WORLD —Doctors and researchers in increasing numbers across the globe are questioning the safety of women taking birth control pills to prevent pregnancy.Last week, a Belgian study found that the pill causes artery-clogging plaque, which increases the risk of heart disease and a study published in the British journal Lancet reiterated the known link between the Pill and cervical cancer.

Lancet study author Jane Green, an epidemiologist at the University of Oxford, and her colleagues reported that women who take the Pill for five years or more are twice as likely to develop cervical cancer as those who do not.

“I fear that this paper, well intentioned as it is, will convey the wrong message to the public,” says Dr. Diane Harper, a professor of women’s and gender studies at Dartmouth College in Hanover, N.H. “The message that would be wrong for people to conclude is that prolonged use of oral contraceptives causes cervical cancer — only HPV causes cervical cancer.”

Some doctors say the link between the Pill and cancer may be due to increased sexual activity. They note women who are on the Pill may be more sexually active, and thus more likely to be infected with HPV.

In addition, women who take birth control pills may be less likely to use condoms, which means that they are not protected from HPV.

“We know that cervical cancer is caused by the HPV virus, and we also know that the transmission of HPV is reduced with condom use,” said Dr. Lisa Jones, a gynecologist at the New Bedford Community Health Center in Massachusetts to ABC News. “The important variable is the lack of condoms, not the presence of birth control pills.”

Until more conclusive research shows a direct connection between the Pill and cervical cancer, most doctors and researchers seem to agree that women should not be scared off from using the Pill as birth control. Taking the Pill might actually provide some cancer protection for women. Oral contraception has been shown to reduce the risk of ovarian cancer by 40-percent, and past studies have shown that the Pill reduces cancer of the womb by as much as 50-percent.

“This research adds to the picture of the overall risks and benefits associated with taking the Pill,” says Green. “The small increase in risk of cervical and breast cancer is well-outweighed by the reduced risk of cancer of the ovaries and womb.”