Androgens in the maternal and fetal circulation: association with insulin resistance

To examine maternal insulin resistance in relationship with maternal and fetal androgen levels as well as with term placenta mRNA and protein abundance of steroidogenic enzymes implicated in androgen dynamics.The study included 20 women with gestational diabetes mellitus and 27 controls tested using a 120 min., 75 g oral glucose tolerance test. Maternal and fetal plasma concentrations of total testosterone, dihydrotestosterone (DHT) and dehydroepiandrosterone (DHEA) were measured by high-performance gas chromatography and chemical ionization mass spectrometry at 26.1 ± 3.7 weeks of pregnancy.Glycemic response to oral glucose over 120 min. as well as Matsuda insulin sensitivity and HOMA insulin resistance (HOMA-IR) indices were significantly associated with maternal testosterone levels (r = 0.31, r = -0.37 and r = 0.35 respectively, p ≤ 0.05 for all). Among male offspring, a positive association between maternal and fetal testosterone levels was observed (r = 0.43, p ≤ 0.05). Testosterone levels were higher in the cord blood of newborns from insulin-resistant mothers compared to newborns from insulin-sensitive mothers (0.48 ± 0.36 nmol/L vs. 0.29 ± 0.18 nmol/L p ≤ 0.05). No difference was observed in mRNA abundance or protein expression of placental steroidogenic enzymes according to the degree of maternal insulin resistance.Our results demonstrate a possible association between fetal and maternal androgen concentrations in relationship with insulin resistance.