Common Benign Uterine Tumor May Complicate Pregnancy

June 1, 2000 -- A common type of uterine tumor may not be cancerous, but it can still cause pregnant women problems. The current issue of the journal Obstetrics and Gynecology reports that the tumors, commonly referred to as fibroids, increased the risk of bleeding during the first three months of pregnancy, separation of the placenta, breech delivery, and the need for a cesarean section.

Infants born to mothers who had fibroids were more likely to have a low five-minute Apgar score, a low birth weight, or a deformity, according to a review of birth records.

"The most important finding to me in this study is that fibroids do appear to increase the risk that women will suffer certain complications during their pregnancy, labor, and delivery," Gloria Coronado, MS, tells WebMD. Coronado is a project manager at the Fred Hutchinson Cancer Research Center in Seattle, and the study's lead author.

Coronado and colleagues studied more than 2,000 women with fibroids who had babies in Washington state between 1987 and 1993.

"Fibroids are extremely common," says Sandra Brooks, MD. "We know that about 50% of women over the age of 35 will have them, and as women delay childbearing until they are older, fibroids and their impact on pregnancy, labor, and delivery may become more of an issue." Brooks, who reviewed the study for WebMD, is assistant professor of obstetrics and gynecology at the University of Maryland School of Medicine, in Baltimore, and director of gynecologic oncology.

"I don't think this should scare anyone, however," she adds. "If a woman has been told she has fibroids, she needs to be examined regularly with a pelvic exam or ultrasound or both to see whether her fibroids are getting bigger. She may also want to keep this fact in mind as she plans her family."

Brooks says that fibroids do not necessarily produce problems in pregnancy, but they can, depending on their size and location. But don't despair. "If they are causing a problem, fibroids can be treated with medications or surgery or both," she says.

• Fibroids are benign tumors of the uterus, and they are extremely common, possibly occurring in half of all women over age 35.
• New research shows that fibroids may cause complications during pregnancy, such as bleeding during the first three months, separation of the placenta, and breech delivery.
• Fibroids do not always cause complications during pregnancy, but women with fibroids should be monitored regularly, and treated if necessary with medication or surgery.