone-treated ewes (Torq-males) and orchidectomized post-puberal controls (Corq-males) before and 48 h after a testosterone injection. There was no difference in insulin sensitivity indexes between males born to testosterone-treated ewes (T-males) and control males born to control ewes (C-males) at 5, 10, 20 and 30 weeks of age, representing the infantile, early and late pre-pubertal, and early post-pubertal stage of sexual development, respectively. In orchidectomized males, basal levels of insulin and glucose were not different between both groups before and after the testosterone injection; however, Torq-males released more insulin before and after T challenge during the first 20 min of the test. Despite this, plasma glucose concentrations were not different in both groups during IVGTT, resulting in an insulin sensitivity index composite similar between groups. We concluded that the effect of prenatal exposure to excess testosterone may reprogram the pancreatic β-cells insulin release in ovine males, with effects more evident in castrated males versus intact males.

Animal Models to Understand the Etiology and Pathophysiology of Polycystic Ovary Syndrome

More than 1 out of 10 women worldwide are diagnosed with polycystic ovary syndrome (PCOS), the leading cause of female reproductive and metabolic dysfunction. Despite its high prevalence, PCOS and its accompanying morbidities are likely underdiagnosed, averaging > 2 years and 3 physicians before women are diagnosed. Although it has been intensively researched, the underlying cause(s) of PCOS have yet to be defined. In order to understand PCOS pathophysiology, its developmental origins, and how to predict and prevent PCOS onset, there is an urgent need for safe and effective markers and treatments. In this review, we detail which animal models are more suitable for contributing to our understanding of the etiology and pathophysiology of PCOS. We summarize and highlight advantages and limitations of hormonal or genetic manipulation of animal models, as well as of naturally occurring PCOS-like females.

The Protective Effect of Testosterone on the Ovarian Reserve During Cyclophosphamide Treatment

Introduction

Cyclophosphamide, which is widely used to treat malignant disease, causes ovarian follicular atresia, which leads to premature ovarian insufficiency. The present study evaluated the protective effect of testosterone in preventing the decline in the ovarian reserve during cyclophosphamide treatment.

Methods

Using the COV434 human granulosa cell line, the protective effect of testosterone against cyclophosphamide was evaluated by immunocytochemistry, Western blotting and an MTS assay. The follicles in mouse ovaries and serum anti-Mullerian hormone were also assessed to evaluate the effects of testosterone.

Results

Testosterone suppressed the decrease in cell viability and apoptosis caused by cyclophosphamide treatment in vitro. In vivo, the number of atretic follicles in the mouse ovary was significantly lower in the testosterone plus cyclophosphamide group than in the cyclophosphamide alone group (p=0.03). The serum anti-Mullerian hormone was significantly higher in the testosterone plus cyclophosphamide group than in the cyclophosphamide alone group (16.2 [9.7–22.6]) vs 11.2 [8.9–12.1], p<0.01). The rate of cleaved Caspase-3 expression in the testosterone plus cyclophosphamide group was lower than that in the cyclophosphamide alone group (28.4% vs 48.6%, p=0.03).

Conclusion

These findings indicated that testosterone has the potential to prevent ovarian damage induced by cyclophosphamide by protecting granulosa cells from cyclophosphamide-induced apoptosis.

Polycystic Ovary Syndrome: Impact of Lipotoxicity on Metabolic and Reproductive Health

Importance

Polycystic ovary syndrome (PCOS) is the most common endocrinopathy of reproductive-aged women. Women with PCOS are at increased risk of developing several metabolic and reproductive abnormalities, including metabolic syndrome. Underlying the combined metabolic and reproductive dysfunction is lipotoxicity, defined as the ectopic deposition of lipid in nonadipose tissue where it induces oxidative stress linked with insulin resistance and inflammation.

Objective

To examine what metabolic components underlie insulin resistance in PCOS, how lipotoxicity through insulin resistance impairs metabolism and reproduction in these women, and why evidence-based, individualized management is essential for their care.

Evidence Acquisition

PubMed search was performed using relevant terms to identify journal articles related to the subject. Relevant textbook chapters were also used.

Results

Polycystic ovary syndrome by Rotterdam criteria represents a complex syndrome of heterogeneous expression with variable adverse metabolic and reproductive implications. Women with classic PCOS are often insulin resistant and at greatest risk of developing metabolic syndrome with preferential fat accumulation and weight gain. Moreover, PCOS women may also have an altered capacity to properly store fat, causing ectopic lipid accumulation in nonadipose tissue, including the ovaries, where it can perpetuate insulin resistance and inflammation and harm the oocyte.

Conclusions and Relevance

A personalized approach to managing PCOS is essential to improve the health of all PCOS women through cost-effective prevention and/or treatment, to minimize the risk of pregnancy complications in those individuals wishing to conceive, and to optimize the long-term health of PCOS women and their offspring.

Prenatal programming by testosterone of follicular theca cell functions in ovary

In mammalian ovaries, the theca layers of growing follicles are critical for maintaining their structural integrity and supporting androgen synthesis. Through combining the postnatal monitoring of ovaries by abdominal magnetic resonance imaging, endocrine profiling, hormonal analysis of the follicular fluid of growing follicles, and transcriptomic analysis of follicular theca cells, we provide evidence that the exposure of ovine fetuses to testosterone excess activates postnatal follicular growth and strongly affects the functions of follicular theca in adulthood. Prenatal exposure to testosterone impaired androgen synthesis in the small antral follicles of adults and affected the expression in their theca cells of a wide array of genes encoding extracellular matrix components, their membrane receptors, and signaling pathways. Most expression changes were uncorrelated with the concentrations of gonadotropins, steroids, and anti-Müllerian hormone in the recent hormonal environment of theca cells, suggesting that these changes rather result from the long-term developmental effects of testosterone on theca cell precursors in fetal ovaries. Disruptions of the extracellular matrix structure and signaling in the follicular theca and ovarian cortex can explain the acceleration of follicle growth through altering the stiffness of ovarian tissue. We propose that these mechanisms participate in the etiology of the polycystic ovarian syndrome, a major reproductive pathology in woman.

Developmental Programming: Prenatal Testosterone Excess on Ovarian SF1/DAX1/FOXO3

Prenatal testosterone (T) excess, partly via androgenic programming, enhances follicular recruitment/persistence in sheep as in women with polycystic ovarian syndrome (PCOS). Decreased anti-Mullerian hormone (AMH) in early growing and increased AMH in antral follicles may underlie enhanced recruitment and persistence, respectively. Changes in AMH may be mediated by steroidogenic factor 1 (SF1), an enhancer of AMH, and dosage-sensitive sex reversal, adrenal hypoplasia critical region, on chromosome X, gene 1 (DAX1), that antagonizes SF1. Another mediator could be forkhead box 03 (FOXO3) which regulates follicular recruitment/atresia. To test if androgen-programmed changes in SF1, DAX1, and FOXO3 proteins contribute to follicular defects in prenatal T-treated sheep, ovaries from control, prenatal T-, and dihydrotestosterone (DHT)-treated (days 30-90 of gestation) animals at fetal day (FD) 90, FD140, and 1 and 2 years-of-age were studied. Prenatal T increased DAX1 in granulosa cells of primordial through large preantral and theca cells of large preantral follicles at FD140 and increased SF1 in the granulosa cells of preantral and antral and theca cells of large preantral follicle at 2 years-of-age. Prenatal T increased FOXO3 only in theca cells of preantral (FD140) and antral (2 years-of-age) follicles. Prenatal DHT increased DAX1 in granulosa cells from small preantral follicles at FD140 while increasing SF1 in granulosa cells from antral follicles at 1 year-of-age. These age-dependent changes in DAX1/SF1 partly via androgen-programming are consistent with changes in AMH and may contribute to the enhanced follicular recruitment/persistence, and multifollicular phenotype of prenatal T-treated females and may be of translational relevance to PCOS.

The influence of maternal androgen excess on the male reproductive axis

Prenatal androgen excess is suspected to contribute to the development of polycystic ovary syndrome (PCOS) in women. Evidence from preclinical female animal models links maternal androgen excess with the development of PCOS-like features and associated alterations in the neuronal network regulating the reproductive axis. There is some evidence suggesting that maternal androgen excess leads to similar reproductive axis disruptions in men, despite the critical role that androgens play in normal sexual differentiation. Here, the specific impact of maternal androgen excess on the male hypothalamic-pituitary-gonadal axis was investigated using a prenatal androgenization protocol in mice shown to model PCOS-like features in females. Reproductive phenotyping of prenatally androgenised male (PNAM) mice revealed no discernible impact of maternal androgen excess at any level of the reproductive axis. Luteinising hormone pulse characteristics, daily sperm production, plasma testosterone and anti-Müllerian hormone levels were not different in the male offspring of dams administered dihydrotestosterone (DHT) during late gestation compared to controls. Androgen receptor expression was quantified through the hypothalamus and identified as unchanged. Confocal imaging of gonadotropin-releasing hormone (GnRH) neurons revealed that in contrast with prenatally androgenised female mice, PNAM mice exhibited no differences in the density of putative GABAergic innervation compared to controls. These data indicate that a maternal androgen environment capable of inducing reproductive dysfunction in female offspring has no evident impact on the reproductive axis of male littermates in adulthood.

Developmental Programming: Contribution of Epigenetic Enzymes to Antral Follicular Defects in the Sheep Model of PCOS

Prenatal testosterone (T)-treated sheep, similar to women with polycystic ovary syndrome (PCOS), manifest oligo-/anovulation, hyperandrogenism, and polyfollicular ovary. The polyfollicular ovarian morphology, a result of persistence of antral follicles, arises, in part, by transcriptional changes in key mediators of follicular development that, in turn, are driven by epigenetic mechanisms. We hypothesized that prenatal T excess induces, in a cell-specific manner, transcriptional changes in key mediators of follicular development associated with relevant changes in epigenetic machinery. Expression levels of key mediators of follicular development, DNA methyltransferases (DNMTs), and histone de-/methylases and de-/acetylases were determined in laser-capture microdissection-isolated antral follicular granulosa and theca and ovarian stromal cells from 21 months of age control and prenatal T-treated sheep (100 mg IM twice weekly from gestational day 30 to 90; term: 147 days). Changes in histone methylation were determined by immunofluorescence. Prenatal T treatment induced the following: (i) cell-specific changes in gene expression of key mediators of follicular development and steroidogenesis; (ii) granulosa, theca, and stromal cell-specific changes in DNMTs and histone de-/methylases and deacetylases, and (iii) increases in histone 3 trimethylation at lysine 9 in granulosa and histone 3 dimethylation at lysine 4 in theca cells. The pattern of histone methylation was consistent with the expression profile of histone de-/methylases in the respective cells. These findings suggest that changes in expression of key genes involved in the development of the polyfollicular phenotype in prenatal T-treated sheep are mediated, at least in part, by cell-specific changes in epigenetic-modifying enzymes.

Role for androgens in determination of ovarian fate in the common snapping turtle, Chelydra serpentina

Sex steroids are involved in sex determination in almost all vertebrates, including species with temperature-dependent sex determination (TSD). It is well established that aromatase and estrogens are involved in ovary determination in TSD species. In contrast, the role of non-aromatizable androgens in TSD is less clear. In this study, we used dihydrotestosterone (DHT) and an antagonist of the mammalian androgen receptor (flutamide) to examine the impact of androgens on sex determination in the snapping turtle. We incubated eggs at a male-producing temperature and treated embryos with drug delivery vehicle (5 L ethanol), DHT in vehicle, or flutamide in vehicle during the sex-determining period. We then measured expression of markers for ovarian and testicular development and genes involved in steroidogenesis. A subset of embryos and hatchlings were collected for histological analysis of gonad differentiation and sex determination. DHT and flutamide both induced ovarian development: 100% of vehicle-treated hatchlings had testes, while 60% of DHT-treated and 32% flutamide-treated hatchlings had ovaries. DHT and flutamide treatments also had feminizing effects on gene expression patterns and the structure of embryonic gonads. DHT treatment increased expression of FoxL2, androgen receptor, aromatase and several steroidogenic genes. Flutamide produced a similar, but weaker, pattern of gene expression. Genes involved in testis development (Sox9 and Amh) were influenced by flutamide treatment. Our findings support the hypothesis that androgens and the androgen receptor are involved in ovary determination in the common snapping turtle.

Developmental Programming of PCOS Traits: Insights from the Sheep

Polycystic ovary syndrome (PCOS) is a complex disorder that results from a combination of multiple factors, including genetic, epigenetic, and environmental influences. Evidence from clinical and preclinical studies indicates that elevated intrauterine androgen levels increase the susceptibility of the female offspring to develop the PCOS phenotype. Additionally, early postnatal endocrine and metabolic imbalances may act as a "second-hit", which, through activational effects, might unmask or amplify the modifications programmed prenatally, thus culminating in the development of adult disease. Animal models provide unparalleled resources to investigate the effects of prenatal exposure to androgen excess and to elucidate the etiology and progression of disease conditions associated with this occurrence, such as PCOS. In sheep, prenatal treatment with testosterone disrupts the developmental trajectory of the fetus, culminating in adult neuroendocrine, ovarian, and metabolic perturbations that closely resemble those seen in women with PCOS. Our longitudinal studies clearly demonstrate that prenatal exposure to testosterone excess affects both the reproductive and the metabolic systems, leading to a self-perpetuating cycle with defects in one system having an impact on the other. These observations in the sheep suggest that intervention strategies targeting multiple organ systems may be required to prevent the progression of developmentally programmed disorders.

Inferior fertility and higher concentrations of anti-Müllerian hormone in dairy cows with longer anogenital distance

Anogenital distance (AGD), which is an indicator of prenatal androgen exposure, has been reported to have high variability and negative association with fertility in dairy cows. Prenatal exposure to androgens could influence the development of primordial follicles and size of ovarian reserve, which is related to reproduction. However, the relationship between AGD and size of ovarian reserve has not been studied. Therefore, the present study was conducted to determine the association between AGD and circulating anti-Müllerian hormone (AMH), as an indirect marker of ovarian reserve, and to evaluate serum AMH concentration and reproductive performance in dairy cows with short and long AGD. Anogenital distance was measured 28 to 32 d postpartum, and based on the median of AGD, cows were divided into 2 subsets including short (n = 43) and long (n = 43) AGD groups. Afterward, serum AMH was evaluated on the day of estrus in cows that were estrus-synchronized. Furthermore, reproductive data of dairy cows during the previous lactation period were collected from the herd database. Concentrations of serum AMH tended to be positively associated with length of AGD, and there was a tendency for higher serum AMH concentrations in the long (634.89 ± 74.52 pg/mL) than short (451.39 ± 45.92 pg/mL) AGD group (0.05 <P ≤ 0.10). There was a tendency for more days to first service, lower first service conception rate, and higher proportion of repeat breeders in long (99.95 ± 5.34 d, 30.23% and 32.56%, respectively) than short (89.07 ± 4.97 d, 48.84% and 16.28%, respectively) AGD cows (0.05 <P ≤ 0.10). Services per conception did not differ between short (2.30 ± 0.27) and long (2.93 ± 0.29) AGD cows (P > 0.05). Calving to conception interval was prolonged in long (194.30 ± 17.12 d) than short (147.14 ± 13.11 d) AGD cows (P ≤ 0.05). In conclusion, the present study revealed elevated serum AMH concentrations and poor reproductive performance in cows with longer AGD compared with cows with shorter AGD.

Physiological and Pathological Androgen Actions in the Ovary

Androgens, although traditionally thought to be male sex steroids, play important roles in female reproduction, both in healthy and pathological states. This mini-review focuses on recent advances in our knowledge of the role of androgens in the ovary. Androgen receptor (AR) is expressed in oocytes, granulosa cells, and theca cells, and is temporally regulated during follicular development. Mouse knockout studies have shown that AR expression in granulosa cells is critical for normal follicular development and subsequent ovulation. In addition, androgens are involved in regulating dynamic changes in ovarian steroidogenesis that are critical for normal cycling. Androgen effects on follicle development have been incorporated into clinical practice in women with diminished ovarian reserve, albeit with limited success in available literature. At the other extreme, androgen excess leads to disordered follicle development and anovulatory infertility known as polycystic ovary syndrome (PCOS), with studies suggesting that theca cell AR may mediate many of these negative effects. Finally, both prenatal and postnatal animal models of androgen excess have been developed and are being used to study the pathophysiology of PCOS both within the ovary and with regard to overall metabolic health. Taken together, current scientific consensus is that a careful balance of androgen activity in the ovary is necessary for reproductive health in women.

A Hyperandrogenic Environment Causes Intrinsic Defects That Are Detrimental to Follicular Dynamics in a PCOS Mouse Model

Polycystic ovary syndrome (PCOS) is a common cause of female infertility. Hyperandrogenism is both a major symptom and key diagnostic trait of PCOS; however, the direct impact of this androgen excess on ovarian dynamics is unclear. By combining a DHT-induced PCOS mouse model with an ex vivo follicle culture system, we investigated the impact of hyperandrogenism on ovarian function. Ovaries from PCOS mice exhibited the characteristic polycystic ovary morphology with numerous large cystic follicles and no corpora lutea present. Isolation and individual culture of preantral and antral follicles from PCOS mice resulted in slower growth rates during 5 days compared with the follicles isolated from control mice (P < 0.01). In contrast, preovulatory follicles from PCOS mice exhibited a significant increase in growth rate compared with controls (P < 0.01). Preantral follicles from PCOS ovaries maintained comparable follicular health as control follicles, but antral and preovulatory PCOS follicles exhibited reduced follicle health (P < 0.01) and survival rates (P < 0.01). Compared with controls, PCOS females also exhibited a poorer response to hyperstimulation (P < 0.01), impaired oocyte function evident by increased levels of reactive oxygen species (P < 0.01), and a reduction in on-time embryo development (P < 0.01). These results demonstrate that prolonged exposure to androgen excess leads to aberrant follicle development, which persists even after removal from the hyperandrogenic environment, causing perturbed follicular developmental trajectories. These findings indicate that an in vivo hyperandrogenic environment in patients with PCOS may intrinsically induce detrimental effects on follicles and oocytes.

Maternal β-hydroxy-β-methylbutyrate (HMB) supplementation during pregnancy affects early folliculogenesis in the ovary of newborn piglets

Beta-hydroxy-beta-methylbutyrate (HMB) is a leucine metabolite with protein anabolic effects. This study was designed to determine whether prenatal HMB treatment has an effect on oogenesis and folliculogenesis in the ovary of newborn piglets. HMB decreased the number of egg nests and primordial follicles and increased the pool of developing follicles compared to the control group. Although the percentage of TUNEL-positive oocytes within the egg nests was higher in HMB-treated group no increase in the Bax/Bcl-2 ratio and active caspase-3 expression was observed. Moreover, the granulosa cell proliferation index and StAR protein expression were higher in HMB-treated group. In contrast to the control group, the expression of E-cadherins was reduced after the HMB treatment. In addition, a significant increase in the serum level of gonadotropins and steroid hormones was detected in HMB-treated piglets. In conclusion, prenatal HMB treatment dysregulates hormonal homeostasis which impairs early folliculogenesis in piglets.

Chronic hyperandrogenemia and western-style diet beginning at puberty reduces fertility and increases metabolic dysfunction during pregnancy in young adult, female macaques

STUDY QUESTION

What are the impacts of elevated testosterone (T) and an obesogenic western-style diet (WSD), either independently or together, on fertility and metabolic adaptations of pregnancy in primates?

SUMMARY ANSWER

Testosterone increases the time to achieve pregnancy, while a WSD reduces overall fertility, and the combination of testosterone and WSD additionally impairs glucose tolerance and causes pregnancy loss.

WHAT IS KNOWN ALREADY

Both hyperandrogenemia and obesity are hallmarks of polycystic ovary syndrome, which is a leading cause of infertility among women worldwide. Female macaques receiving T and WSD beginning at puberty show increased metabolic, ovarian and uterine dysfunction in the non-pregnant state by 3 years of treatment.

STUDY DESIGN, SIZE, DURATION

The same cohort of female rhesus macaques continued treatments from the time of puberty (2.5 years) to 4 years, including this fertility trial. There were four groups (n = 9-10/group): controls (C), T-treated (T; average total serum level 1.35 ng/ml), WSD-treated, and combined T and WSD-treated (T + WSD) females.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Females, which were typically having menstrual cycles, were paired for 4 days with a proven male breeder following the late follicular rise in circulating estradiol (≥100 pg/ml). The presence of sperm in the reproductive tract was used to confirm mating. Animals went through up to three successive rounds of mating until they became pregnant, as confirmed by a rise in circulating mCG during the late luteal phase and ultrasound evidence of a gestational sac at Day 30 post-mating (GD30). Placental vascular parameters were also measured at GD30. Metabolic measurements consisted of fasting levels of blood glucose and insulin at approximately GD30, 60, 90 and 115, as well as an intravenous (iv) glucose tolerance test (GTT) at GD115.

MAIN RESULTS AND THE ROLE OF CHANCE

While all animals in the C and T groups eventually became pregnant, T-treated females on average had a greater interval to achieve pregnancy (P < 0.05). However, only ~70% of animals in the WSD and T + WSD groups became pregnant (P < 0.004). One pregnancy in T + WSD group resulted in an anembryonic pregnancy which miscarried around GD60, while another T + WSD female conceived with a rare identical twin pregnancy which required cessation due to impending fetal loss at GD106. Thus, the number of viable fetuses was less in the T + WSD group, compared to C, T or WSD. Placental blood volume at GD30 was reduced in all treatments compared to the C group (P < 0.05). Maternal P4 levels were elevated in the WSD (P < 0.03) group and E2 levels were elevated in T + WSD animals (P < 0.05). An increase in serum A4 levels throughout gestation was observed in all groups (P < 0.03) except WSD (P = 0.3). All groups displayed increased insulin resistance with pregnancy, as measured from the ivGTT during pregnancy. However, only the T + WSD group had a significant increase in fasting glucose levels and glucose clearance during the GTT indicating a worsened glucose tolerance. WSD treatment decreased female fetuses third trimester weights, but there was an interaction between WSD and T to increase female fetal weight when normalized to maternal weight.

LARGE SCALE DATA

N/A.

LIMITATIONS REASONS FOR CAUTION

The small number of pregnancies in the WSD and T + WSD groups hampers the ability to make definitive conclusions on effects during gestation. Also, the high fertility rate in the controls indicates the cohort was at their breeding prime age, which may impair the ability to observe subtle fertility defects. The low number of fetuses used for male and female analysis requires additional studies.

WIDER IMPLICATIONS OF THE FINDINGS

The current findings strongly suggest that both hyperandrogenemia and obesity have detrimental effects on fertility and gestation in primates, which may be directly relevant to women with polycystic ovary syndrome.

STUDY FUNDING/COMPETING INTEREST(S)

All ONPRC Cores and Units were supported by NIH Grant P51 OD011092 awarded to ONPRC. Research reported in this publication was supported by the Eunice Kennedy Shriver National Institute of Child Health & Human Development (NICHD) of the National Institutes of Health (NIH) under Award Number P50HD071836 (to R.L.S.). The authors have no competing conflict of interests to disclose.

Maternal exposure to bisphenol A and anogenital distance throughout infancy: A longitudinal study from Shanghai, China

BACKGROUND

Bisphenol A (BPA) is one of the most common endocrine-disrupting compounds (EDCs) with a ubiquitous presence. Both animal and human studies have reported the association between maternal exposure to BPA and anogenital distance (AGD) in offspring. However, the results are conflicting and the longitudinal effect is unknown. We aimed to examine the effect of maternal exposure to BPA on AGD in offspring in a longitudinal birth cohort from birth to 1 year of age.

METHODS

BPA was assayed using urine samples collected at 12-16 gestational weeks from 982 pregnant participants who later delivered infants. Infants' AGDs (AGDap [anus-penis] and AGDas [anus-scrotum] for boys, AGDac [anus-clitoris] and AGDaf [anus-fourchette] for girls) were measured at birth, and at 6 and 12 months of age. Multiple linear regression analysis was conducted to examine the associations between maternal exposure to BPA and offspring's AGDs. Then generalized estimating equation (GEE) model was applied to make use of the repeated measurements of AGDs and examine the overall effect of maternal exposure to BPA.

RESULTS

Compared to boys with undetected maternal BPA, those with detected BPA were more likely to have shorter AGDap and AGDas at 6 and 12 months. However, the differences were statistically significant for AGDap and AGDas only at 12 months (2.87 and 4.12 mm shorter, respectively). In GEE models, similar patterns were observed. Boys in the higher quartiles were more likely to have shorter AGDap and AGDas than those in the first quartile. However, statistically significant differences were only observed in boys in the third quartile. For girls, these associations were not observed regardless of the timing of measurements (at birth, 6 months and 12 months).

CONCLUSIONS

Maternal exposure to BPA was associated with shortened AGDap and AGDas in boys at age 12 months but not in girls, which suggests a gender specific effect of BPA exposure on offspring's development.

Cardiac myocyte proliferation and maturation near term is inhibited by early gestation maternal testosterone exposure

Polycystic ovary syndrome is a complex and common disorder in women, and those affected experience an increased burden of cardiovascular disease. It is an intergenerational syndrome, as affected women with high androgen levels during pregnancy "program" fetal development, leading to a similar phenotype in their female offspring. The effect of excess maternal testosterone exposure on fetal cardiomyocyte growth and maturation is unknown. Pregnant ewes received biweekly injections of vehicle (control) or 100 mg testosterone propionate between 30 and 59 days of gestation (early T) or between 60 and 90 days of gestation (late T). Fetuses were delivered at ~135 days of gestation, and their hearts were enzymatically dissociated to measure cardiomyocyte growth (dimensional measurements), maturation (proportion binucleate), and proliferation (nuclear Ki-67 protein). Early T depressed serum insulin-like growth factor 1 and caused intrauterine growth restriction (IUGR; P < 0.0005). Hearts were smaller with early T ( P < 0.001) due to reduced cardiac myocyte maturation ( P < 0.0005) and proliferation ( P = 0.017). Maturation was also lower in male than female fetuses ( P = 0.004) independent of treatment. Late T did not affect cardiac growth. Early excess maternal testosterone exposure depresses circulating insulin-like growth factor 1 near term and causes IUGR in both female and male offspring. These fetuses have small, immature hearts with reduced proliferation, which may reduce cardiac myocyte endowment and predispose to adverse cardiac growth in postnatal life. While excess maternal testosterone exposure leads to polycystic ovary syndrome and cardiovascular disease in female offspring, it may also predispose to complications of IUGR and cardiovascular disease in male offspring. NEW & NOTEWORTHY Using measurements of cardiac myocyte growth and maturation in an ovine model of polycystic ovary syndrome, this study demonstrates that early gestation excess maternal testosterone exposure reduces near-term cardiomyocyte proliferation and maturation in intrauterine growth-restricted female and male fetuses. The effect of testosterone is restricted to exposure during a specific period early in pregnancy, and the effects appear mediated through reduced insulin-like growth factor 1 signaling. Furthermore, male fetuses, regardless of treatment, had fewer mature cardiomyocytes than female fetuses.

Ovarian and Extra-Ovarian Mediators in the Development of Polycystic Ovary Syndrome

Polycystic ovary syndrome (PCOS) is a heterogeneous endocrine disorder affecting women of reproductive age. The origin of PCOS is still not clear and appears to be a function of gene x environment interactions. This review addresses the current knowledge of the genetic and developmental contributions to the etiology of PCOS, the ovarian and extra-ovarian mediators of PCOS and the gaps and key challenges that need to be addressed in the diagnosis, treatment and prevention of PCOS.

Androgens in maternal vascular and placental function: implications for preeclampsia pathogenesis

Adequate maternal vascular adaptations and blood supply to the uterus and placenta are crucial for optimal oxygen and nutrient transport to growing fetuses of eutherian mammals, including humans. Multiple factors contribute to hemodynamics and structuring of placental vasculature essential for term pregnancy with minimal complications. In women, failure to achieve or sustain favorable pregnancy progression is, not surprisingly, associated with high incidence of antenatal complications, including preeclampsia, a hypertensive disorder of pregnancy. While the pathogenesis of preeclampsia in women remains unknown, a role for androgens is emerging. The relationship between androgens and maternal cardiovascular and placental function deserves particular consideration because testosterone levels in the circulation of preeclamptic women are elevated approximately two- to three-fold and are positively correlated with vascular dysfunction. Preeclampsia is also associated with elevated placental androgen receptor (AR) gene expression. Studies in animal models mimicking the pattern and level of increase of adult female testosterone levels to those found in preeclamptic pregnancies, replicate key features of preeclampsia, including gestational hypertension, endothelial dysfunction, exaggerated vasoconstriction to angiotensin II, reduced spiral artery remodeling, placental hypoxia, decreased nutrient transport and fetal growth restriction. Taken together, these data strongly implicate AR-mediated testosterone action as an important pathway contributing to clinical manifestation of preeclampsia. This review critically addresses this hypothesis, taking into consideration both clinical and preclinical data.

Prenatal Steroids and Metabolic Dysfunction: Lessons from Sheep

Prenatal exposure to excess steroids or steroid mimics can disrupt the normal developmental trajectory of organ systems, culminating in adult disease. The metabolic system is particularly susceptible to the deleterious effects of prenatal steroid excess. Studies in sheep demonstrate that prenatal exposure to excess native steroids or endocrine-disrupting chemicals with steroidogenic activity, such as bisphenol A, results in postnatal development of numerous cardiometabolic perturbations, including insulin resistance, increased adiposity, altered adipocyte size and distribution, and hypertension. The similarities in the phenotypic outcomes programmed by these different prenatal insults suggest that common mechanisms may be involved, and these may include hormonal imbalances (e.g., hyperandrogenism and hyperinsulinemia), oxidative stress, inflammation, lipotoxicity, and epigenetic alterations. Animal models, including the sheep, provide mechanistic insight into the metabolic repercussions associated with prenatal steroid exposure and represent valuable research tools in understanding human health and disease. Focusing on the sheep model, this review summarizes the cardiometabolic perturbations programmed by prenatal exposure to different native steroids and steroid mimics and discusses the potential mechanisms underlying the development of adverse outcomes.

Nulliparous and primiparous cows produce less fertile female offspring with lesser concentration of anti-Müllerian hormone (AMH) as compared with multiparous cows

Nutritional partitioning to fetal development differ among nulliparous, primiparous and multiparous cows, leading to birth of smaller calves to nulliparous and primiparous than multiparous dams. The prenatal nutritional state could influence ovarian reserve and fertility in the adult offspring. The effect of maternal parity on ovarian reserve and reproduction of female offspring, however, has not been investigated in cattle. Accordingly, a retrospective research was conducted to study reproductive variables in nulliparous- (n = 310), primiparous- (n = 236) and multiparous-born (n = 323) female offspring during the first four lactation periods in dairy cows. Additionally, anti-Müllerian hormone (AMH), as a reliable marker of ovarian reserve, was measured in a subset of nulliparous- (n = 51), primiparous- (n = 51) and multiparous-born (n = 49) female offspring. Birth weight in multiparous-born calves was greater than that in nulliparous- and primiparous-born calves (P <  0.01). Days to first service was shorter in multiparous-born female offspring as compared with nulliparous- and primiparous-born female offspring (P <  0.05). First service conception rate, proportion of repeated breeders, service per conception and calving to conception interval were greater in multiparous-born than nulliparous-born cows (P <  0.05). Cumulative culling rate was greater in primiparous-born cows than nulliparous- and multiparous-born cows (P <  0.05). The AMH concentration was greater in multiparous-born than nulliparous- and primiparous-born cows (P <  0.05). In conclusion, the present study revealed that in comparison with multiparous cows, nulliparous and primiparous cows, particularly nulliparous cows, produce female offspring with lesser reproductive performance and smaller size of ovarian reserves.