Endocrine Abstracts

Smoking has many effects on human health and reproduction. Women are generally recommended to quit smoking before conception. Cessation improves fertility and helps avoid many health risks for the mother and the child and plays an important role in the future development and health of the offspring. We have decided to perform a study following changes in the production of steroid hormones in pregnant smokers and ex-smokers compared to non-smokers. In physiological pregnancies, there are differences in the levels of steroid hormones in a pregnant woman depending on the sex of the fetus, and there are differences in the steroids of newborns depending on their sex and the type of delivery. We have focused on changes in steroidogenesis in the blood of mothers in their 37^th week of pregnancy and in mixed cord blood of their newborns. The study included 47 healthy women, of which 14 were active smokers, 11 ex-smokers (smoking cessation lasts more than a year), and 22 non-smokers. All women had physiological course of gravidity, gave birth spontaneously, and carried female fetus. Selected steroid hormones (cortisol, cortisone, dehydroepiandrosterone (DHEA), 7α-hydroxy-dehydroepiandrosterone, (7α-OH-DHEA), 7β-hydroxy-dehydroepiandrosterone, (7β-OH-DHEA), 7-oxo-dehydroepiandrosterone (7-oxo-DHEA), pregnenolone, 17α-hydroxy-pregnenolone (17-OH-pregnenolone), testosterone, androstenedione, progesterone, 17-OHprogesterone, corticosterone, estrone, estradiol, and estriol) were measured using methods LC-MS/MS. Local ethical committee approved the study. We found higher levels of androstenedione and lower levels of 17-OH-pregnenolone at the 37^th week of pregnancy in smokers and ex-smokers compared to non-smokers. The levels of 7β-OH-DHEA, 7-oxo-DHEA were lower in smokers compared to ex-smokers and non-smokers. Other measured steroids did not differ for ex-smokers or smokers. We have measured lower levels of 7α -OH-DHEA in female newborns delivered by non-smokers compared to other groups, while other measured hormones showed no significant differences. Even a history of smoking can induce changes in the production of steroids during pregnancy. Our study shows that hormonal dysbalances found in pregnant ex-smokers could be similar to pregnant smokers for some steroids, while levels of other steroids will normalize with abstinence. This finding correlates with our data from previous studies and studies of other authors about long lasting influence of smoking on steroid metabolome. However, the results of our study are limited by the smaller number of participants.