Birth Control Pills not Linked to Birth Defects: Study

The Guttmacher Institute reports that in the United States alone, the largest proportion of American women use the pill as contraceptive (28%), with tubal sterilization following closely (27%), and finally, the condom at 16%. Statistics also show that sterilization is the most common method used by black and Hispanic women while white women commonly use the pill.

A new study published in the medical journal "BMJ" conducted by researchers from the United States and Denmark show that te use of contraception shortly before or during pregnancy are unlikely to result in birth defects, TIME reports. Researchers used national medical registries to collect and analyze data from Denmark from 1997 to 2011 on all live births, birth defects, and mothers' medical conditions. The results showed that in over 880,000 births, 2.5% of them had a birth defect such as a cleft palate or an arm or leg defect.

HealthDay reports that researchers led by Brittany Charlton, an instructor in the department of epidemiology at Harvard's T.H. Chan School of Public Health in Boston, found that for every 1,000 births, 25.1 infants of mothers who never took the pill had birth defects, as well as 25.0 of infants of mothers who did use birth control pills over three months before the pregnancy. The rate of having a birth defect in their babies was 24.9% in mothers who used birth control pills within 90 days of becoming pregnant, and 24.8% among mothers who used the pill before being aware of the pregnancy.

"Women who become pregnant either soon after stopping oral contraceptives, or even while taking them, should know that this exposure is unlikely to cause the fetus to develop a birth defect," Charlton said. "This should reassure women as well as their doctors."

NPR reports that epidemiologist Kim Waller of the University of Texas Health Science Center at Houston School of Public Health, wrote a 2010 study analyzing oral contraceptive use and 32 categories of birth defects. Like this study, hers found no links between the usage of the pill and most kinds of birth defects. However, results showed a statistically significant risk of the same heart problem in babies born to women who used the pill during the first trimester.

Charlton said, "The prevalence of birth defects was consistent across each of the oral contraceptive groups as well as when we added in pregnancies that ended as stillbirths or induced abortions. Similarly, the results were also consistent even when we broke down the birth defects into different subgroups, like limb defects."

Dr. Diane Horvath-Cosper, a fellow of the American College of Obstetricians and Gynecologists, told NPR that this new study "provides me with a lot more convincing evidence that there's no link between oral contraceptives and birth defects."