Does baby powder cause cancer? Another jury says yes.

WHAT RESEARCH SHOWS

The biggest studies have found no link between talcum powder applied to the genitals and ovarian cancer. But about two dozen smaller studies over three decades have mostly found a modest connection — a 20 percent to 40 percent increased risk among talc users.

However, that doesn’t mean talc causes cancer. Several factors make that unlikely, and there’s no proof talc, which doesn’t interact with chemicals or cells, can travel up the reproductive tract, enter the ovaries and then trigger cancer.

One large study published in June 2016 that followed 51,000 sisters of breast cancer patients found genital talc users had a reduced risk of ovarian cancer, 27 percent lower than in nonusers. An analysis of two huge, long-running U.S. studies, the Women’s Health Initiative and the Nurses’ Health Study, showed no increased risk of ovarian cancer in talc users.

WHAT EXPERTS SAY

If there were a true link, Dr. Hal C. Lawrence III says large studies that tracked women’s health for years would have verified results of the smaller ones.

“Lord knows, with the amount of powder that’s been applied to babies’ bottoms, we would’ve seen something,” if talc caused cancer, said Lawrence, vice president of the American College of Obstetrics and Gynecology.

The National Cancer Institute’s Dr. Nicolas Wentzensen says the federal agency’s position is that there’s not a clear connection.

“It is very hard to establish causal relationships,” he said, adding, “A lot of ovarian cancers occur in women who have never used talc, and many women have used talc and not gotten ovarian cancer.”

Research director Elizabeth Ward of the American Cancer Society says it is unusual to have so much discrepancy between studies. “The risk for any individual woman, if there is one, is probably very small,” Ward said.