Pregnant women who are overweight in the first trimester of pregnancy are more likely to have longer pregnancies and more complications.
Doctors in the United Kingdom analyzed data from women who gave birth between 1998 and 2002. They found that women with higher body mass indexes during the first trimester, as well as those with greater weight gain during pregnancy, had pregnancies longer than 40 weeks.
Being overweight was also associated with a greater chance stillbirth, gestational diabetes and need for Cesarean delivery.
This study is in the British Journal of Obstetrics and Gynecology.