Fibroids in the uterus (see Fibroids), which are relatively common noncancerous tumors, may increase the risk of preterm labor, abnormal presentation of the fetus, a mislocated placenta (placenta previa), and repeated miscarriages. Rarely, fibroids interfere with the movement of the fetus through the vagina during labor.

Last full review/revision December 2008 by Sean C. Blackwell, MD