Study questions herbs and infertility

WASHINGTON (AP) -- Scientists have uncovered a new worry about some of the most popular herbal remedies: they could cause infertility, or genetically damage sperm.

 Many women who are pregnant or trying to conceive carefully avoid taking prescription and even over-the-counter medications for fear they could endanger their chances of a healthy pregnancy.

 But herbs and other dietary supplements are advertised as "natural," implying that they're safe, non-drug remedies. In fact, many powerful prescription drugs were derived from plants, and many of the herbs sold in health-food stores and supermarkets also can have powerful actions and side effects.

 The new study by researchers at Loma Linda University suggests that the side effects of some of popular herbs -- St. John's wort, echinacea and ginkgo -- could include blocking conception. The study also uncovered suggestions of genetic damage to sperm, raising questions of whether such changes could cause problems for a resulting baby.

 The test-tube study is not proof that couples trying to conceive should avoid taking herbs.

 Lead researcher Dr. Richard Ondrizek stressed that laboratory research doesn't always accurately predict what happens in the human body. Nobody has ever tested actual herb users to see if the products concentrate in their sperm or eggs -- the key to knowing if there's any risk.

 Still, "this is a very important study that could provide important information to patients suffering from infertility," said Alan DeCherney, editor of Fertility and Sterility, the journal that published the herb study this month.

 An infertility specialist says he already warns couples to avoid such products while trying to conceive, because it's better to be safe than sorry.

 "I do tell folks to stop taking them when they're doing fertility treatment," said Dr. Eric Widra of Georgetown University.

 Patients constantly ask him if "there isn't something I could go to the health food store and get that's going to help me," he said. "They think natural is good."

 The Loma Linda researchers subjected four herbs to fertility testing similar to that medications undergo, mixing them with human sperm and hamster eggs. Tested were St. John's wort, which treats mild depression; echinacea, purported to strengthen the immune system and fight colds; ginkgo, a purported memory enhancer; and saw palmetto, which can treat older men's enlarged prostates.

 In the Loma Linda testing, only saw palmetto did not damage sperm or eggs.

 St. John's wort completely blocked the ability of sperm to penetrate eggs, and echinacea and ginkgo reduced that ability. Eggs treated with ginkgo "were visibly degenerated," the researchers reported.

 Echinacea and St. John's wort also caused DNA changes reducing sperm viability.

 Loma Linda researchers used doses that are a fraction of those recommended on the herbs' labels. But because no one knows if the herbs actually wind up in their sperm or eggs, more research must be done to see if they really could impede fertility.

 "What's most important about this study is it illustrates something that gets lost in the discussion of herbal preparations," Widra said. "Despite an apparent high degree of willingness among people to try these things, there's very little science to back up their safety."