Skip to content
My WebMD Sign In, Sign Up

Birth Control Health Center

Font Size

Which Birth Control Pill Is Safest?

Researchers Find Differences in Blood Clot Risk in Different Oral Contraceptives

Second Opinion

The new research confirms previous findings and adds new information, says Ricardo Azziz, MD, chairman of obstetrics and gynecology at Cedars-Sinai Medical Center in Los Angeles, who reviewed the data for WebMD.

"We know that the combination pills [with estrogen and a progestin] do increase the risk of thrombosis," he says. It's also known, he says, that women with an inherited clotting disorder are at higher risk for having a clot if they take the pill.

But, he adds, overall ''the chances of any woman taking birth control pills having a deep vein thrombosis is low. Of 10,000 women using the pill, in one year's time six will have a deep vein thrombosis."

What's also known, he says, is "the longer you use it the less chance of having a DVT." That might be due to what experts call "selection bias" -- women who had a problem discontinued using the pill and those who remain on it are simply less prone to blood clotting problems.

What is also important to understand, Azziz says, is that even if the risk of blood clots from one type of pill is twice or more that of another, "We are talking about twice the risk for something that is quite rare to begin with."

Women shouldn't go off the pill based solely on the new findings, he says. What is crucial, he says, is for a woman's doctor to prescribe the birth control pill that's best for her, the one that will be linked with the least side effects. "Some patients will do better on some pills than others," he says.

Starting with the lower-dose estrogen pills and the ones with progestins found linked with the least risk is wise, he says. To start with, he suggests pills with levonorgesterol or norethisterone and a low dose of estrogen.

The risks associated with not taking the pill, including unwanted pregnancy and pregnancy complications, may be higher than the risk associated with its use, Azziz says.

Oliver Renner, a spokesman for Bayer Schering Pharma in Berlin, which makes oral contraceptives, says the company is in the process of evaluating the data and needs time to respond.


Today on WebMD

Birth Control Options
mother and daughter talking
Period Questions
Condom Quiz
Forgot To Take Your Birth Control Pills
pelivic pain slideshow
Birth Control Pills Weight Gain
Ortho Evra Birth Control Patch
Comparing Birth Control Pill
New Birth Control Pill
HPV Vaccine Future
Young couple holding hands