MONDAY, Dec. 15, 2003 (HealthDayNews) -- Young women who have survived breast cancer can become pregnant without increasing the odds their cancer will come back, new research finds.
A study, which will appear in the Feb. 1 print issue of Cancer and in its online edition on Dec. 15, followed young women who were successfully treated for breast cancer for almost 25 years. The researchers conclude that if a woman still has healthy ovarian function, there is no reason she shouldn't try to have a baby if she wants one.
"If [breast cancer survivors] want to have a baby, they should not be afraid that the cancer will recur," says study author Dr. Aman Buzdar, a professor of medicine at the University of Texas M.D. Anderson Cancer Center in Houston.
Other cancer experts say this study is good news for women who want to conceive after having breast cancer.
"For years, the controversy that women shouldn't get pregnant because it would produce estrogens that might trigger breast cancer has drifted around," says Dr. David Decker, an oncologist at William Beaumont Hospital in Royal Oak, Mich. "This study reassures women that it's safe to get pregnant."
"Once you've had cancer, you're always concerned that it may come back, so this is very reassuring data that pregnancy does not increase the risk of it coming back," notes Dr. Jay Brooks, chief of hematology and oncology at Ochsner Clinic Foundation Hospital in New Orleans.
More than 200,000 women are diagnosed with breast cancer in the United States every year, according to the study. About one-quarter of those cancers occur in women who haven't reached menopause yet.
Buzdar and his colleagues followed 383 breast cancer survivors between 1975 and 1998. All of the women were less than 35 years old at the time they were treated for their cancer. All were treated with chemotherapy at the M.D. Anderson Cancer Center.
Forty-seven women -- or 13 percent -- became pregnant during the study time period. Thirty-two of those women went on to have full-term pregnancies.
Those who had a successful pregnancy were slightly more likely to have been diagnosed with stage I or stage II breast cancer than more advanced cancer. Women who had babies were also more likely to be under 30 at the time of diagnosis.
Women who experienced a pregnancy had a 23 percent breast cancer recurrence rate, while 54 percent of the women who didn't get pregnant saw their cancer come back.
Buzdar says this difference is statistically significant.
Decker says it's possible there may be a selection bias in the study, because it may be the women who got pregnant were the ones who were the healthiest ones in the group.
However, he adds that if he has a young patient, he tells them that future pregnancies are safe.
Buzdar says the low rate of pregnancy in this group of women may be due in part to doctors advising against pregnancy in the past. In women over 35, chemotherapy sometimes induces premature ovarian failure, but Buzdar says younger women's bodies are often more resilient and it's more likely a young woman will retain ovarian function after chemotherapy. Decker adds chemotherapy can also temporarily stop a woman's menstrual cycle.
For young women facing breast cancer treatment, Brooks says their primary focus should be on themselves rather than their future fertility. "The first job is to treat you to give you every opportunity to be alive," he says.