This is a hot topic that I find many of my heavily pregnant patients asking me. Is there some science behind this? Or is it some cheeky myth men perpetuate to get a little more intimacy before the baby comes (and perhaps they won’t have much action for a little while …). As your trusted Pregnancy Chiropractor that loves to go down nerdy research rabbit holes from time to time, I thought I would have a look at the research to see what is out there and share with you my thoughts.
What does the research say about intercourse and the induction of spontaneous labour? What were the conclusions as well as limitations to these studies?
Before I give you some of the findings I want to point out that a topic like this is always going to have limitations and there are so many variables for something so intimate. There is usually a small number of participants and not all of the components of intercourse will be considered as well. For example: did the women have an orgasm during sex? Was there nipple stimulation involved? Were the women involved in the study already past their due date? Therefore more likely to go into labour in the near future. The list goes on! So please don’t take this blog article too seriously and have a little chuckle with me as we weigh up some factors.
Medical interventions and options available aim to mimic physiological changes your body naturally does during birth and postpartum. This will be things to attempt to induce labour, soften and ripen your cervix and get your body ready to birth. This includes prostaglandins levels and exposure, hormones the body releases to get the cervix to ripen but also things that happen after the birth of your baby to encourage uterus contractions.
Factors to consider when it comes to elements of sex and the induction of labour:
Prostaglandins are a big consideration when it comes to the induction of labour. Prostaglandins, which are naturally produced in the cervix and uterus, serve as mediators of cervical ripening (5).There are also prostaglandins in seminal fluid. It is there to help with sperm motility and transport. Prostaglandins are definitely a factor for induction as there is also a prostaglandin gel that can be offered to you when trying to induce labour. However, keep in mind that your partner won’t necessarily have a high amount or higher amount of prostaglandins compared to the pharmacological types which are synthetic. This is one of the main theories to give it a go to see what happens.
Human semen is the biological source that is presumed to contain the highest prostaglandin concentration. I would assume that this is the foundation as to why sex has been encouraged to potentially induce labour.
Oxytocin- the “love hormone” is a key player around labour and birth. There is a synthetic version that is the most commonly used drug to bring on labour as well. Natural oxytocin can also be released naturally through hugging and sex. This could also be why you may see some “Hypnobirthing” mums being held by and hugging their partner during components of labour. The hormones our body releases during and after an orgasm are also the same hormones that are released during labour, birth and postpartum bonding. So hey! If your partner wants to make it worth your time then make sure it is satisfying for you!
Nipple stimulation can play a part when preparing your body for birth. When a baby attaches to the breast, the nipple stimulation will tell your brain that you have birthed your baby and will need to feed them. Your brain will then get your uterus to contract (which is why it’s handy for labour) to bring the uterus back to pre-pregnancy size. Another factor to consider is antenatal expressing as another recommendation to attempt in the lead up to your due to to help prepare your body. It can also increase hormones that can be useful for labour. If nipple stimulation is something that you engage in during sex… this could also be for you.
What some research has found:
I had a little dig around some research and I will highlight some key points.
One paper (1) found that pregnant ladies that were sexually active in their pregnancy had younger gestational ages on average. Meaning that babies were more likely to go past their due date for mums that were less sexually active.
One randomised control trial (2) did not find that sex could speed up spontaneous labour - sorry partners!
A paper (3) that looked at multiple randomised control trials made some great points. This paper highlighted the need for further evaluation of the impact of orgasm, penetration, condom use, frequency of intercourse and other factors on induction of labor at term.
So there we have it! A few little things to consider but ultimately you should do what feels right to you- no matter what. There could be other reasons as to why your baby has not entered the world just yet such as head engagement and if there is enough space in the pelvis that they can pass through to come earth-side! If you want to make sure your body is moving quite well to assist in your birthing outcomes, please feel free to book an appointment here.
1. Kafaei Atrian M, Sadat Z, Rasolzadeh Bidgoly M, Abbaszadeh F, Asghari Jafarabadi M. The association of sexual intercourse during pregnancy with labor onset. Iran Red Crescent Med J. 2014 Dec 26;17(1):e16465. doi: 10.5812/ircmj.16465. PMID: 25763253; PMCID: PMC4341500.
2. Castro C, Afonso M, Carvalho R, Clode N, Graça LM. Effect of vaginal intercourse on spontaneous labor at term: a randomized controlled trial. Arch Gynecol Obstet. 2014 Dec;290(6):1121-5. doi: 10.1007/s00404-014-3343-0. Epub 2014 Jul 18. PMID: 25033717.
3. Carbone L, De Vivo V, Saccone G, D'Antonio F, Mercorio A, Raffone A, Arduino B, D'Alessandro P, Sarno L, Conforti A, Maruotti GM, Alviggi C, Zullo F. Sexual Intercourse for Induction of Spontaneous Onset of Labor: A Systematic Review and Meta-Analysis of Randomized Controlled Trials. J Sex Med. 2019 Nov;16(11):1787-1795. doi: 10.1016/j.jsxm.2019.08.002. Epub 2019 Sep 11. PMID: 31521572.
4. Kavanagh J, Kelly AJ, Thomas J. Sexual intercourse for cervical ripening and induction of labour. Cochrane Database Syst Rev. 2001;2001(2):CD003093. doi: 10.1002/14651858.CD003093. PMID: 11406072; PMCID: PMC7017007.
5. Pierce S, Bakker R, Myers DA, Edwards RK. Clinical Insights for Cervical Ripening and Labor Induction Using Prostaglandins. AJP Rep. 2018;8(4):e307-e314. doi:10.1055/s-0038-1675351