Amniotic fluid tests when you think your waters have broken

The assessment usually combines your description of the leak with a sterile speculum examination and, when needed, a sample of vaginal fluid. A test result is interpreted alongside the examination rather than used on its own.

During a speculum examination, the clinician looks for fluid collecting in the vagina or coming through the cervix. A swab may check the fluid's chemical pattern or proteins associated with amniotic fluid. Urine, vaginal discharge, semen, blood and infection can sometimes complicate interpretation, so an unclear result may lead to observation, a repeat examination or an ultrasound assessment of the fluid around the baby.

A negative result does not always settle the question when leakage is intermittent or the history strongly suggests ruptured membranes. Ongoing wetness deserves reassessment even after an earlier test was reassuring.

Put on a clean sanitary pad, note the time the leaking began, and observe the fluid's colour, smell and whether it continues. Do not insert a tampon or anything else into the vagina. Contact your maternity unit promptly for advice, because an examination is the reliable way to distinguish amniotic fluid from urine or discharge.

Bring your pregnancy records and tell the team about contractions, bleeding, fever, recent intercourse and your baby's movements. If your waters are confirmed to have broken before 37 weeks, the team will assess for preterm labour and infection and discuss monitoring and treatment appropriate to your pregnancy.

Seek urgent maternity assessment for a gush or persistent trickle of fluid, especially before 37 weeks. Go urgently if the fluid is green, brown, bloody or unpleasant-smelling, or if you have fever, significant abdominal pain, regular contractions, heavy bleeding, feel unwell, or notice reduced or changed baby movements.

Do not wait for a home test if you have any of these warning signs. If something appears to be protruding from the vagina after a sudden gush, call emergency services and avoid touching it.

Ask which findings support or rule against ruptured membranes, whether you need repeat testing, and how your baby's wellbeing will be checked. You can also ask what changes in fluid, contractions, temperature or movements should bring you back immediately and whether any activity restrictions apply while the result remains uncertain.