It sounds far-fetched - sticking needles in women to help them become pregnant- but a scientific review suggests that acupuncture might improve the odds of conceiving if done right before or after embryos are placed in the womb.

The surprising finding is far from proven, and there are only theories for how and why acupuncture might work. However, some infertility specialists say they are hopeful that this relatively inexpensive and simple treatment might ultimately prove to be a useful add-on to traditional methods.

"It is being taken more seriously across our specialty," and more doctors are training in it, said Dr. William Gibbons, who runs a fertility clinic in Baton Rouge, La., and is past president of the Society for Assisted Reproductive Technology. "I have not seen proof ... but we wouldn't mind at all" if it turned out to work, he said.

The analysis was led by Eric Manheimer, a researcher at the University of Maryland School of Medicine, and paid for by a federal agency, the National Center for Complementary and Alternative Medicine. Results were published Friday in the British medical journal, BMJ.

Acupuncture involves placing very thin needles at specific points on the body to try to control pain and reduce stress. In fertility treatment, it is thought to increase blood flow to the uterus, relax the cervix and inhibit "fight or flight" stress hormones that can make it tougher for an embryo to implant, Manheimer said.

The analysis pools results from seven studies on 1,366 women in the United States, Germany, Australia and Denmark who are having in vitro fertilization, or IVF. It involves mixing sperm and eggs in a lab dish to create embryos that are placed in the womb.
Women were randomly assigned to receive IVF alone, IVF with acupuncture within a day of embryo transfer, or IVF plus sham acupuncture, in which needles were placed too shallowly or in spots not thought to matter.

Individually, only three of the studies found acupuncture beneficial, three found a trend toward benefit and one found no benefit. When results of these smaller studies were pooled, researchers found that the odds of conceiving went up about 65 percent for women given acupuncture.

Experts warn against focusing on that number, because this type of analysis with pooled results is not proof that acupuncture helps at all, let alone by how much. IVF results in pregnancy about 35 percent of the time. Adding acupuncture might boost that to around 45 percent, the researchers said.

The authors include doctors from the Netherlands and Georgetown University in Washington, D.C. One is an acupuncturist but had no role in any studies that were analyzed.