What is polyhydramnios?

Polyhydramnios is a condition which affects the uterus of a pregnant woman. In this condition, too much amniotic fluid (the liquid that surrounds the baby in the womb) collects in the uterus. When this happens, the uterus becomes larger than normal.

Amniotic fluid has a significant role in the baby’s growth. Typically, amniotic fluid is swallowed by the baby in utero and then urinated out. This steadies the amount of fluid in the uterus.

This condition can present itself as soon as 16 weeks into the pregnancy. However, more often it will show as the pregnancy progresses into later weeks.

How common is polyhydramnios?

Polyhydramnios is considered rare. This condition affects roughly 1 percent of pregnancies.

Who is affected by polyhydramnios?

Any pregnant woman can be affected by polyhydramnios. However, it is distinguished as a rare condition.

What are the symptoms of polyhydramnios?

For women experiencing a mild case of polyhydramnios, there may not be any symptoms. Women experiencing a more severe form of the condition could have these symptoms:

  • Sensation of tightness in stomach
  • Indigestion
  • Difficulty with bowel movements (constipation)
  • Producing less urine
  • Enlargement of vulva
  • Breathing troubles
  • Swelling of leg, thigh, hip, ankle and/or foot

What causes polyhydramnios?

For most women, the cause of their polyhydramnios condition remains a mystery. Women with mild cases most likely have symptoms due to the increasing amount of fluid in their uterus. Moderate to severe polyhydramnios could be caused by the following:

  • Birth defect affecting the baby’s ability to swallow
  • High blood glucose levels (mother has diabetes either before or after becoming pregnant)
  • Carrying identical twins with transfusion syndrome (TTTS)
  • Differing blood types (mother has Rh-negative, baby has Rh-positive)
  • Problem in the baby’s stomach
  • Issues with the placenta
  • Too much fluid in the baby
  • Complications with the heart rate of the baby
  • Baby develops an infection

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