Fig. 4

The effects of maternal smoking on intra-adrenal steroid levels during the second trimester. Measurements from individual fetuses are shown. Steroids are expressed as ng per total combined adrenal weight (n = 60). Maternal smoking was associated with altered intra-adrenal levels of three of the 19 steroids measured during the second trimester: progesterone (P = 0.02), 17α-hydroxyprogesterone (P = 0.02) and 16α-hydroxyprogesterone (P = 0.04) with P values corresponding to the interaction between smoke exposure and gestational age. Black lines show generalized linear regressions, and grey fill shows the confidence interval (0.95) around the regression