Maternal characteristics of women with gastric bypass prior to their pregnancy compared to all pregnancies registered in the Danish Fetal Medicine Database in 2008.

aContinuous normally distributed data were compared with Student's t-test and proportions between dichotomous outcomes were compared with χ2-square tests using two-sided p-values.bData on Smoking were missing in 4/387 women in the gastric bypass group and 677/57,368 in the general pregnant population.cBody mass index. Missing values on BMI in 8/387.dICSI, IVF and insemination, missing information on 9/387 in the gastric by pass group and 5214/57,368 in the general pregnant population.enot significant.