RESULTS
Three thousand and twenty pregnant women have been included in our study. The mean age of the study participants was 29 (±5) years. Initial body mass index of participants was 26 (±7) kg/m². Among those 3020 women, 623 (21,6%) were living and/or working in H2S exposed areas and 194 (6,4%) met the primary endpoint, i.e., preeclampsia, during the follow-up period. In the exposed population, median H2S concentration, averaged across pregnancy length, was 300 ppb (IQR H-spread 197). Main characteristics of H2S exposed and non-exposed pregnant women are presented Table 1. There were no differences (p=0.20) in preeclampsia incidence rate between H2S exposed and non-exposed pregnant women during the follow-up period (7.5% versus 6.1%, respectively). In sharp contrast, time to preeclampsia between the 20th and 37th week of amenorrhea was shorter (p=0.02) in H2S exposed compared with non-exposed pregnant women (median=30.9 months - IQR 8.6 versus 32.9 months - IQR 6.0, respectively) (Figure1).