Understanding Polyhydramnios: What to Expect During Pregnancy

Question
This relates to my daughter-in-law. She is expecting her first child on 8th July.

She had a scan today and was told that there is too much fluid. They chatted about this and told her that they want to keep an eye on this and want to see her again next week. They did not tell her what they are worried about and now she is concerned.

Many thanks for your help.

Anne Close

Answer
Polyhydramnios is a pathologic accumulation of amniotic fluid. It is defined as more than 2000ml at any gestational age, or an Amniotic Fluid Level of greater than 20cm at term.  Mild increases in fluid are usually insignificant. Larger iincreases in fluid volume are associated with increased perinatal morbidity due to preterm labor, cord prolapse, and congenital malformations. Between 16% and 66% of cases are idiopathic (no discernable cause). The remaining cases are usually due to increased fetal urine  production or esophageal problems (the baby is not swallowing the fluid). As you know, amniotic fluid is swallowed and urinated by the baby, if there is a failure of swallowing, there will be an increased amount of fluid. If there is a failure of the fetal kidney, there will be less urinatiion and a decrease in the amniotic fluid.  It is seen commonly in gestational diabetes. Minor and moderate degrees of hydramnnios with some discomfort can be managed expectantly until the onset of labor or spontaneous rupture of membranes. In more severe cases or if the patient develops difficulty in breathing, abdominal pain, or difficulty walking, treatment is necessary. Amnioreduction is the most common method of treatment.  Pharmacologic treatment is with medications that decrease fetal renal blood flow and lower fetal urine production.  Most cases are not severe and can be just followed closely. Don't worry. Your daughter-in-law will have multiple sonograms and probably will do fine.