A big O feels awesome—but does it affect fertility? We ran the science by ob-gyns.

By Madeleine Burry
May 01, 2018

There's no question why men orgasm: Those powerful muscle contractions are like rocket fuel for sperm, powering them into the female reproductive tract where ideally they'll fertilize an egg. What's still something of a mystery, however, is why women climax as well.

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Sure it's super pleasurable, but the female orgasm isn’t required for pregnancy, and plenty of couples conceive without it. But some research suggests that having an orgasm might slightly boost your chances of conception. Here's the science, plus what ob-gyns have to say about it.

Introducing the “upsuck” theory 

The upsuck hypothesis, coined in the early 1900s, has it that as a woman climaxes, her uterine muscles act like a vacuum—sucking up sperm to help them journey through the vagina. “When a woman orgasms, strong muscular contractions help propel sperm through the cervix and uterus, placing them in the fallopian tube where fertilization occurs,” explains Sherry Ross, MD, ob-gyn in Santa Monica, California and author of She-ology: The Definitive Guide to Women's Intimate Health.

Dr. Ross calls this theory controversial—and recent research to validate it has been inconclusive. One study found that when a woman reaches orgasm a minute before or up to 45 minutes after her partner ejaculates, it results in higher levels of sperm retention than if she didn't orgasm during that time frame (or at all).

Another study concluded that the female orgasm has “little or no effective role in the transport of spermatozoa in natural human coitus.” And a third, large study found that controlling for both a relationship's length and how often sex occurred eliminated any correlation between orgasm rate and the number of children a couple has.

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Many ob-gyns aren't convinced

Other doctors, however, are skeptical of the upsucking effect on pregnancy. “I am sorry to disappoint,” says Adeeti Gupta, MD, FACOG, founder of Walk IN GYN Care in Queens, New York. “Theories of female positions or the ability to achieve an orgasm have nothing to do with conception,” says Dr. Gupta, adding that conception comes down to biology.

“If the uterus and tubes…and the small little cells in the lining of the cervix and the vagina are working right so as to gently nudge the swimmers up the cervical canal into the uterus and then into the fallopian tube, and the eggs are forming and being released at the right time, then with the alignment of all these perfect conditions, you will get pregnant, no matter [if you have an] orgasm or not,” she says.

Don't stress about it—that can effect fertility

When you’re trying to conceive, so many factors can be a source of tension—and it's tension that may be a roadblock to conception. Don’t let your orgasm join the list of stressors. While climaxing may help, it’s not a prerequisite to pregnancy, says Dr. Ross.

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Stress, says Dr. Gupta, is a known fertility killer. “Stress increases the cortisol levels which in turn can cause a complicated feedback loop of causing female hormone imbalance, affecting ovulation and thus affecting conception,” she says. Dr. Ross agrees. "The relaxation effect of an orgasm helps in the babymaking process," she explains.

So if you're trying for a baby and you do orgasm, wonderful! It certainly can't hurt. But if you don’t hit that high note, that’s fine, too. “Relax, free your mind, and your body will do what it's supposed to do,” says Dr. Gupta.