Testosterone and estradiol in maternal plasma and their relation to fetal sex

Digit ratio (2D:4D) and maternal testosterone-to-estradiol ratio measured in early pregnancy

The ratio of index to ring finger (2D:4D) has been hypothesised to indicate prenatal androgen exposure, yet evidence for its validity is lacking. We report the first pre-registered study to investigate mothers' early pregnancy sex hormone concentrations in relation to their children's digit ratios measured at 18-22-month follow-up. Although the testosterone (T) to estradiol (E) ratio correlated negatively with right hand digit ratio (R2D:4D) and directional asymmetry (right-minus-left) in digit ratio (D_[R-L]), neither effect remained statistically significant once demographic and obstetric covariates were controlled for. Nevertheless, the multivariate level of analysis did reveal that T correlated positively with left hand digit ratio (L2D:4D) and negatively with D_[R-L]. However, the first of these effects is in the opposite direction to that predicted by theory. Taken together, the results of our study suggest research with larger samples is required to determine whether digit ratios are valid proxies for maternal sex hormone exposure.

Gestational Hormone Concentrations Are Associated With Timing of Delivery in a Fetal Sex-Dependent Manner

BACKGROUND

Early delivery remains a significant public health problem that has long-lasting impacts on mother and child. Understanding biological mechanisms underlying timing of labor, including endocrine disruption, can inform prevention efforts.

METHODS

Gestational hormones were measured among 976 women in PROTECT, a longitudinal birth cohort in Puerto Rico. We evaluated associations between hormone concentrations at 18 and 26 weeks gestation and gestational age at birth, while assessing effect modification by fetal sex. Exploratory analyses assessed binary outcomes of overall preterm birth (PTB, <37 weeks gestation) and the spontaneous PTB subtype, defined as preterm premature rupture of membranes, spontaneous preterm labor, or both. Multivariable logistic and linear regressions were fit using visit-specific hormone concentrations, and fetal sex-specific effects were estimated using interaction terms. Main outcome models were adjusted for maternal age, education, marital status, alcohol consumption, environmental tobacco smoke exposure, and pre-pregnancy body mass index (BMI). Exploratory models adjusted for maternal age and education.

RESULTS

We observed reduced gestational age at birth with higher circulating CRH (β: -2.73 days, 95% CI: -4.97, -0.42), progesterone (β: -4.90 days, 95% CI: -7.07, -2.73), and fT4 concentrations (β: -2.73 days, 95% CI: -4.76, -0.70) at 18 weeks specifically among male fetuses. Greater odds of overall and spontaneous PTB were observed among males with higher CRH, estriol, progesterone, total triiodothyronine (T3), and free thyroxine (fT4) concentrations. Greater odds of PTB among females was observed with higher testosterone concentrations.

CONCLUSIONS

Various associations between hormones and timing of delivery were modified by fetal sex and timing of hormone measurement. Future studies are needed to understand differential mechanisms involved with timing of labor between fetal sexes.

Androgens and hyperemesis gravidarum: a case-control study

OBJECTIVE

The pathogenesis of hyperemesis gravidarum (HG) is probably multifactorial, involving several hormones. Androgen concentrations are reported to correlate positively with emesis gravidarum. Hypothesizing a continuum between emesis gravidarum and HG, we investigated androgen concentrations in women with HG.

STUDY DESIGN

In a case-control study, 32 women hospitalized for HG were compared with 29 control women scheduled for elective surgical abortion. Control women were matched for age, gestational length, body mass index (BMI) and parity. Patient characteristics and concentrations of dehydroepiandrosterone sulphate (DHEAS), androstenedione, testosterone, sex hormone binding globulin (SHBG), free testosterone index (FTI), androstanediol glucuronide (ADG), progesterone, TSH, free T3 and T4, beta-hCG, ferritin, insulin, estradiol and estriol were compared using Mann-Whitney tests and multivariate linear regression analyses.

RESULTS

Women with HG had higher concentrations of ADG (8.49±4.19 vs. 6.19±1.77pmol/L; p=0.015), estradiol (2.39±1.36 vs. 1.60±9.30nmol/L; p=0.009) and ferritin (186±138 vs. 117±94pmol/L; p=0.040) compared with control women. Androstenedione (5.34±2.82 vs. 6.86±2.67; p=0.004) and insulin (63.7±35.0 vs. 75.3±25.8; p=0.050) concentrations were lower in women with HG. DHEAS, testosterone, FTI, SHBG, estriol, progesterone, beta-hCG, TSH, free T3 and free T4 concentrations did not differ between the groups. In multivariate regression analyses HG was associated with high concentrations of ADG (p=0.026) and low concentrations of androstenedione (p=0.018).

CONCLUSION

Steroid hormone homeostasis may be altered in women with HG. HG may be associated with high ADG and low androstenedione concentrations.

Fetal sex-related dysregulation in testosterone production and their receptor expression in the human placenta with preeclampsia

OBJECTIVE

To determine the effects of fetal sex on aromatase and androgen receptor (AR) expression in the placenta of normal and preeclamptic pregnancies.

STUDY DESIGN

Placentae from preeclamptic (five female and six male fetuses) and healthy pregnancies (seven female and seven male fetuses) were examined by immunofluorescence, western blotting and quantitative reverse transcriptase PCR.

RESULT

Placental AR levels were significantly higher (P<0.05) in placentae of both male and female fetuses compared with their respective sexes in normal pregnancies. The placental aromatase levels varied depending on fetal sex. If the fetus was female, aromatase levels were substantially higher (P<0.05) in preeclamptic than in normal placentae. If the fetus was male, the aromatase levels were significantly lower (P<0.05) in preeclamptic than in normal placentae. Placental aromatase levels were significantly higher (P<0.05) in male- than in female-bearing normal placentae.

CONCLUSION

Dysregulation in androgen production and signaling in preeclamptic placentae may contribute to placental abnormalities, increasing the frequency of maternal-fetal complications associated with preeclampsia.