I was 38 weeks and 4 days. I had just sat down on the sofa with a cup of tea and a wave of warm water hit the cushion beneath me. Not a gush. Not the dramatic film version. A trickle that did not stop. I knew immediately, even though I had told myself for weeks that I would not know.
What I did not know was what to do next. I was not in labor. I had no contractions. The hospital triage line answered in 90 seconds and asked the same three questions every hospital asks: when, what color, are the baby's movements normal. Then they said the sentence that nobody had prepared me for: "Come in for an assessment and then we will probably send you home and ask you to come back in 24 hours if labor has not started."
If your waters have broken but contractions have not started, you are now in a specific medical category called pre-labor rupture of membranes (PROM), where the amniotic sac has broken before labor has begun. Here is the real timeline, the infection risk at each window, and the conversation worth having with your midwife before you make the next call.
What is actually happening
The amniotic sac (the bag of fluid surrounding the baby) ruptures, releasing the warm liquid that has cushioned your baby for nine months. In most cases this happens during labor, after contractions have started. In about 8 to 10 percent of pregnancies at term it happens before labor. That is PROM.
Once the sac has broken, the protective barrier between the inside of the uterus and the outside world is gone. Bacteria from the vagina can travel up. The longer the gap between waters breaking and birth, the higher the infection risk for both you and the baby. This is why every hospital has a clock running from the moment your waters break.
The real timeline and induction window
The current guidance from the American College of Obstetricians and Gynecologists, NICE in the UK, and most maternity systems globally is the same:
- Within 24 hours of waters breaking, around 80 to 90 percent of women will start labor spontaneously
- Beyond 24 hours, the risk of infection in mom and baby rises noticeably
- Most hospitals recommend induction at 24 hours after PROM if labor has not started on its own
Some hospitals offer immediate induction at the point of confirmed PROM. Others offer 12 to 24 hours of expectant management (waiting at home or in hospital, monitored, to see if labor starts). Both are evidence-supported. The choice often comes down to your hospital's policy and your own preference.
Infection risk at each hour mark
The numbers worth knowing, based on current evidence:
- At time of rupture: baseline infection risk in babies of moms whose waters have NOT broken is roughly 1 in 200
- Within 24 hours of broken waters: risk is roughly 1 in 100, twice the baseline
- At 48 hours: risk is roughly 2 in 100
- At 72 hours: risk is roughly 4 in 100
These numbers are still low in absolute terms. But they double every 24 hours, which is why the timeline matters.
The bigger risk is to the baby. Newborn infections from prolonged PROM can be serious, ranging from mild jaundice to neonatal sepsis (a bloodstream infection in newborns) which can need NICU care. (We covered some of the signs to watch for in [Newborn Jaundice: What Is Normal and When to Call Your GP](/blog/newborn-jaundice-when-to-call-gp).)
What to do when your waters break
The first 30 minutes after you realize your waters have broken matter for the rest of the timeline.
1. Check the color
Amniotic fluid is normally clear, straw-colored, or slightly pink. Note the color on the pad or your underwear.
Call the hospital immediately if:
- The fluid is green, brown, or dark (this can mean the baby has had a bowel movement, called meconium, which can cause breathing problems if inhaled)
- The fluid is bright red or mixed with significant blood
- You cannot feel the baby moving as normally as you would expect
- You feel ill, feverish, or have any new pain
These are the only situations where you must go in straight away regardless of contractions.
2. Note the time
Write it down. The clock is going to be the single most important number in every conversation with the hospital for the next 48 hours. Hour zero is when your waters broke, not when you noticed.
3. Use a maternity pad, not a tampon
Tampons after PROM are completely off the table. They introduce bacteria. A standard maternity pad lets you see the color and amount of fluid coming through.
4. Call the hospital triage number
Every maternity unit has a 24-hour line for this exact call. They will ask:
- When did it happen?
- What color and how much fluid?
- Is the baby moving as usual?
- Are you having any contractions yet?
- Have you had GBS (Group B Streptococcus, a common bacteria some women carry that needs IV antibiotics during labor) confirmed?
Based on the answers, they will either ask you to come in for an assessment or to monitor at home and call back if anything changes.
What expectant management looks like
If you are sent home after the assessment (which is common at term with clear fluid and normal movements), expectant management means watching the clock and your body. The standard advice:
- Take your temperature every 4 hours. Anything 37.5 degrees C / 99.5 F or above is a reason to call back. Fever is the earliest sign of infection.
- Avoid baths and sex. Both increase the risk of bacteria reaching the uterus. Showers are fine.
- Watch movements. The baby should be moving as much as before, not less.
- Note the fluid color. If it becomes green, brown, or smelly, call back.
- Eat a normal meal and drink water. Labor often starts within hours of broken waters, and you may not get another chance to eat for a while.
- Sleep if you can. The work has not started yet. Bank the rest.
The contractions usually start within 12 to 24 hours. For most women, you will be at the hospital giving birth within 24 to 36 hours of waters breaking, and the path from the trickle on the sofa to the baby in your arms is shorter than it feels in the waiting.
What induction at 24 hours involves
If you reach the 24 hour mark with no contractions, your hospital will usually recommend induction. The standard pathway:
- Admission to the labor ward, IV cannula, baseline observations
- Antibiotics if you tested positive for GBS, or if you are at higher risk
- Hormonal drip (oxytocin, called Syntocinon in the UK or Pitocin in the US) to start contractions
- Continuous monitoring of the baby's heart rate
- The induction often produces labor within 6 to 12 hours
The contractions from an induction are often stronger and closer together than spontaneous contractions, so many women who induce after PROM opt for an epidural earlier. There is no wrong choice here.
We covered the full induction picture in [How Long Does Labor Induction Actually Take?](/blog/how-long-does-induction-take) and the conversation about declining or delaying in [What Happens if Labor Induction Does Not Work?](/blog/failed-induction).
When you should not wait
There are a few situations where the 24 hour timeline does not apply and you should be at the hospital immediately:
- Bright red or heavy bleeding alongside the broken waters
- Green, brown, or smelly fluid
- Reduced fetal movement at any point
- Fever, chills, or feeling generally unwell
- You are less than 37 weeks pregnant
- You feel the cord coming out (called cord prolapse, a true emergency)
- You have known placenta previa or other diagnosed complications
For any of these, call your maternity triage number and go in. The 24 hour window is for the standard, low-risk PROM at term.
What about home birth and birth centres if PROM happens
If you were planning a home birth or birth center delivery, PROM with no contractions usually means a re-think.
Most birth centres have a policy of either induction at the center (where they have the equipment) or transfer to hospital if labor has not started within a set time after PROM. Most independent midwives supporting home births will also recommend a hospital transfer if labor has not started within 24 hours and antibiotics are needed.
This is not a failure of your birth plan. It is the plan adapting to the new information. (We talked about that mindset shift in [Will My Birth Plan Actually Happen When Labor Goes Off Script?](/blog/birth-plan-reality).)
What to tell yourself on the sofa with damp pyjamas
The labor is coming. Probably within the next 24 hours, and almost certainly within 36. The version of you currently sitting with a leaky bump and a confused look on your face is hours away from being the version of you holding your baby.
You have not done anything wrong. PROM happens to almost 1 in 10 women at term and almost always ends well. The hospital systems for managing it have been refined for decades. The 24 hour timeline exists because it works.
While you wait: take your temperature, eat something, pack the last few things into the [hospital bag](/blog/what-to-pack-in-your-hospital-bag-week-by-week), put a towel on the car seat, and let the next part happen. The waiting room of PROM is one of the shortest waiting rooms of motherhood. You will not be in it for long.