Skip to content

Birth Control Health Center

Font Size

Ortho Evra Patch: Clot Risk Updated

Label Adds Details From 2 Conflicting Studies on Nonfatal Blood Clots
WebMD Health News
Reviewed by Louise Chang, MD

Sept. 20, 2006 -- The Ortho Evra patch is getting new labeling with more information on the risk of nonfatal blood clots associated with the patch.

The clotting risk isn't new, and the patch's warning about that risk isn't being strengthened.

The label change simply adds information from two observational studies, publicized by the FDA in February, about clotting risk in women using the patch or birth control pills containing 35 micrograms of estrogen.

The FDA's Daniel Shames, MD, spoke to reporters about Ortho Evra.

Shames is the acting deputy director of the Office of Drug Evaluation III at the FDA's Center for Drug Evaluation and Research.

"We still believe that the risk-benefit profile is appropriate for this particular contraceptive and it's safe and effective when taken with the appropriate label indication," Shames says.

He says the FDA is publicizing the label change to provide information.

"This is consistent with our policy to try to give information as soon as we know it when we think it's reliable information, even at times when we cannot make a specific change in our recommendations," Shames says.

Risk Not New

Ortho Evra, like other hormonal contraceptives, already warned users "not to smoke and not to use the product if they have a history of blood clots, stroke, heart attack, or certain cancers," Shames says.

The patch also already encouraged women "to discuss with their health care professional whether Ortho Evra was the right method of contraception for them," says Shames.

A statement from Ortho Evra's maker, Ortho Women's Health & Urology, encourages Ortho Evra users to consult their doctors with any questions. The company, a branch of Ortho-McNeil Pharmaceutical, also pledges more studies on the topic. Ortho-McNeil is a WebMD sponsor.

Conflicting Results

The two studies included data from two insurance companies and had conflicting results, says Shames.

The data covered 400,000 to 500,000 women aged 15-44 using the patch or birth control pills containing 35 micrograms of estrogen.

The studies were purely observational, meaning that women weren't assigned to use either type of birth control. So they didn't directly test the patch as a clot cause.

The first study showed no increased risk of nonfatal clotting events -- such as pulmonary embolisms (blood clots that travel to the lungs) or deep vein thromboses (blood clots that can occur in the legs' deep veins) -- with the patch compared with birth control pills.

But the second study, which hasn't been published yet, showed that patch users were twice as likely as pill users to get those nonfatal clots.

The results don't show the risk of fatal blood clots with either contraceptive.

'Very Small' Risk

"Even though the results of these two studies are conflicting, the result of the second epidemiologic study is consistent with the FDA's concern regarding the potential for Ortho Evra use to increase the risk of blood clots in some women," Shames says.

He points out that the increased risk is still "very small," rising from three to five per 10,000 birth control pill users to about six per 10,000 patch users in any given year.

Both studies were funded by the patch's maker and will be continued for another 1.5 years to two years, says Shames. The follow-up will also check on heart attack and stroke risk.

Since February, the second study's preliminary findings have been double-checked, with similar results, says Shames.

The Ortho Evra patch may expose up to 60% more estrogen than oral contraceptives containing 35 micrograms of estrogen, and that may mean a greater clotting risk. That fact has been on Ortho Evra's label since November 2005.

"Health care providers need to balance the risk of higher estrogen exposure with Ortho Evra against the chance of pregnancy if a contraceptive pill is not taken daily," Shames says.

Today on WebMD

Here's what to expect.
man opening condom wrapper
Do you know the right way to use them?
birth control pills
Here's what to do next.
doctor and patient
His and her options.
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