How Does Childbirth Affect the Pelvic Floor?

A vaginal birth asks the muscles at the bottom of your pelvis to open wide enough for a baby’s head, then close back up and go straight back to work holding in pee, poop, gas, and your pelvic organs. Usually they manage. Sometimes a muscle gets pulled past its limit, a nerve gets bruised, or the skin and muscle near the vagina tear, and the effects show up the same week, a few months later, or decades down the road.

And the timeline runs a lot longer than the six-week checkup makes it sound.

What gets stretched during a vaginal birth?

Three kinds of tissue take the hit. Muscles, the nerves that run them, and the connective tissue that helps hold your bladder, uterus, and rectum in place.

Start with the muscles. The main group, the levator ani, is a sling of muscle across the base of your pelvis. A 2024 editorial in Acta Obstetricia et Gynecologica Scandinavica, summarizing earlier research, notes that its innermost fibers can stretch to 2.5 times their original length during birth without rupturing. Think hair tie over a coffee mug.

Sometimes the muscle doesn’t stretch far enough and pulls away from its attachment on the pubic bone instead. That’s a levator avulsion. A 2024 meta-analysis of 25 studies, covering more than 9,300 women after their first vaginal birth, found major avulsion in an average of 22 percent of them. It’s diagnosed on ultrasound or MRI, so you may not know you have one.

The nerves are the second piece. A 1990 study¹ in the British Journal of Obstetrics and Gynaecology tested 96 women having their first baby, and 80 percent of those who delivered vaginally showed signs of nerve regrowth afterward. Regrowth means something got damaged first… The longest pushing stages and the heaviest babies went with the most nerve damage. Forceps and tears, oddly, didn’t change how much the researchers found. For most women the damage was partial and the nerves reconnected, but in a few it came with urinary and fecal incontinence.

Tears, stitches, and the perineum

The perineum, the stretch of skin and muscle between the vagina and the anus, takes the most visible damage. Up to 90 percent of women who give birth vaginally have some tearing, according to Cleveland Clinic².

Second-degree tears are the most common. That means skin plus the muscle underneath, closed with stitches. Cleveland Clinic² says those stitches dissolve on their own, and most women feel relief from the pain in about two weeks.

Third- and fourth-degree tears go further. They reach the anal sphincter, the muscle that controls the anus, and a fourth-degree tear extends into the rectum. About 5 percent of women who give birth vaginally have one, per Cleveland Clinic², which lists leaking stool and painful sex among the possible complications.

If you had a third- or fourth-degree tear, ask before you leave the hospital who will follow up with you, and when.

Why forceps keep coming up

Forceps show up in this research like a recurring character. In that 2024 meta-analysis, forceps births carried about six times the odds of a major avulsion. Vacuum births carried about 2.4 times the odds, and a third- or fourth-degree tear nearly four times.

Why care about an avulsion you can’t see? Because it tends to cause trouble later. The Acta editorial reports that women with an avulsion had twice the risk of prolapse symptoms and four times the risk of prolapse found on a pelvic exam. Prolapse is when the bladder, uterus, or rectum drops and presses into the vagina, and it has its own article here.

The calls in a delivery room get made fast, by people reading a monitor while you were busy pushing. Teams usually reach for forceps or a vacuum when getting the baby out quickly is the safest option for you or your baby. What you can do now is keep a record. Forceps, a long push, a big baby, a bad tear. Write those details down while you still remember them, because they change what’s worth watching for.

Does a C-section protect the pelvic floor?

Partly. Not completely.

An NIH-funded study led by researchers at Johns Hopkins Bayview, published in JAMA in 2018, enrolled more than 1,500 women 5 to 10 years after their first delivery and followed them for up to nine more years. Compared with a spontaneous vaginal birth, a cesarean came with about half the risk of stress incontinence and overactive bladder, and about a 70 percent lower risk of prolapse. A forceps or vacuum birth meant nearly twice the risk of anal incontinence and prolapse, compared with a spontaneous one. The Acta editorial adds that levator avulsion isn’t seen after cesarean.

But the NICHD³ says a cesarean reduces the risk of pelvic floor problems without eliminating it. Women who have never been pregnant get these problems too. And pregnancy itself plays a part, which we cover in our article on how pregnancy affects bladder control.

A C-section is also abdominal surgery, with risks of its own. The NHS⁴ lists wound infection and blood clots among them, and, less commonly, trouble with the scar or the placenta in a later pregnancy. If you’re weighing a C-section for a future birth, the pelvic floor is one item on a longer list to talk through with your clinician.

How long does recovery take?

Longer than six weeks. Months longer, for plenty of women.

A 2022 study⁵ in the International Urogynecology Journal followed 235 first-time mothers in Norway from mid-pregnancy to a year after birth. The same research team had earlier found that six weeks after a normal vaginal birth, pelvic floor muscle strength averaged 54 percent below the mid-pregnancy level, and endurance 53 percent below. A year after a normal vaginal birth, most of that had come back in the 2022 group, on average, though women varied. Strength sat 7.5 percent below the pregnancy measurement. Endurance had climbed 9 percent above it. After forceps or vacuum, strength was 15 percent short at a year. Women who had a cesarean ended the year stronger than in pregnancy, and the authors called cesarean protective.

So the strength comes back. Slowly, though, and slower for some women than others. Higher BMI, a longer pushing stage, and a major levator tear all dragged on recovery, the levator tear most of all. The authors concluded that more physical therapy follow-up may be warranted after birth, especially after a complicated vaginal delivery.

We agree with them. One checkup at six weeks, when strength after a vaginal birth averaged about half its pregnancy level in the team’s earlier research, shouldn’t be the last time anyone asks about your pelvic floor. If the six-week check came and went without a question about leaking, heaviness, or sex, bring it up yourself at your next appointment, or ask whether a referral to a pelvic floor physical therapist makes sense for you. Check with your clinician before starting pelvic floor exercises or getting back to running and lifting, especially after a bad tear or a C-section.

What it can feel like, now and years from now

Leaking pee when you cough, laugh, or lift is the symptom people talk about most, and we cover it separately. It isn’t the only one. The NICHD³ also lists trouble controlling gas or stool, a bulge in the vagina, and a heaviness, fullness, pulling, or aching there that gets worse by the end of the day. Picture an ache that’s barely there at breakfast and has your full attention by the time you’ve been on your feet with a baby on your hip all afternoon.

Some of this waits years. In the JAMA study, the chance of stress incontinence starting was highest in the first five years after delivery. For prolapse, the researchers estimated the peak comes more than 20 years out.

When to get checked

Don’t wait if

1. Emergency

   Urgent warning signs can come on during pregnancy and for a full year after delivery, the CDC⁶ says, and its full list covers far more than the pelvic floor. Call 911 or your local emergency number, or go to the ER, for any of these.

2. Emergency

   If you have thoughts of harming yourself or your baby, call 911 or call or text 988, the Suicide & Crisis Lifeline in the US, now.

3. Urgent

   Get medical care right away for a temperature of 100.4°F (38°C) or higher, a headache that won’t go away, changes in your vision, or vaginal discharge that smells bad. That means calling your doctor or midwife, and going to urgent care or the ER if you can’t reach them.

• Bleeding that soaks through one or more pads in an hour
• Passing clots bigger than an egg, or passing tissue
• Chest pain or trouble breathing
• Swelling, pain, or tenderness in one leg, usually the calf

Call your doctor, midwife, or nurse promptly for these. The first four come from Cleveland Clinic’s² list for after a tear.

• Stitches that get more painful
• Pain that keeps getting worse even with pain medication
• Losing control of your bowels
• Pain when you pee
• Not being able to pee, or only managing a dribble, in the hours or days after birth

That last one can be a sign of urinary retention. Cambridge University Hospitals NHS Foundation Trust⁷ says the urge to pee should return within about four hours of the birth or of a catheter coming out, and that untreated retention can cause pain, long-term bladder damage, and incontinence.

And make an appointment, without waiting for things to sort themselves out, if you notice a bulge, heaviness that builds through the day, leaking that’s still going past six weeks, trouble holding in gas, or pain with sex once you’ve been cleared for it.

The twelve-month recovery numbers above came from 235 women in Norway, averaged together. Yours doesn’t have to run its course before you ask for help.