Antenatal characteristics according to pre-pregnancy body mass index.

Note: BMI = Body mass index; SD = Standard deviation* Unless stated otherwise†p value indicates statistical difference between each BMI category and reference category for the related characteristica At the beginning of actual pregnancyb During actual pregnancyc Refers to a previous history of illness or surgery to breastd Number of months of breastfeeding experimented by women with one or more previous children. Refer exclusively to multiparous women (n = 3451)Antenatal characteristics according to pre-pregnancy body mass index.