In January, drug regulators in France pulled a contraceptive by Bayer, called Diane 35, off the market because it was purported to cause blood clots and strokes. In France, the drug is approved only as an acne medication, not a contraceptive, although it is approved for birth control in many other countries. The French National Agency for the Safety of Medicine and Health Products (ANSM) requested a review by the European Medicines Agency, which has just come back with its final statement after reviewing all data. The EMA announced that it has no problem with use of the drug as an acne medicine.

"EMA's Pharmacovigilance Risk Assessment Committee (PRAC) concluded that the benefits of Diane 35 and other medicines containing cyproterone acetate 2 mg and ethinylestradiol 35 micrograms continue to outweigh their risks for the treatment of moderate to severe acne," the report stated. The report went on to state that the drug and its generics should only be used when other treatments have failed, and that medical professionals should take precautions to minimize the risk of clots. "These medicines should be used solely in the treatment of moderate to severe acne... in women of reproductive age," the report continued.

The reason for the investigation was warranted by the recorded deaths of four women in the past 25 years from blood clot-related health issues. An additional 125 women were also documented to have had blood clots due to the oral contraceptive.

Oral contraceptives have been used for over 50 years around the world, allowing women to control ovulation in order manage pregnancies. Many of the original pills used a combination of estrogen and estradiol, two hormones that would overpower the body's natural production and control the fertility cycle. More modern drugs use synthetic hormones and carry the same, if not more, risk of clotting events compared to the original formulation. In 2012 the U.S. Food and Drug Administration updated the labeling protocol for drospirenone-based oral contraceptives (marketed under the names Yasmin, Yasminelle, Yaz, Beyaz, Ocella, Zarah, and Angeliq), requiring a warning of the increased risk of blood clots.

The U.S. Food and Drug Administration (FDA) has not approved any hormone-based contraceptives for the sole treatment of acne, but has approved three, Ortho Tri-Cyclen, Estrostep, and YAZ, for the treatment of moderate to severe acne in women who are at least 14-15 years old and are using the pill as contraception as well. More than 100 million women around the world currently use oral hormone-based contraceptives to prevent unwanted pregnancy, and if used properly, they can be more than 99 percent effective in preventing pregnancy.

The Bayer drug is approved and prescribed in the UK as Dianette and as Diane-35 in Canada, but is not approved for use in the United States. No form of the drug containing the active ingredient, cyproterone, has been approved by the U.S. FDA. The drug by itself does not increase clotting events, but when combined with ethinylestradiol, a form of estrogen used in contraceptives, the risk of blood clots increases six to seven fold compared to women not on contraception.