Correlation of maternal concentrations of plasma testosterone with fetal sex in horses

ABSTRACT: The objectives of this study were to evaluate the correlation of fetal sex and plasma testosterone concentrations between the 5th and 8th months of pregnancy in mares and to verify the applicability of this test to predict fetal sex. Blood samples were collected from 21 mares at 30-day intervals of between 150 and 240 days of pregnancy. Plasma testosterone was determined by radioimmunoassay and the sex of the foals confirmed at birth. The levels of maternal testosterone were higher in mares carrying female fetuses at months 5 and 8 (P < 0.05). Limit values were determined by analyzing the receiver operating characteristic (ROC) estimates: 35.5 pg/mL and 40 pg/mL for the 5th and 8th month, respectively. For the mares with plasma testosterone values equal to or above the threshold, gestation of female foals was predicted, and for those with plasma testosterone below the threshold values pregnancy of male foals was predicted. In the 5th month, the predictive values for male and female fetuses were 70% and 88.9%, respectively; the detection rates were 87.5% and 72.7%, and the total accuracy of the examination was 78.9%. In the 8th month, the predictive values for male and female fetuses were 80% and 90%, respectively; the detection rates were 88.9% and 81.8%, and the total accuracy of the examination was 85%. It was concluded that there was a correlation between fetal sex and plasma testosterone concentrations in pregnant mares. Prediction of fetal sex based on plasma concentrations of maternal testosterone can be performed in months 5 and 8 with 78.9% and 85% accuracy, respectively.

Co-evolved maternal effects selectively eliminate offspring depending on resource availability

Many plants and animals adaptively downsize the number of already-produced propagules if resources become insufficient to raise all of them. In birds, mothers often induce hatching asynchrony by incubating first eggs before last eggs are laid, creating an age/size hierarchy within broods which selectively eliminates the smallest chicks in poor food conditions. However, mothers also deposit more testosterone into late-laid eggs, which boosts competitive abilities of younger chicks, counteracts the competitive hierarchy, and ostensibly creates a paradox. Since testosterone also carries costs, we hypothesized that benefits of maternally deposited testosterone outweigh its costs in good food conditions, but that testosterone has a net detrimental effect in poor food conditions. We found experimental evidence that elevated maternal testosterone in the egg caused higher chick mortality in poor food conditions but better chick growth in good food conditions. These context-dependent effects resolve the paradox, suggesting co-evolution of two maternal effects, and explain inconsistent results of egg hormone manipulations in the literature.

Testosterone Decreases Placental Mitochondrial Content and Cellular Bioenergetics

Placental mitochondrial dysfunction plays a central role in the pathogenesis of preeclampsia. Since preeclampsia is a hyperandrogenic state, we hypothesized that elevated maternal testosterone levels induce damage to placental mitochondria and decrease bioenergetic profiles. To test this hypothesis, pregnant Sprague–Dawley rats were injected with vehicle or testosterone propionate (0.5 mg/kg/day) from gestation day (GD) 15 to 19. On GD20, the placentas were isolated to assess mitochondrial structure, copy number, ATP/ADP ratio, and biogenesis (Pgc-1α and Nrf1). In addition, in vitro cultures of human trophoblasts (HTR-8/SVneo) were treated with dihydrotestosterone (0.3, 1.0, and 3.0 nM), and bioenergetic profiles using seahorse analyzer were assessed. Testosterone exposure in pregnant rats led to a 2-fold increase in plasma testosterone levels with an associated decrease in placental and fetal weights compared with controls. Elevated maternal testosterone levels induced structural damage to the placental mitochondria and decreased mitochondrial copy number. The ATP/ADP ratio was reduced with a parallel decrease in the mRNA and protein expression of Pgc-1α and Nrf1 in the placenta of testosterone-treated rats compared with controls. In cultured trophoblasts, dihydrotestosterone decreased the mitochondrial copy number and reduced PGC-1α, NRF1 mRNA, and protein levels without altering the expression of mitochondrial fission/fusion genes. Dihydrotestosterone exposure induced significant mitochondrial energy deficits with a dose-dependent decrease in basal respiration, ATP-linked respiration, maximal respiration, and spare respiratory capacity. In summary, our study suggests that the placental mitochondrial dysfunction induced by elevated maternal testosterone might be a potential mechanism linking preeclampsia to feto-placental growth restriction.

Maternal Testosterone Excess Contributes to Reproductive System Dysfunction of Female Offspring Mice

Hyperandrogenism is considered 1 of the most important characteristics of polycystic ovary syndrome, which affects more than 10% of females of reproductive age and is a common cause of infertility. In addition to the effects on patients themselves, maternal androgen excess has also been reported to impair the growth and development of offspring. In our current study, we found that maternal testosterone (T) treatment during different gestational stages increased the percentage of atretic follicle and decreased corpus luteum formation in female offspring. In addition, decreased serum estradiol and increased T levels were also observed in female offspring of T-treated mice during late gestational stage. Further studies revealed that Forkhead box protein L2 (FOXL2) and Cytochrome P450 family 19 subfamily a member 1 (CYP19A1) expression in granulosa cells of these female offspring mice were decreased. By using mouse primary granulosa cells and the KGN cell line, we demonstrated that decreasing FOXL2 and CYP19A1 levels in ovarian granulosa cells partially may contribute to disturbed sex hormone synthesis in female offspring of T-treated mice during the late gestational stage. Findings from our current study highlight a critical role of excess maternal T exposure, especially during the late gestational stage, which could further lead to aberrant ovary development and sex hormone synthesis in female offspring.

Anogenital distance in children born of mothers with polycystic ovary syndrome: the Odense Child Cohort

STUDY QUESTIONAre higher testosterone levels during pregnancy in women with polycystic ovary syndrome (PCOS) associated with longer offspring anogenital distance (AGD)?SUMMARY ANSWERAGD was similar in 3-month-old children born of mothers with PCOS compared to controls.WHAT IS KNOWN ALREADYAGD is considered a marker of prenatal androgenization.STUDY DESIGN, SIZE, DURATIONMaternal testosterone levels were measured by mass spectrometry at Gestational Week 28 in 1127 women. Maternal diagnosis of PCOS before pregnancy was defined according to Rotterdam criteria. Offspring measures included AGD from anus to posterior fourchette (AGDaf) and clitoris (AGDac) in girls and to scrotum (AGDas) and penis (AGDap) and penile width in boys and body composition (weight and BMI SD scores) at age 3 months.PARTICIPANTS/MATERIALS, SETTING, METHODSThe study was part of the prospective study, Odense Child Cohort (OCC), and included mothers with PCOS (n = 139) and controls (n = 1422). The control population included women with regular menstrual cycles (<35 days) before conception and no signs of androgen excess (hirsutism and/or acne).MAIN RESULTS AND THE ROLE OF CHANCEAGD measures were comparable in offspring of women with PCOS compared to controls (all P > 0.2) despite significantly higher maternal levels of total testosterone (mean: 2.4 versus 2.0 nmol/l) and free testosterone (mean: 0.005 versus 0.004 nmol/l) in women with PCOS versus controls (both P < 0.001). In women with PCOS, maternal testosterone was an independent positive predictor of offspring AGDas and AGDap in boys. Maternal testosterone levels did not predict AGD in girls born of mothers with PCOS or in boys or girls born of women in the control group.LIMITATIONS, REASONS FOR CAUTIONThe diagnosis of PCOS was based on retrospective information and questionnaires during pregnancy. Women participating in OCC were more ethnically homogenous, leaner, more educated and less likely to smoke compared to the background population. Our study findings, therefore, need to be reproduced in prospective study cohorts with PCOS, in more obese study populations and in women of other ethnicities.WIDER IMPLICATIONS OF THE FINDINGSOur finding of the same AGD in girls born of mothers with PCOS compared to controls expands previous results of studies reporting longer AGD in adult women with PCOS. Our results suggest that longer AGD in adult women with PCOS could be the result of increased testosterone levels in puberty, perhaps in combination with weight gain.STUDY FUNDING/COMPETING INTEREST(S)Financial grants for the study were provided by the Danish Foundation for Scientific Innovation and Technology (09-067180), Ronald McDonald Children Foundation, Odense University Hospital, the Region of Southern Denmark, the Municipality of Odense, the Mental Health Service of the Region of Southern Denmark, The Danish Council for Strategic Research, Program Commission on Health, Food and Welfare (2101-08-0058), Odense Patient data Explorative Network, Novo Nordisk Foundation (grant no. NNF15OC00017734), the Danish Council for Independent Research and the Foundation for research collaboration between Rigshospitalet and Odense University Hospital and the Health Foundation (Helsefonden). There is no conflict of interest of any author that could be perceived as prejudicing the impartiality of the research reported.

Maternal Testosterone Levels During Pregnancy Are Not associated with Birth Weights of Offspring: A Prospective Cohort Study

Background Testosterone is an important sex hormone which participates in many physiological processes. However, there is conflicting evidence on effect of testosterone on fetal development. We aim to investigate the associations between maternal testosterone levels and pregnancy outcomes.Design and Methods We conducted a prospective cohort in a university-affiliated hospital. A total of 1,087 singleton pregnant women were included in the study. They were followed-up until delivery. The primary outcome was birth weight. The second outcomes were the prevalence of preterm birth, low birth weight, small for gestational age, preeclampsia, gestational diabetes mellitus, intrahepatic cholestasis of pregnancy, premature rupture of membranes, and low APGAR score (<7).Results We did not observe any significant association between maternal testosterone level and birth weight after adjustment. Prevalence of medical complications was also not associated with maternal testosterone levels.Conclusions Maternal testosterone levels during pregnancy is not associated with birth weights as well as the prevalence of medical complications.

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.