RESUMEN
OBJECTIVE: Hypertension and smoking during pregnancy have been linked to various adverse maternal and fetal outcomes. The objective of this work is to study how the smoking influences the development of hypertension, its effects on the pregnant woman, and on the newborn. MATERIALS AND METHODS: An observational study in two phases was carried out: the descriptive first phase allows characterization of the sample and the analytical second phase is a case-control nested in a retrospective cohort corresponding to pregnancy. RESULTS: A total of 712 women were included in the study. Of the 672 (94.4%) non-hypertensive women, 533 (79.3%) were non-smoking and 139 (20.7%) smoking. For the 40 (5.6%) hypertensive women, 30 (75.0%) were non-smoking and 10 (25.0%) smoking. The prevalence of hypertension was of 5.6%. Women who quit smoking before pregnancy saw a reduced risk of hypertension. For women who smoke during pregnancy, those of younger ages, with a normal body mass index, who are primiparous, employed and with a low-medium level of education have higher risk of hypertension. The risk of hypertension according to the level of physical activity during leisure time follows a "U" shape, with those who perform light physical activity at the lowest risk of hypertension. Hypertensive women have a higher risk of small for gestational age newborns. Smoking does not pose an additional risk for adverse outcomes once hypertension is diagnosed. CONCLUSIONS: Future studies should aim to determine the role of smoking habit in the appearance of hypertension in pregnancy in order to establish adequate intervention guidelines that may aid in reducing the prevalence of hypertension.