Washington ? Risks of blood clots in legs and lungs are twice as high for women using the birth-control patch instead of the pill, according to a study reported by the drug maker and the Food and Drug Administration.

Dr. Daniel Shames of the FDA said Friday the new findings didn’t require immediate action by the government, but he urged concerned women to discuss the risk with their physicians.

One new study found users of the Ortho Evra patch had twice the risk of clots compared with women taking birth-control pills, although a second analysis found no difference in risk between the two forms of birth control.

“For some people, the patch may be better because some people don’t reliably take the pill or don’t want to take the pill or forget the pill,” Shames said. “So the patch does offer them some alternative for contraception.”

“On the other hand, we need to interpret what these results mean,” he said. “But these results are preliminary, so we can’t make hard comments about it.”

The results of the two studies were made public Thursday by the patch’s manufacturer, Ortho Women’s Health & Urology. Since the patch went on sale in 2002, more than 4 million women have used it.