Definition - What does Amnioreduction mean?
An amnioreduction is the repeated removal of a large volume of amniotic fluid (bag of waters) via a procedure called amniocentesis or amniotic fluid testing. The procedure aims to normalize excessive fluid levels caused by a condition called polyhydramnios. It relieves discomfort in the mother, improves blood flow from the placenta to the uterus (particularly in the setting of twin to twin transfusion syndrome/TTTS), and prevent premature delivery.
FertilitySmarts explains Amnioreduction
Too much water in the bag that surrounds the baby in the uterus exerts pressure on the mother and baby, causing difficulty breathing in the mother, premature delivery in the fetus, and several other complications. Excessive amniotic fluid is also produced in the recipient twin in TTTS and exerts pressure on the donor twin, interfering with its growth. Amnioreduction serves to enhance blood flow to the donor twin by lowering pressure inside the bag of waters.
The doctors avoid amnioreduction in the presence of following factors:
- Bleeding disorder in the mother or fetus
- Premature uterine contractions and labor
- Suspected infection of the coverings of the developing fetus (chorioamnionitis)
An amnioreduction is performed under ultrasound guidance. A sterile needle is advanced into the amniotic fluid through the mother’s abdomen and the fluid drained. Vacuum tubes and vacuum bottles may be used to assist drainage. The fetal well-being is monitored by non-stress testing at the same time. The goal is to reduce pressure on the surface of the placenta and to limit the mother's discomfort.
Women undergoing the procedure are at risk of premature rupture of membranes, premature separation of the placenta, and chorioamnionitis.