Is sex safe during pregnancy?

The verdict

Yes. The NHS states it directly: it is safe to have sex when you are pregnant unless your doctor or midwife has told you not to, your baby is safe in your womb, and having sex will not hurt them.

ACOG says the same thing and explains why. Most sexual activity is safe in a healthy pregnancy, including intercourse or penetration with fingers or sex toys, because the amniotic sac and the strong muscles of the uterus protect the fetus.

There is no trimester in which sex is off limits, no frequency limit, and no position that has been identified as unsafe. The exceptions are specific, few, and something your midwife would have told you about.

The exceptions, named

The NHS lists the circumstances in which you may be advised to avoid penetrative sex, meaning a penis or sex toy going inside the vagina:

• A low-lying placenta or placenta praevia, because there is a risk of bleeding.
• Your waters have broken, because there is an increased risk of infection.
• You have had several miscarriages.

Placenta praevia is the one most people will not know about without a scan. The RCOG's patient information explains that it means the placenta lies low in the uterus and partly or completely covers the cervix, which is exactly the tissue that penetration disturbs. It is picked up at the mid-pregnancy scan, and if you have it you will have been told.

The NHS adds a fourth, situational rule: bleeding in pregnancy is quite common and may not mean there is a problem, but it is always best to get it checked, and it is a good idea not to have sex until you have been checked. That is not a permanent restriction; it is a pause pending assessment.

Oral sex, sex toys and orgasm

The NHS treats each of these separately, which is useful because the answers are not identical.

Oral sex is safe in pregnancy unless you or your partner have cold sores, because cold sores are caused by the same virus as genital herpes, which could be passed to your baby and make them very ill. That is a genuine and specific caution.

Sex toys are safe unless you have been advised otherwise, with the practical addition that they should be kept clean, washed after each use if shared, and given a new condom each time. The NHS also suggests that if you have been told to avoid sex, you ask whether that includes sex toys, because people often assume it does not.

On orgasm the NHS is candid about the evidence: there is little research on the effects of orgasm in pregnancy, but it is thought to be safe. It notes that in later pregnancy, sex or orgasm may cause Braxton Hicks contractions, when the muscles of your womb go hard. This is normal and is not the start of labour.

Infection is the part worth taking seriously

The NHS is firmer about sexually transmitted infections than about anything else on this subject. If you have symptoms of an STI, or think you or your partner may have one, use a condom for sex including oral sex, and go to a sexual health clinic to be checked, because an untreated STI could cause serious harm to you and your baby. If you or your partner have sex with other people during the pregnancy, barrier contraception is important for the same reason.

It also flags bacterial vaginosis, which is not an STI but is caused by a change in the natural balance of bacteria in the vagina and can be triggered by any sort of sexual activity. It does not cause problems in most pregnancies, but there is a small chance of complications such as premature birth and miscarriage, and it is treatable with antibiotics. Unusual discharge is worth mentioning to your midwife rather than waiting to see.

What changes, and what that is not

Desire commonly changes in pregnancy, in both directions and often more than once. The NHS lists the reasons without moralising about them: changes in your body and how you feel about it, pregnancy hormones, worries about the pregnancy or about whether sex is safe, and sickness and other symptoms. Many people find they have less sex as pregnancy progresses. All of that is normal.

Physical comfort changes too. Tender breasts make partner-on-top uncomfortable early on, and the bump makes it impractical later. The NHS suggests trying side-by-side positions, and notes that hormonal changes can leave the vagina drier, so a water-based lubricant may help.

Partners often worry that penetrative sex will hurt you or the baby, and the NHS addresses this explicitly: this is not unusual, and it is worth talking about rather than assuming. Kissing, mutual masturbation and massage are named as alternatives if penetrative sex is not wanted or not advised.

Sex does not start labour

This is the most persistent piece of folklore in late pregnancy, and the NHS now answers it flatly: there is no evidence that having sex will help start labour, and some research has shown that it does not. If your waters have broken, avoid sex because of the infection risk. Otherwise, at 40 weeks, sex is neither a treatment nor a hazard.

Where guidance differs

It essentially does not, which is worth stating because this is a question people ask nervously.

The NHS and ACOG give the same verdict and nearly the same reasoning. The NHS is the more detailed of the two, working through oral sex, sex toys, orgasm, positions, libido and the effect on partners, and naming its exceptions explicitly. ACOG's answer is shorter and leads with the anatomy: the amniotic sac and the uterine muscle protect the fetus, and anyone with pregnancy complications or questions should ask their ob-gyn.

Neither publishes a gestational cut-off. Neither restricts frequency. Neither recommends condoms for a monogamous couple without an infection concern. And neither treats a first-trimester history of miscarriage in general as a reason to abstain, although the NHS does name recurrent miscarriage as a situation in which you may be advised to avoid penetrative sex.

If you have been told to avoid sex, the useful question to ask is what exactly is included, because the answer varies by reason. Avoiding penetration because of placenta praevia is not the same instruction as avoiding sex entirely after your waters have broken.