Come again?

German scientists find surge in prolactin -- a libido-decreasing hormone -- after orgasm.

By Jack Boulware

Aug 25, 2000 | Ever feel lazy after sex? Find it difficult to get it together for another go-round? Are you basically good for once around the block and then it's nap time? It's not surprising news for most of us, but two doctors in Germany recently became very excited about this phenomenon, because they now have proof! Proof that human libido decreases after orgasm!

The place: the University of Essen's Institute of Medical Psychology. The researchers: Dr. Manfred Schedlowski and Dr. Michael Exton. The goal: to measure levels of the hormone prolactin, which is produced by the body following an orgasm. The subjects: 10 women who masturbated until they achieved that special feet-to-the-ceiling feeling.

Let's look at this research more closely. Ten women are invited into the (one assumes) hallowed halls of the institute in Essen. Each is ushered into a room and gets attached to some sort of device to measure her hormone levels. Then the 10 women remove their paper hospital gowns, lie on their beds and begin to masturbate, slowly at first, because surely the surroundings are strange and clinical, but then gradually relaxing into the fantasy, and that unmistakable feeling begins to build. Each woman uses a secret method of stimulation known only to her and never revealed to others, until the tingling grows and grows and then erupts into a full-blown, rootin'-tootin' flood of hallelujahs, during which the hallways fill with the sounds of 10 women panting, sighing, gasping, perhaps shrieking, "Oh God, oh God, yes, yes, YES" (or the German equivalent).

The machines register absurd levels of hormone surges, and then each woman lies back on the bed, residual shudders here and there, and then, perhaps, Schedlowski and Exton burst into the rooms, eagerly inspect the hormone readings and shake their fists to the sky in victory.

Sexual research is in many ways its own reward.

"What was interesting was the large increase in prolactin in response to the orgasm," Exton told Reuters Health. "We saw levels (of prolactin) increase by 100 percent and maintain prominent levels for up to an hour after orgasm," he said. The prolactin hormone is released by the pituitary gland and primarily contributes to decreased libido and the production of milk in women after pregnancy. Men also produce prolactin, and previous tests conducted on male subjects (i.e., a hallway full of men in small rooms, clutching tissues and grunting, "Oh yeah, baby, do it, yeah!") concluded that the men also experienced a decrease in libido. Big surprise there. Exton added that although prolactin brings down libido in both sexes, the results were unique because levels of prolactin were actually higher in the women.

"We believe that the prolactin response to sexual arousal may be some kind of negative feedback to the brain -- meaning that it regulates sexual arousal after orgasm," said Exton. "What we are now investigating is whether or not the acute increase of prolactin regulates libido and sexual function."

When asked about the possibility of a drug that could increase orgasms by inhibiting the production of prolactin, Exton replied, "This is not really part of our research scope, but I think there would be numerous potential physiological uses for such a drug."

The 10 female test subjects were last seen leaving the institute, walking at a leisurely pace and smiling to themselves.

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