Polyhydramnios means there’s too much amniotic fluid in your uterus during pregnancy. A mild case of polyhydramnios may not cause any symptoms or problems, but more severe forms may require treatment.
Polyhydramnios is when you have too much amniotic fluid during pregnancy. Amniotic fluid is the liquid that surrounds the fetus in your uterus. Amniotic fluid plays a significant role in the fetus's growth and development.
This condition usually happens in the second half of pregnancy, but it may occur as early as 16 weeks into pregnancy. Mild polyhydramnios doesn’t usually cause complications. Your pregnancy care provider will monitor you closely in case your condition worsens and treatment is necessary.
Polyhydramnios is rare and affects about 1% of pregnancies.
Some people don’t experience any symptoms because the condition is mild. If you have a more severe case of polyhydramnios, you could have these symptoms:
When your uterus gets larger, it puts pressure on nearby organs like your lungs, stomach, rectum and bladder. This added pressure is typically the cause of your symptoms.
Your pregnancy care provider may suspect you have too much amniotic fluid if:
For most people (especially people with mild cases), the cause of polyhydramnios is unknown.
Moderate to severe polyhydramnios could be caused by the following:
Your pregnancy care provider will measure your abdomen (a measurement called fundal height) to determine if your uterus is too large. Typically, that means you’re measuring two or more weeks ahead of your expected due date.
They’ll use an ultrasound to measure how much amniotic fluid is in your uterus. There are two ways to do this: amniotic fluid index (AFI) and maximum vertical pocket (MPV). AFI checks how deep the fluid is in four areas of your uterus. Your provider adds these numbers up. MPV measures only the deepest area of your uterus to check for fluid volume. If one of these tests shows you have polyhydramnios, your provider will likely order additional tests to check for congenital disorders, diabetes or other conditions. Some of these tests may include:
Polyhydramnios is generally not treated if it’s a mild case or if you’re at the end of your pregnancy. Your provider may schedule additional appointments to monitor your condition. In most cases, monitoring your pregnancy closely is the best plan.
Treatment may be needed if you have severe polyhydramnios. In some cases that means treating the underlying condition (like diabetes) causing polyhydramnios. Other treatment options include:
Too much amniotic fluid in your uterus puts pressure on your nearby organs and causes pregnancy complications. The condition is usually more serious if it occurs early in pregnancy because there’s more time for amniotic fluid to continue to build up. The excess fluid itself is not harmful to the fetus.
Other complications of too much amniotic fluid include:
No, you can’t prevent polyhydramnios. If you’ve been diagnosed with gestational diabetes or had diabetes before pregnancy, managing your blood sugar levels is one precaution you can take.
People with polyhydramnios may be monitored more closely for the remainder of the pregnancy. You can expect more frequent appointments as well as more ultrasounds to measure amniotic fluid volume.
Your birthing experience shouldn’t be too different than someone without polyhydramnios. Your baby’s heartbeat will be evaluated during labor to make sure they aren’t going through too much stress. You may also pass a large amount of amniotic fluid as you give birth. A pediatrician will evaluate your baby immediately after birth and make sure they’re healthy.
Mild cases of polyhydramnios shouldn’t affect your baby. In diabetes-related cases, the fetus may grow too large for a vaginal delivery. Severe cases of polyhydramnios may lead to premature labor and your baby being born early. If your pregnancy care provider believes your condition needs treatment, they’ll suggest the best path forward to ensure you and your baby are taken care of.
Yes, most people will not have pregnancy complications from too much amniotic fluid and will have a healthy baby.
You may need a cesarean section (C-section) if your provider believes a vaginal delivery is too risky. Your chances of having a C-section are only slightly increased.
If you’re diagnosed with polyhydramnios, you can try to relieve your worries by doing the following:
Contact your pregnancy care provider if you have any new symptoms, begin feeling overly full in your belly or notice your abdomen gets bigger suddenly. If your provider diagnoses you with any health condition during pregnancy, it’s very important to attend all your prenatal appointments and ultrasounds. Ask them what you can expect if you have polyhydramnios, so you can call them if you believe your condition is worsening.
A note from Cleveland Clinic
Polyhydramnios is a complication of pregnancy that typically doesn’t require treatment. Your provider will watch you closely and may recommend an induction. If you’ve been diagnosed with having too much amniotic fluid, it’s OK to be concerned. Talk to your pregnancy care provider about your concerns and ask any questions you have about the condition. Your provider is there to support you and make sure you and your baby are healthy. Most people with polyhydramnios have healthy babies without complications.
Last reviewed by a Cleveland Clinic medical professional on 08/10/2022.
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