During pregnancy, a disorder that requires surgery involving the abdomen may develop. This type of surgery often slightly increases the risk of preterm labor and can cause a miscarriage, especially early in pregnancy. Thus, surgery is usually delayed if possible. However, if necessary, surgery should proceed without delay and is still usually reasonably safe.

Appendicitis: If appendicitis develops during pregnancy, surgery to remove the appendix (appendectomy) is done immediately because a ruptured appendix may be fatal. An appendectomy is not likely to harm the fetus or cause a miscarriage. However, appendicitis may be difficult to recognize during pregnancy. The cramping pain of appendicitis resembles uterine contractions, which are common during pregnancy. The appendix is pushed higher in the abdomen as the pregnancy progresses, so the location of pain due to appendicitis may not be what is expected.

Ovarian cyst: If an ovarian cyst persists during pregnancy, surgery is usually postponed until after the 14th week of pregnancy. The cyst may be producing hormones that are supporting the pregnancy and often disappears without treatment. However, if a cyst or another mass is enlarging, is very tender, or has certain characteristics (seen on an ultrasound), surgery may be necessary before the 14th week. Such a mass may be cancerous.

Obstruction of the intestine: During pregnancy, a blockage (obstruction) in the intestine can be very serious. If obstruction leads to gangrene of the intestine and peritonitis (inflammation of the membrane that lines the abdominal cavity), the woman may miscarry and her life is endangered. Exploratory surgery is usually done promptly when pregnant women have symptoms of intestinal obstruction, particularly if they have had abdominal surgery or an abdominal infection.

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