What are the risks of uterine fibroids during pregnancy?

Some studies have shown an increased risk of pregnancy complications in the presence of fibroids, such as first trimester bleeding, breech presentation, placental abruption, and problems during labor. Fibroids have also been associated with an increased risk of cesarean delivery. The size of the fibroid and its precise location within the uterus are important factors in determining whether a fibroid causes obstetric complications.