Feferkorn I, Badeghiesh A, Mills G, et al. - Using data from the HCUP-NIS over 11 years from 2004 to 2014, researchers conducted this retrospective population-based study to determine if there is an association between smoking and pregnancy complications in pregnant women with polycystic ovarian syndrome (PCOS). Pregnant PCOS women who smoked were compared with pregnant PCOS women who did not smoke. A second comparison was made between pregnant smokers who had PCOS and those who did not. Six hundred thirty-one of the 443,590 women who smoked during pregnancy and the 14,882 women with PCOS were both smokers and PCOS patients. In women with PCOS, there was a significant link between smoking and gestational diabetes mellitus.