The study was published in the Annals of Noninvasive Electrocardiology (5/3/13) and found that women who took fourth-generation oral contraceptives - those are the contraceptives that contained drospirenone - had an increased risk of a significantly longer corrected QT interval than women who did not use oral contraceptives. Conversely, women using earlier generation contraceptives had a shorter corrected QT interval.
According to MedPage Today (5/8/13), a prolonged corrected QT interval can be a sign of an increased risk of sudden cardiac death. Even after researchers accounted for age, race and other factors that can lead to prolonged corrected QT intervals, they found an increased risk of prolonged QT in women using drosperinone-containing birth control.
“Shorter QTc [corrected QT interval] is seen with first and second generation OC [oral contraceptives] while fourth generation OC use has a lengthening effect on the QTc. Careful examination of adverse event rates in fourth generation OC users is needed,” researchers wrote.
Of concern are women who might also be taking other drugs that also prolong the corrected QT interval, such as some antibiotics.
READ MORE YASMIN BIRTH CONTROL LEGAL NEWS
In April 2012, the US Food and Drug Administration (FDA) issued a Drug Safety Communication, warning that some studies suggested birth control pills that contained drospirenone carried a higher risk of blood clots than those that contained a different progestin. At the time, the FDA noted that although the studies did not provide a consistent estimate of the difference in risk between fourth-generation and earlier contraceptives, the risk could be as high as three times greater in oral contraceptives that contain drospirenone.
Some studies did not find an increased risk of blood clots in fourth-generation oral contraceptives. There is an increased risk of blood clot in any oral contraceptive.