Timing of smoking cessation before and during pregnancy and risk of gestational diabetes: A systematic review

The timing of smoking cessation is a critical modifier of gestational diabetes mellitus risk. Continued smoking after the first trimester is associated with increased metabolic risk, whereas early cessation before or during early pregnancy appears beneficial. These findings underscore the importance of timing-sensitive smoking exposure assessment in both epidemiological research and clinical counseling of pregnant women. However, these findings are based on a very limited evidence base, as only four observational studies met the inclusion criteria, substantially restricting the strength and generalizability of inferences.