Water breaking before 37 weeks of pregnancy can pose a risk to your baby. Here’s how to tell the difference between amniotic fluid and other types of vaginal discharge.
Amniotic fluid plays several roles during pregnancy: it keeps the baby at a stable temperature, cushions it from outside blows, and allows it to move and develop its muscles in the womb.
It’s not always easy to tell the difference between amniotic fluid and vaginal secretions or urine leaks. Nevertheless, it’s important to pay close attention, as a loss of amniotic fluid (water breaking) before 37 weeks of pregnancy can pose a risk to the baby. Among other things, it can signal that you’re in labour.
Is it amniotic fluid?
To find out if your water is breaking, put on a sanitary pad and continue your activities for 30 minutes. If you’re losing amniotic fluid, the pad will be fully soaked. If not, the discharge may be vaginal secretions or urine leakage.
It’s also possible that your amniotic fluid is trickling out slowly because the sac is only partially ruptured. In this case, it may be more difficult to determine whether your water has broken.
To identify your discharge, pay attention to its appearance. Try to determine how heavy and frequent the flow is. If you’re losing amniotic fluid, your discharge will be continuous, clear, and odourless, like water. The flow will increase when your baby moves or if you change position.
If you suspect that you’re losing amniotic fluid, call the hospital’s birthing unit or visit your birth location. A health care professional will administer a test to help you determine whether your water is breaking. If it is, you’ll need to remain at your birth location, even if you aren’t experiencing contractions.
Generally, contractions should start within hours of your membranes rupturing. If labour doesn’t begin, your medical team may opt for induction.
When the membranes rupture, the risks of infection and umbilical cord compression increase. For this reason, it’s recommended that pregnant women go to their birth location within 2 hours of their water breaking. The medical team will monitor for signs of infection and decreased movement of the baby.
Inducing labour is recommended if the mother is full-term and contractions still haven’t started after 24 hours. Exceeding this time frame has been associated with a higher risk of caesarean section. Labour induction can also be done earlier if the mother is a carrier of group B streptococcus. However, if she’s not full-term, the medical team will try to prolong the pregnancy while preventing complications for both mother and baby.
Is it vaginal secretions?
Vaginal secretions are heavier and more liquid at the end of pregnancy and when the ambient temperature is warmer (e.g., in summer). They may dampen but not soak your underwear.
If your vaginal secretions change colour, have a foamy texture or a bad smell, or feel itchy, see a doctor. These symptoms could indicate an infection.
Is it the mucus plug?
The mucus plug—a collection of gelatinous secretions resembling egg whites—protects the uterus from infection during pregnancy. After the 35th week of pregnancy, some women pass their mucus plug, which comes out as jelly-like discharge and may be tinged with pink blood.
However, this doesn’t mean that labour is imminent. Rather, it signals that your cervix is preparing for your baby’s delivery. You therefore don’t need to go to your birth location if you lose all or part of your mucus plug.
Is it urine leakage?
Urine leaks usually occur after physical effort, certain movements, sneezing, or coughing. The flow of urine stops when your bladder is empty. You may also feel a loss of amniotic fluid when you sneeze or cough. However, it will be odourless, whereas urine will have a distinct smell.
Things to keep in mind
Water breaking can signal that you’re in labour.
It can be difficult to tell the difference between amniotic fluid and vaginal secretions or urine leaks.
If you’re losing amniotic fluid, you must go to your birth location even if you aren’t experiencing contractions.
Scientific review: Amélie Guay, M.Sc., PNC(C), perinatal advanced practice clinical nurse, CHUM
Research and copywriting: The Naître et grandir team
Updated: November 2020
Photo: 123RF/Paul Vasarhelyi
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CHUM Birthing Centre. “Your delivery at the CHUM Birthing Centre.” Montreal, Quebec, 2019. www.chumontreal.qc.ca
Doré, Nicole, and Danielle Le Hénaff. From Tiny Tot to Toddler: A practical guide for parents from pregnancy to age two. Quebec City, Institut national de santé publique du Québec. www.inspq.qc.ca
Ladewig, Patricia, et al. Maternal & Child Nursing Care. 3rd ed., Upper Saddle River, Prentice Hall, 2011, 2,016 pp.
Salus Global Corporation. “Rupture prématurée des membranes.” MOREOB 19th ed., Mississauga, Ontario, 2020.
Salus Global Corporation. “Prise en charge du travail.” MOREOB 19th ed., Mississauga, Ontario, 2020.