I am 25 weeks pregnant. During my 18-week ultrasound, a large gallstone was discovered. What can you tell me about gallbladder problems in mid-pregnancy?

--Minda

Gallbladder problems, including gallstones, increase in pregnancy. The gallbladder may not empty as efficiently during pregnancy, leaving behind "sludge" that can become the basis for the formation of a stone; sludge is seen in about 25 to 30 percent of pregnant women who have ultrasound tests of their gallbladders. Anywhere between 2.5 and 10 percent of pregnant women will actually have gallstones, most of which do not cause symptoms.

A small number of women -- about 1 in 1,000 -- will have gallstones that do cause problems. The stone or stones may block a duct that empties the gallbladder, causing pain under the right rib cage. Often the pain is worse after a fatty meal, because the gallbladder produces more bile to help the body digest such foods. Nausea, vomiting and loss of appetite are other common symptoms. Sometimes a bacterial infection can occur, and a woman can be significantly ill, with fever in addition to the above symptoms.

Depending on the severity of the symptoms and how far along you are in your pregnancy, the treatment can vary. Sometimes avoiding certain foods is all that is required. Sometimes hospitalization is necessary, with intravenous fluids and painkillers. If attacks are severe or frequent, or if infection is present, then surgery is the treatment of choice. Most of the time today, the gallbladder can be removed by laparoscopy, using several tiny incisions instead of one big, painful one. In the latter stages of pregnancy, the uterus may be in the way and the older "open" approach, with a large incision, must be used. The best time to do surgery is the second trimester; risk of miscarriage from surgery is low, and the uterus is usually still small enough not to interfere with the laparoscopic approach.