Actually, sex doesn't induce labor, study says

By Kerry Grens, Reuters

NEW YORK - Despite a widespread belief that sex during the later stages of pregnancy can jumpstart labor, a new study from Malaysia found no differences in the timing of delivery between women who had sex near term and those who abstained.

"We are a little disappointed that we did not find an association," said Dr. Tan Peng Chiong, an obstetrics and gynecology professor at the University of Malaya, and one of the authors of the study. "It would have been nice for couples to have something safe, effective and perhaps even fun that they could use themselves to help go into labor a little earlier if (they) wanted."

Tan said that many women believe intercourse can induce labor, and scientists have proposed plausible biological explanations for why it might help.

For one, semen contains a hormonelike substance called prostaglandin, which is used in synthetic form to induce labor.

Breast stimulation is also thought to hasten labor and orgasm can trigger uterine contractions.

Tan said the belief also probably came from "the deep seated folk perception that intercourse in pregnancy may be unsafe and may cause pregnancy expulsion or miscarriage despite fairly replete evidence to the contrary."

But few studies have ever investigated whether sex really can initiate labor, and the small amount of existing evidence was inconclusive, Tan and his colleagues write in the obstetrics and gynecology journal BJOG.

So they set out to see whether advising women to have sex during the final weeks of pregnancy could help them avoid an induction.

"Labor induction for prolonged pregnancy is common and many women are also tempted for a variety of personal reasons to trigger labor off in the very latter stages of pregnancy," he said.

The researchers invited more than 1,100 women to participate, all of whom were 35 to 38 weeks pregnant (the typical pregnancy lasts 40 weeks) and none of whom had had sex in the previous six weeks.

Roughly half of the women were advised by a physician to have sex frequently as a means of safely expediting labor.

The other half were told that sex was safe during pregnancy, but that its effects on labor were unknown.

The researchers then tracked the women to determine how long their pregnancies lasted and whether they required any medical intervention to start labor.

They found that about 85 percent of the women who were encouraged to have sex did follow the doctor's advice, while 80 percent of women in the other group also had sex.

Women in the group advised to have sex also had it more frequently for the remaining duration of their pregnancies - three times versus two.

But the rates of induced labor were similar in both groups: 22 percent of those advised to have sex and 20.8 percent of the other group had inductions, a difference so small it is likely to have been driven by chance.

Pregnancy also lasted an average of 39 weeks for both groups.

Dr. Jonathan Schaffir, an associate professor of obstetrics and gynecology at The Ohio State University College of Medicine who has studied obstetrical folklore, said the findings offer good support for the idea that sex won't induce labor.

Earlier research had relied primarily on surveys of women about their sexual experiences during pregnancy, but this study was "the first attempt to really randomize the experience, for some to have sex and some to not, which is a very hard thing to do," he said.

Schaffir wouldn't advise his patients to have sex for the express purpose of going into labor, he added, but the study did indicate that there aren't any hazards to it.

"Even though this study did not show any increase in the rate of labor or a decrease in the rate of induction, it helped to cement the idea that having sex is probably safe if you want it," he told Reuters Health.

Tan said the results show that pregnancy evolved to be resistant to disruption.

"Human pregnancy has to be robust to a little adventure like intercourse and unfortunately for our purpose, it seems pretty robust to the very end," he said.

Discuss this post

Shhhhh.

  • 4 votes
Reply#1 - Wed Nov 21, 2012 5:37 PM EST

Actually the full title was supposed to be: "Actually, sex doesn't induce labor, study says, IT CAUSES IT"

  • 1 vote
#1.1 - Fri Nov 23, 2012 11:12 AM EST
Reply

That's complete bollocks.............( ;

  • 2 votes
Reply#2 - Wed Nov 21, 2012 6:10 PM EST

But it's still fun trying to prove that study wrong;)

  • 3 votes
Reply#3 - Wed Nov 21, 2012 6:11 PM EST

My husband came back from sea when I was 9 months pregnant and our daughter was born two days later, sex worked for us.

  • 6 votes
Reply#4 - Wed Nov 21, 2012 6:30 PM EST

After intimacy with my husband, I dozed for about an hour. I stood up (to turn over) and my water broke! I was a little over 37 weeks pregnant. Our son was born after many hours of easy labor, an hour+ of absolute HELL, and an emergency C-section.

  • 1 vote
#4.1 - Thu Nov 22, 2012 12:32 AM EST
Reply

I found sex great though,til the BLL stage[baboon like labia]

    Reply#5 - Wed Nov 21, 2012 6:48 PM EST

    It's OBVIOUS that MEN started that rumor in the first place.

    Hey right to lifers, if a fetus is a human being and you have sex with a pregnant woman are you also a pedophile?

    Just asking!

    • 4 votes
    Reply#6 - Wed Nov 21, 2012 7:45 PM EST

    Hey right to lifers, if a fetus is a human being and you have sex with a pregnant woman are you also a pedophile?

    What do you mean *if* a fetus is a human being? What makes you think it isn't? Give me facts.

    Did you see the other article posted next to this one that showed a 4D ultrasound of a baby in the womb yawning? Does that look like inhuman to you for some reason? Do you think there is some sort of alien inside a woman that magically turns into an organism of human species as it passes through the birth canal? Or do you believe that a midwife is responsible for ensuring the magical transformation from non-human to human is successfully completed? Why would a baby on one side of a vagina not be human but on the other side it would be? Are you that much of an idiot or do you have a vivid imagination sufficient for rationalizing an unborn baby isn't human so you can feel good and/or justified when killing it?

    An unborn baby has human DNA. It's also ALIVE; it has a beating heart. If that doesn't make it human by your arbitrary standards then I deem you incapable of having any sort of logical debate with anyone.

    I assume you are one who supports the pro-choice movement. If you are, then why do you feel that the baby shouldn't get a choice about its own life?

    Why is it only the woman who should get to choose? Is it because she is the only one of the two who can vote?

    Why should the baby be punished for the method of conception, something that is out of the baby's control, in the event that a baby is conceived through rape or incest?

    Why treat an unborn baby as property (like we did with slaves a few decades back) that can easily be thrown away whenever a woman feels like it or when we arbitrarily deem it's quality of life to be insufficient to be worthy of being born?

    Who gave anyone of us the authority to say what is a sufficient level of quality for life to exist and if that level isn't satisfied then the authority to extinguish that life (whether at age 100 or an unborn baby or somewhere in between)? Answer: no human has that authority. An abortionist is no different than a gang member gunning down a teenager in cold blood. Neither has the right to take a life, especially that of a CHILD. Children deserve our protection. They are defenseless. It's a sad world when mothers-to-be are killing their own defenseless children before they have a chance to grow up and change the world.

    So, don't worry about being a pedophile when having sex with a pregnant woman but rather worry about being a child murderer if you are pro-choice.

      #6.1 - Thu Nov 22, 2012 11:30 PM EST

      Brandon,

      And for all your rationale, TWO facts remain:

      First, many societies refused to name children before they had been alive for 1-6 months. Other societies, including the Spartans and the Plains Indians (Lakota, et al) insisted on a night of exposure on the infant. And yes, in fact Mosaic law considered both wives and children as chattel, property.

      Second, you like to ignore medical reasons for terminating a pregnancy, and societal reasons. We have learned that certain states routinely aborted young poor women AND nuetered them, so as not to become a burden on the state. Is that any worse than forcing a woman to give birth to an unwanted child, only to find that she will receive NO support or assistance from holy-rollers like you, who are only concerned about the welfare of children, BEFORE they are born?

      And I am a Christian married to a female minister who had two medically required terminations due to a uterus defect (was endangering her life) before we finally had our son, in the fifth year of our marriage.

      • 1 vote
      #6.2 - Fri Nov 23, 2012 12:05 AM EST

      @Brandon,

      It has also been my observation that the most rabid anti-choice folks tend to also be the ones whose solution to every international problem involves dropping bombs on innocent civilians. Reconcile that and you might be worth listening to. Life is either sacred or it is not. Logic is NOT selective.

      I would also remind you that proscriptions against both abortion and birth control are modern inventions. Religion did quite well without them for 3000 years for Jews, 1500 years for Christians and 900 years for Muslims. No sense changing the rules at this late date, is there? Or is it more about men trying to exercise the same controil over women that they had when women were forbidden to vote or own property, for example.

      • 1 vote
      #6.3 - Fri Nov 23, 2012 11:16 AM EST

      It has been my observation that the most rabid anti-choice folks are men.Make that uneducated men who have kids of their own but don't do their share of the child care.

      • 1 vote
      #6.4 - Sat Nov 24, 2012 4:49 AM EST

      Why should the baby be punished for the method of conception, something that is out of the baby's control, in the event that a baby is conceived through rape or incest?

      Brandon, it isn't the baby's fault. But it has to do with compassion. If you had to have a leg amputated, nobody would force you to carry the amputated leg around and care for it on based on an ideology you didn't share. You'd think that was insane, even though that leg was a part of you.

      • 1 vote
      #6.5 - Sat Nov 24, 2012 2:46 PM EST
      Reply

      What idiot ever said that sex DID interfere with labor? Duh. All one has to do is consider that humans have been around and multiplied for millions of years to figure out the facts.

        Reply#7 - Wed Nov 21, 2012 8:46 PM EST

        Another myth busted. Now, both men and women should stop using it as excuse to get what they want.

          Reply#8 - Thu Nov 22, 2012 2:17 PM EST

          Oh I'm sorry I wasn't aware that sex with one's partner was a selfish thing. You don't look like a guy who gets laid very often though.

          • 5 votes
          #8.1 - Fri Nov 23, 2012 8:06 AM EST
          Reply

          No one should be having sex unless they want to BUT it did get my 3 labors started. Two of those were at 37 weeks and one was at 42 weeks. Babies will come when they are meant to come unless something is wrong. Full term is often 42 weeks and sometimes MORE so focusing on 39 week children really shows a lack of knowledge about when babies come and how long gestation is supposed to be. Sex can perhaps help things go more quickly if the woman has a big O bc of the contractions that are part of that function. ;)

          • 1 vote
          Reply#9 - Thu Nov 22, 2012 2:57 PM EST

          If sex did induce labor, husbands would be required to be in the delivery room & in the mother to be.

            Reply#10 - Thu Nov 22, 2012 6:06 PM EST

            This is an incredibly ill-conceived, poorly thought out study. They say: "Women in the group advised to have sex also had it more frequently for the remaining duration of their pregnancies - three times versus two. But the rates of induced labor were similar in both groups: 22 percent of those advised to have sex and 20.8 percent of the other group had inductions, a difference so small it is likely to have been driven by chance." In the first place, sexual activity can only induce labor if (1) the man ejaculates and/or (2) the woman has an orgasm. How many of these sexual encounters included one or both of these experiences? Even more disturbingly ridiculous, why in the world were 21-22% of these women having their labor induced??? Did no one ever hear of simply waiting until the baby is ready to come out? There can't possibly be any medical reason for inducing one fifth of all pregnant women. Just 30 years ago, it was standard practice in the US to allow the mother to go at least 2 weeks beyond her due date, and even then, the advice was to keep physically active to get labor going, not artificial induction. Today, some OBs won't let the woman go even one day beyond the due date before insisting on induction, and many women ask to be induced early for trivial (non-medical) reasons. If you body is 99.9% ready to start labor, an orgasm (or 2 or 3) can certainly kickstart the process by a few hours. But the idea that you could have sex several weeks before your due date and somehow get the baby to come out before it is truly ready is simply untenable.

            • 1 vote
            Reply#11 - Thu Nov 22, 2012 10:10 PM EST

            Kathy Dettwyler,

            Actually, this has a lot to do with scheduling concerns and the convenience of the delivery room and the OB. And unexpected labor, a great number of American women get got short on time to get to the doctor. Imagine a woman in labor riding on the back of a motor scooter, or waiting for the mid-wife traveling by bicycle or motorscooter. You may consider induction some sort of a crime, but it actually makes a lot of sense if you start considering the resource availability and greater danger to mother and child under totally unassisted delivery, where death rates started at 20% for the woman, infant or both in the 1900era in the USA.

            • 1 vote
            #11.1 - Thu Nov 22, 2012 11:49 PM EST
            Reply

            Enormous problem right off the bat- women between 35 and 38 weeks pregnant. Why on earth would the study be performed this way? This is almost a study in reverse, if anything it's showing that sex doesn't cause preterm labor!

            If your body isn't ready to into labor, sex as induction probably won't work (and sometimes pitocin doesn't, either). But if you are 40-42 weeks, it almost assuredly has a much better chance of working. Any midwife knows this. All 3 of my 41-42 week kids were born within 24 hours of a good romp.

            This study is pretty much laughable, I can't even imagine the thought process behind it.

              Reply#12 - Thu Nov 22, 2012 10:15 PM EST

              Emma,

              I can also imagine a hard bowel movement or watching a good comedy show would have the same effect. Look ladies, at 38-42 weeks; typically you're ready to deliver, the baby is ready to be born and ANYTHING will set the process off. Actually, one more-or-less proven trigger is a strong storm. I have had delvery nurses suggest that it has to do with sharp changes in air-pressure. One of the reasons that late term women have trouble trying to fly, as airlines will not take the risks. Btw, cabin pressure in the typical airliner is similar to the average at 10000ft., which takes only two or three minutes to achieve.

                #12.1 - Thu Nov 22, 2012 11:38 PM EST
                Reply

                Tan said the results show that pregnancy evolved to be resistant to disruption.

                What the hell kind of flippant comment is this? There is absolutely no evidence to even suggest pregnancy had to evolve at all. His experiment didn't even focus on that. So why did he feel the need to make a baseless comment like that? Do scientists have some sort of insider quota they abide by that says everything they talk about has to make a reference to evolution no matter how irrelevant it is to the conversation?

                  Reply#13 - Thu Nov 22, 2012 11:13 PM EST

                  Actually I'm pretty sure sex does induce labor, It just takes 9 months.

                  • 4 votes
                  Reply#14 - Fri Nov 23, 2012 12:10 AM EST

                  Pretty much everyone who has gone into labor had sex 1st

                  • 2 votes
                  Reply#15 - Fri Nov 23, 2012 12:15 AM EST

                  A ridiculous research!

                  Or they can layoff all OB-GYN doc. or midwife, and they just bring their sexual partner in hospital for the induced labor; perhaps, they may stay home . . .

                  Oh, they don't need to be under G.A. or E.A. and it will save a lot of money.

                  • 1 vote
                  Reply#16 - Fri Nov 23, 2012 2:05 AM EST

                  Yo Genius:

                  1.)Female orgasms are documented to cause uterine and vaginal contractions.

                  2.)The force of a male partner's penis repeatedly hitting the cervix,which in turn rocks a pregnant uterus back and forth could easily start uterine contractions.

                  3.) Having sex in any position where the non-pregnant partner is pressing even part of their body weight against a pregnant uterus could cause uterine muscles to begin contractions.

                  4.)Either the physical exertion of the sex act or experiencing extremely strong emotions would cause the body to shunt blood away from the uterus to the vital organs,which in turn could potentially cause the uterus to go into muscle contractions.

                    Reply#17 - Fri Nov 23, 2012 5:07 PM EST

                    So that''s how baby's get those soft spots on their heads! I always wondered... ;-)

                      Reply#18 - Sat Nov 24, 2012 7:48 PM EST

                      It does cause what you people call birth marks. When I was inside my Mom, minding my own business. My Dad had sex with my Mom. It's like playing dodge ball during that time. Once afterwards my Mom put her belly beside my Dad. I kicked the you know what at him. (Big mistake on my part.) Dad just turned over and started having sex again with my Mom. I was exhausted from the first dodge ball game. He got me good, and it cause this so call birth mark. Every time my Dad see's my birth mark, he smiles with that grin knowing he caused it.

                      Only on the blog, you learn from us bloggers.

                        Reply#19 - Tue Dec 4, 2012 3:57 PM EST
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