How Does Sex Induce Labor? When To Have It, Best Positions, & More

From old standbys like eating spicy foods to the awkward balancing act that is curb walking, there are a plenty of things that pregnant people try when they’re ready to induce labor naturally. One of the most tried and true DIY ways to kickstart your baby’s birth, though, is to head to the bedroom. (Or the couch, kitchen table, floor, etc. After months of pregnancy, you’re not picky.) But exactly how does sex induce labor? There are a few details to note if you’re ready to try this route. From when to have sex to induce labor, the best positions to attempt, and more, here’s what you need to know.

Does sex induce labor?

Having sex is known as a way to induce labor. Though there is little clinical research available to back up the science of how it all works, anecdotally, the act is known to kickstart the labor process. However, it is not advised by most providers to try this tactic until after a pregnancy reaches full term, or 37 weeks gestation, according to board-certified obstetrician Dr. Cynthia Flynn. You should also get an OK from your healthcare provider before trying this or any other natural induction method.

“You should not have sex if you have a complicated pregnancy or your doctor has asked you to abstain,” says Flynn. That said, unless you have a contraindication such as a cervical insufficiency, an overactive cervix or friable cervix, overactive uterus, a ruptured amniotic sac, or other diagnosed medical issue, having sex to stimulate labor is perfectly safe and can be effective.

How does sex induce labor?

Sex can help to induce labor in two ways — chemical and physical — according to birth educator and doula Sara Lyon.

Ejaculation during penetrative sex provides the first type of chemical reaction that can help induce labor. “Chemically, semen contains the hormone prostaglandin, and prostaglandin can stimulate dilation of the cervix when applied locally,” Lyon says. Yes, sperm can soften the cervix and induce labor, but so can the hormones released during orgasm. “Additionally, the hormone oxytocin rises with intimacy, especially with orgasm, and oxytocin inspires contractions in the uterus and dilation in the cervix.”

Reaching orgasm during sex can also play a role in the physical process of stimulating labor, according to both Flynn and Lyon. As the pelvic muscles and cervix contract and relax during orgasm, these actions can induce uterine contractions to jumpstart labor. “Vaginal penetration and contact with the cervix can activate contractions as well,” Lyon says.

How much sex do you have to have to induce labor?

There is no specific data available to explain exactly how much sex is enough sex to induce labor. In short, it’s different for everyone. The length of time that sex lasts and the frequency of the act don’t necessarily impact whether or not having sex will actually lead to labor, according to both Flynn and Lyon. What really matters is reaching orgasm.

When should you have sex to induce labor?

Having sex during pregnancy is safe for most pregnant people unless otherwise indicated by their provider, but the ideal timing of sex to induce labor is once the pregnancy has reached full-term, or at least 37 weeks gestation.

“Unless you have a contraindication, sex during pregnancy is very unlikely to start labor before your due window,” Lyon says. Your due window describes the time period two weeks before and two weeks after your estimated due date. “If you’re really trying to start labor, focus on the last two weeks before your estimated due date,” Lyon tells Romper.

What are the best sex positions to induce labor?

The best sex positions to induce labor are the ones that help you reach orgasm. You know your body best. Whatever position feels most comfortable for your pregnant body and helps you achieve climax is the route to take. This can even include oral sex, digital penetration, or masturbation.

In short, “just make it as pleasurable as possible,” Lyon says. Also, keep in mind that “more orgasm = more oxytocin = more contractions. Whether that’s enough to catalyze labor is dependent on the individual body,” she explains.

Though there are no specific sex positions guaranteed to induce labor, some of the best positions for expectant parents to try include those that allow control over depth of penetration and pacing like cowgirl, reverse cowgirl, spooning, and doggy style.

What about positions to avoid? It’s important to note that with labor around the corner, any sex positions that get too rough might not be great comfort-wise or for inducing labor. “You don’t want to bruise or inflame the cervix because that could interfere with dilation, so don’t go wild with deep, forceful penetration because the cervix will already be dropped lower into the vagina at the end of pregnancy,” Lyon says.

As with anything pregnancy related, your provider is your best resource for questions regarding what is safe for you, including sex to induce labor.

In the end, sex to induce labor could work, but it might not. There’s no magic or instant solution. Your baby will be here when your baby is ready (and your body, too). But if you’re in the mood and it’s safe for you to do so, sex to induce labor could be worth a try.

Sources interviewed:

Sara Lyon, birthing expert, doula and author of You’ve Got This: Your Guide to Getting Comfortable with Labor

Dr. Cynthia Flynn, board-certified OB-GYN with JustAnswer, practicing in Florida