In 1960, the FDA approved the birth control pill, liberating women in a number of ways. This allowed them to delay having a family in order to focus on education and career, and even to have sex outside of a traditional relationship, without the fear of being sucked into a humiliating tableau. Many historians say the advent of the pill launched the Sexual Revolution of the 1960’s, whose influence we are still feeling in dating apps, high rates of cohabitation, and in many countries, record low birth rates.

Since then, the pill has been blamed for all kinds of things, including increasing the risk of depression and dampening a woman’s sex drive. Consider the irony, as that which liberated women’s sexuality is considered the source of its suppression. But is it true? That’s an important question, and studies over the years have had less than straightforward results. It is also an important inquiry, as a lot of sex lives are on the line.

According to the CDC, 63% of reproductive age women in the US were on some type of birth control as of 2012. Of these, 28% were on the pill, making it the most popular form by far. That’s 10.6 million American women, to say nothing of those taking it elsewhere. Though it is commonly thought to suppress desire, a study recently published in the Journal of Sexual Medicine found the evidence inconclusive.

An analysis of past studies found conflicting results and many used inconsistent methodology, according to researchers. Some of the studies did not compare hormonal to non-hormonal forms of birth control, for instance. Others failed to account for the type of relationship a woman was in and what she and her partner consider normal. After all, the libido of both sexes varies widely from person to person. Investigators also contend that the effect on the pill on the female libido is “not well studied.”

Researchers at the University of Kentucky and Indiana University collaborated on this. Dr. Kristen Mark of the University of Kentucky led the study. It had two phases. Both looked at different kinds of contraceptives, hormonal and non-hormonal. They also examined the libidinal nature of the women’s male partners.

Though a sign of female sexual liberation, many believe that it also dampens the libido.

In the initial phase, Mark and colleagues looked at heterosexual couples who had been together for different lengths of time. The second phase looked at couples in long-term relationships. Though we see the sex drive as one sort of craving, the scientists say there are actually two kinds, solitary and dyadic. This is the difference between the libidinous feelings a woman has by herself versus the kind she has in the presence of her partner. To measure female libido, researchers employed a metric known as the Sexual Desire Inventory (SDI). This questionnaire measures desire cognitively, rather than behaviorally.

Over 900 participants took part. Dr. Mark and colleagues discovered that what type of contraceptive used had an impact on both forms of desire, at the outset. Those women on non-hormonal birth control had higher solitary libidos, over those using non-hormonal methods. Yet, those on hormone-based birth control reported higher levels of dyadic desire, over those using the non-hormonal forms.

Yet, when age, the age of the relationship, and other contextual information was accounted for, such differences vanished, suggesting that the context a woman was in played a far more substantial role than the type of contraceptive she used. The length of the relationship also had a greater impact. Examining individual couples solidified these findings. Other research has shown that some women see a boost in libido after starting the pill, while other find it dampens desire.    

Researchers found the age of the relationship, the woman’s age, and other contextual factors were more impactful to a woman’s libido than taking the pill.

Since the pill is most commonly used in long-term relationships, it may be prolonged monogamy that’s affecting the female libido, rather than the pill itself. It’s harder to keep the spark alive in a long-term relationship, and it’s easy to fall into a rut. Also, there are plenty other factors that can sap a women’s sex drive including stress, anxiety, a poor body image, relationship issues, a preoccupation with a difficult problem, her outlook on intimacy, and more. Women who are pregnant or breastfeeding also see a drop in sex drive. Remember that while most men are visually stimulated, women are generally turned on by being desired. So the ardor of her partner can boost libido, while its absence may shrink it.

Dr. Mark called this a myth-busting study. She said, "Sometimes women are looking for something to explain changes in their sexual desire, which is not fixed throughout their life.” The pill, in this case, may be an easy target. Dr. Mark is now looking into what the contextual elements are and how they affect the female sex drive. “By continuing to unravel the mysteries behind the inaccurate anecdotes out there,” she said, “I hope we can help women understand – and address – changes in their sexual desire."

To learn more surprising findings about the birth control pill, click here: