Smoking Status in Pregnancy: A Retrospective Analysis in Northern Greece.

Smoking has adverse effects on both maternal and fetal health and its incidence varies among different countries. The aim of this study was to identify the prevalence of smoking during pregnancy and to identify factors associated with smoking. This was a retrospective study conducted at the Third Department of Obstetrics and Gynecology, School of Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki, Greece, during an 11-year period (2013-2023). All women receiving antenatal care in our unit were eligible to participate when they attended the prenatal unit for the first trimester nuchal translucency scan (11-13 weeks). Of the 12,074 pregnant women included in the study, 5005 (41.5%) reported themselves as smokers before pregnancy; the smoking cessation rate due to pregnancy was 70.2% (3516/5005) and the prevalence of smoking in pregnancy was 12.3% (1489/12,074). Multiparity was associated with less odds of smoking before pregnancy (OR: 0.79; 95% CI: 0.73-0.85), whereas advanced maternal age (OR: 1.17; 95% CI: 1.07-1.27) and obesity (OR: 1.44; 95% CI: 1.29-1.6) were associated with higher odds of smoking before pregnancy. Smoking prevalence in pregnancy was lower in women that conceived via assisted reproductive techniques (ARTs) (OR: 0.52; 95% CI: 0.38-0.70) and higher in cases of multiparity (OR: 1.12; 95% CI: 1.008-1.26) and maternal obesity (OR: 1.55; 95% CI: 1.20-2.00). Conception via ARTs was associated with higher odds of smoking cessation (OR: 1.9; 95% CI: 1.38-2.69), whereas multiparous (OR: 0.7; 95% CI: 0.62-0.8) and obese women (OR: 0.72; 95% CI: 0.61-0.85) were less likely to quit smoking. Pregnancy is a strong motivator for women to quit smoking, especially in primiparous women and those undergoing ARTs. Our findings highlight the need for more consistent smoking prevention and health promotion strategies in Greece as a very high proportion of women smoke before pregnancy and a substantial proportion continue in pregnancy.