New government guidelines suggest that women who have recently given birth and are older than 34 or who had a C-section steer clear of certain types of oral contraceptives.
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Scientists at the Centers for Disease Control and Prevention concluded that birth control pills containing estrogen could boost the risk of a blood clot when taken by some new mothers within six weeks of a baby’s birth.
All new moms are advised not to take these types of oral contraceptives in the first three weeks following delivery.
Blood clots, if they travel to the lungs or the brain can lead to serious complications, including stroke, shortness of breath, or even death, said one of the guideline’s authors Dr. Naomi Tepper, an ob-gyn in the CDC’s division of reproductive health.
Tepper and her colleagues analyzed a host of recent studies to determine whether birth control pills raised the risk of blood clots in new moms.
“The evidence we looked at showed that the risk was really much higher than we previously thought,” Tepper said. “That is what spurred the change in recommendations.”
The risk of blood clots in women of reproductive age is normally low. But it goes up significantly when women are pregnant and stays high during the first six weeks following delivery — about 50 out of 10,000 recently delivered women develop a clot each year.
That’s because pregnancy leads to changes in clotting factors, said Dr. Beatrice Chen, an assistant professor and director of Family Planning at the University of Pittsburgh. “Pregnancy causes a decrease in the body’s natural blood thinners and an increase in clotting,” Chen said. “That’s something that happens to all women who are pregnant.”
The risk of blood clots during the first six weeks after a baby is born goes even higher if women are older or have had C-sections, Chen said. When you add in the extra risk of blood clots associated with estrogen use, then the risks to the new moms outweigh the benefits of using birth control pills to prevent pregnancy.
That doesn’t mean that women should skip contraception altogether, Chen said.
Studies have shown that women and babies do better if there is at least a year between the birth one child and the conception of the next.
“If there’s less than a year in between, you can have problems with the next pregnancy, including low birth weights and pre-term births,” Chen explained.
Up until six weeks, women in the high-risk category could us implants or injections that contain progestin only, Tepper said. IUDs would also be safe, she added.
The last set of guidelines, which were published in 2010, suggested that women would be safe taking birth control pills with estrogen three weeks after delivery of the baby.
The current guidelines still warn against any woman taking pills with estrogen during the first three weeks after delivery. In a departure from earlier guidelines they advise against using this type of contraception for another three weeks after delivery in women with certain risk factors, such as a C-section.
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