Lucy Flynn, BABYGO® team
Somewhere around 20 weeks the bump starts getting in the way, and the way you've always done things needs a rethink. Or you're earlier than that, and the question isn't how but whether it's safe at all.
Both are normal, and both have plain answers. Sex in a normal pregnancy is safe from start to finish; what changes is which positions are comfortable. Here's what works in each trimester, what to do about the bump, and the few situations where the NHS says stop and ask.
Quick answer: In an uncomplicated pregnancy, unless your midwife or doctor has told you otherwise, sex is safe up to the end and no position harms the baby. What changes is comfort: anything with weight on your bump, or with you flat on your back, gets harder from about 20 weeks, so you move to side-lying, you on top, or from behind. Stop and ring your midwife if you bleed, your waters go, or you've been told to avoid it.
The facts underneath all of this:
- The NHS says it's perfectly safe to have sex in pregnancy unless your doctor or midwife has told you not to, and it won't hurt your baby: your partner's penis can't go beyond your vagina.
- You may be told to avoid sex after heavy bleeding, if your waters have broken, if there's a problem with your cervix, or later in pregnancy if you're carrying twins or have had early labours before.
- Changes to the blood vessels in your cervix can cause bleeding after sex. The NHS says get any bleeding checked.
- After 28 weeks the NHS advises going to sleep on your side, which is also why side-lying positions come into their own in the third trimester.
- Seven positions below. None is banned by trimester; three get awkward once the bump is big.
Is it safe to have sex while pregnant?
Yes, in a normal pregnancy. That's the NHS position in as many words: perfectly safe unless your doctor or midwife has told you not to. Having sex will not hurt your baby. Your partner's penis can't penetrate beyond your vagina, and the baby, as the NHS puts it, cannot tell what's going on.
Partners worry about this one more than you'd expect, so it's worth saying out loud: they can't reach the baby and they can't hurt the baby. If either of you still feels odd about it, that's allowed too. Sex isn't only penetration, and a pregnancy where you'd rather cuddle for three months is not a problem.
A bit of spotting afterwards can happen. The blood vessels in your cervix change in pregnancy, and the NHS lists that as a cause of bleeding after sex. It can be nothing. You still get it checked, every time.
When to stop sex during pregnancy
Most people never need to. The NHS lists a short set of situations where you'll probably be advised to avoid it:
- you've had any heavy bleeding in this pregnancy
- your waters have broken, because sex can increase the risk of infection
- there's a problem with the entrance to your womb, the cervix
- you're carrying twins, or you've had early labours before, and you're in the later stages of pregnancy
A low-lying placenta, or placenta praevia, is the other big one. RCOG's leaflet notes that bleeding from placenta praevia is usually painless and may come on after sex, so if your 20-week scan found a low placenta, ask your midwife what applies to you.
If you've been told to avoid sex, ask whether that includes sex toys and orgasm, so you're not guessing.
| What's happened | What to do |
|---|---|
| Light spotting after sex, no pain | Call your maternity unit. Under 20 weeks, an early pregnancy unit may be able to help; if you can't reach either, call NHS 111. Hold off on sex until you've been checked. |
| Bleeding with pain in your tummy or shoulder, feeling faint or sick, or heavy bleeding | Call 999. The NHS bleeding page is clear on this one. |
| Your waters have broken | Call your midwife. Pad, not tampon, so they can check the colour (NHS). No sex, because of the infection risk. |
| You've been told to avoid sex | Ask exactly what it covers, for how long, and whether it includes orgasm and sex toys. |
Want this by trimester, for your dates? Tell us your due date and we'll send what to expect each week, comfort included. 10% off when you're ready.
Pregnancy sex positions by trimester
Here's the whole thing on one screen. The weeks are rough; go by how you feel, not the calendar.
| Position | First trimester (to 12 weeks) | Second (13 to 27) | Third (28 to 40) | Watch for |
|---|---|---|---|---|
| Classic missionary | Fine | Fine until about 20 weeks, then your partner's weight and lying flat both start to bother you | Skip it, or keep it to a few minutes propped up | Dizziness on your back; weight on the bump |
| Modified missionary (partner kneeling, no weight on you) | Fine | Good | Good, with pillows under your back and shoulders | Prop yourself up if lying flat makes you dizzy |
| Spooning | Fine | Good | The winner | Shallower; your partner's hands are free |
| Cowgirl (you on top) | Good | Good | Good; kneel rather than squat | You set the depth and pace; kind to sore hips |
| Doggy style (hands and knees) | Fine | Good | Good; takes the pressure off your back and pelvis | Deeper; your wrists if you've got carpal tunnel |
| Scissors | Good | Good until the bump is in the way | Awkward | Shallow; face to face |
| Side saddle | Good | Good | Possible, propped up and tilted to your left | Your partner does the work |
First trimester (weeks 1 to 12)
Nothing is off the table. There's no bump yet, so the usual positions are all fine, missionary included. What gets in the way in the first twelve weeks is how you feel: the tiredness, the nausea, the boobs that don't want touching.
So the best position now is whichever one asks the least of you. Missionary and side saddle let your partner do the work; scissors is close and slow if you're feeling fragile about a body that's changing.
If you had bleeding early on, or you're waiting on a scan, holding off until you've been seen is completely reasonable. Ask at the appointment.
Second trimester (weeks 13 to 27)
For a lot of people this is the good bit: the sickness has eased, the energy's back, and the bump is there without being enormous. The answer is the same from the fourth month to the sixth. Most positions still work, with one shift somewhere around 20 weeks.
That shift is lying flat on your back. From about 20 weeks the weight of the womb sits on the big blood vessels behind it, and some people feel dizzy or breathless lying flat for long. Dizziness is your cue to move: prop yourself up, tilt onto your left side, or swap to you on top, side saddle or modified missionary, where nobody's weight is on the bump.
Third trimester (weeks 28 to 40)
Now the bump runs things. The positions that keep working are the ones where it's out of the way: spooning, hands and knees, and you on top, kneeling rather than squatting.
Pillows everywhere. Under the bump on your side, under your hips or chest on all fours, behind your back if you're propped.
The NHS advises going to sleep on your side from 28 weeks. That's about sleep rather than sex, but it's the same logic: don't spend long flat on your back this late. If your pelvis has started hurting (pelvic girdle pain, or SPD), spooning keeps your knees together and is usually the kindest; there's more in our pelvic girdle pain piece.
And if you're wondering whether sex in the last few weeks will start labour: in a normal pregnancy, "near your due date" isn't on the NHS list of reasons to stop. If you've been told you're at risk of an early labour, that's different, and it's on the list above.
Which sex position is safest during pregnancy?
In an uncomplicated pregnancy none of them is unsafe for the baby, so "safest" really means most comfortable and most in your control. That's you on top: you set the depth and the pace, and nothing presses on the bump. The only rule is no weight on the bump and no long stretches flat on your back late on.
The positions, one by one
Classic missionary
Fine in the early months, as long as your partner takes their weight on their arms and you don't stay flat for long; there's no set number of minutes, but feeling dizzy or sick means move. It's face to face, and your partner does the work when you're tired. By the second half of pregnancy it's hard to manage without weight on the bump, and most people drop it.
Modified missionary
Same idea, but your partner kneels and stays upright, so there's no weight on your belly and you can use your legs to draw them in and set the pace. Works the whole way through; prop your shoulders up if lying flat makes you dizzy.
Spooning
Both on your sides, your partner behind you. This is the one for when you want to, but the bump and the tiredness are making everything else a bit much. Good at any stage and usually the best of the lot in the third trimester. Penetration is shallower, and your partner's hands are free.
Cowgirl
You on top, facing your partner. You control depth and speed, nothing presses on the bump, and because your legs don't need to be wide it's kinder on sore hips. Kneel rather than squat in the third trimester. Plenty of people feel bolder in pregnancy, and this is the position for that.
Doggy style
On your hands and knees, your partner behind. Works at any stage and comes into its own late on, because your belly hangs free and the pressure comes off your back and pelvis. Penetration is deeper, so say if it's too much. If your wrists hurt (carpal tunnel), rest on your forearms, or kneel at the edge of the bed with your partner standing.
Scissors
Lying face to face, legs interlocked. Close, slow, nothing on the bump. Good in the first trimester and most of the second, while there's room, and a gentle option if you're nervous early on. Penetration is shallow, so it isn't everyone's favourite.
Side saddle
You on your back or propped up, your partner sitting or kneeling across your legs. They do all the work, which is what you want when you're wiped out. Good through the first two trimesters; possible in the third if you're propped up and tilted to your left rather than flat.
A pillow under the bump makes half of these easier
You don't need anything to have sex in pregnancy. But a full-length pregnancy pillow is what turns "on your side" from a compromise into a position you can relax in, because it holds the bump and the top knee so your pelvis isn't twisting, and it's what you'll be sleeping on from 28 weeks anyway. Back, hips and sleep are the words that come up again and again in the reviews.
BABYGO® Moon Pregnancy Pillow
Full-length support for the bump, back and knees when you're on your side; fold the bottom under if you're shorter. One size, with a washable bamboo and cotton cover. One reviewer wrote: "The cover feels soft and the curved shape works well for side sleeping."
Questions we get asked
Is missionary safe during pregnancy?
Safe for the baby, yes, at any stage. The issue is comfort: your partner's weight and you lying flat. Fine early on; from about 20 weeks keep it short and propped up, and by the third trimester most people switch to the kneeling version or something side-on.
Which sex positions should you avoid in pregnancy?
None are banned. Past about 20 weeks, avoid weight on your bump and long stretches flat on your back.
What's the best sex position in the 9th month of pregnancy?
Spooning, for most people. The bed takes the bump, your partner's weight is nowhere near it, and you can stop and start without a production. Hands and knees still works at 36 weeks plus, especially with an aching back, and kneeling on top does if you've got the energy. Have pillows within reach.
Can sex bring on early labour?
In a normal pregnancy it isn't on the NHS list of reasons to avoid sex. Where it comes up is if you've had early labours before or you're carrying twins, when you may be advised to avoid sex in the later stages. If that's you, your midwife will have said so.
Is it normal to bleed after sex when pregnant?
It happens, because the blood vessels in your cervix change in pregnancy; the NHS lists it as one cause of bleeding after sex. It still gets checked: your maternity unit, an early pregnancy unit if you're under 20 weeks, and 999 if it's heavy or comes with pain or feeling faint.
How long should you stop having sex during pregnancy?
Only as long as your midwife or doctor says, and in a normal pregnancy that's not at all. If you were told to stop after a bleed, ask when it's fine to start again.
If side-lying is where you've landed, the pregnancy pillows are here, and if it's your pelvis rather than the bump that's the problem, start with the pelvic girdle pain piece.
This is general guidance from the BABYGO® team, not medical advice. Your midwife or GP knows your pregnancy; ask them if anything here doesn't fit your situation.
