A pregnant woman’s fetus can be in possible danger if there is too little amniotic fluid surrounding the fetus. However, what you probably didn’t know is that too much amniotic fluid is also problematic. This condition, known as polyhydramnios, occurs within 1-2% of pregnancies. Because it can increase the risk of complications during pregnancy and delivery, doctors track fluid levels throughout the pregnancy. By the 36th week of pregnancy, usually there is approximately 1 quart of amniotic fluid. From week 37 onwards, the amount of fluid tends to decrease.
The earlier that polyhydramnios occurs in pregnancy and the greater the amount of excess amniotic fluid, the higher the risk of complications. The good news is that most cases of polyhydramnios are mild, result from a gradual buildup of amniotic fluid during the second half of pregnancy, and often resolve by themselves.
Polyhydramnios can develop because the mother is expecting multiples or has gestational diabetes. However, it can also develop as a result of fetal anomalies with disturbed fetal swallowing of amniotic fluid, fetal infection, fetal anemia, congenital malformations, genetic conditions, or because the fetus produces an increased amount of urine.
You might not know that you are suffering from polyhydramnios, if you have a mild case.
However, your doctor will suspect it if your uterus is excessively enlarged and he or she has trouble feeling the baby. If you are suffering from a more serious case, you might experience shortness of breath, discomfort in your uterus, contractions, swelling in the lower extremities and abdominal area, and the fetus being incorrectly positioned (such as a breech position).
The following are some of the serious complications associated with polyhydramnios:
- Premature contractions leading to preterm delivery
- Placental abruption
- Premature rupture of membranes
- Umbilical cord prolapse
- Longer labor
- C-section delivery
- Hemorrhage after labor
- Congenital abnormalities, abnormal size or positioning
- Dangerous positioning of the umbilical cord, which can cause the cord to become trapped against the fetus, limiting the oxygen supply
When treating polyhydramnios, the goal is to reduce the amount of amniotic fluid in the womb. Doctors do this by performing a reduction amniocentesis, where they draw fluid from the womb. A reduction amniocentesis must only be performed after careful diagnostic evaluation. Unfortunately, there is no medical consensus regarding how much amniotic fluid to withdraw, the rate at which it should be withdrawn, and the use of tocolytics (medication which delays preterm labor) or antibiotics.
Doctors may also prescribe medications such as prostaglandin synthetase inhibitors or sulindac. Prostaglandin synthetase inhibitors are not generally approved in pregnancy and are definitely not advised after the 28th week of pregnancy. If these agents are used for more than 48 hours, they can cause the opposite condition–reduced amniotic fluid or oligohydramnios, which has its own dangers.
The earlier that polyhydramnios occurs in pregnancy and the greater the amount of excess amniotic fluid, the higher the risk of complications. The good news is that most cases of polyhydramnios are mild and often resolve by themselves. More serious cases require ongoing medical care and possibly intervention.