Isolated polyhydramnios: Is a genetic evaluation of value?

Area of Science:

• Perinatology
• Medical Genetics
• Reproductive Medicine

Background:

• Isolated polyhydramnios is a condition of excessive amniotic fluid without other fetal anomalies.
• The risk of underlying genetic abnormalities in isolated polyhydramnios requires further investigation.

Purpose of the Study:

• To analyze the risk for genetic aberrations in pregnancies with isolated polyhydramnios.
• To evaluate pregnancy outcomes associated with isolated polyhydramnios.

Main Methods:

• Retrospective study of singleton pregnancies with isolated polyhydramnios undergoing genetic amniocentesis (2016-2021).
• Collected data included maternal demographics, sonographic findings, chromosomal microarray results, and pregnancy outcomes.
• Whole exome sequencing was utilized for postnatal diagnosis of single gene disorders.

Main Results:

• Three cases (3.2%) had chromosomal abnormalities, including trisomy 21 and 22q21.1 microdeletion.
• One case of Prader-Willi syndrome and one of Bartter syndrome were identified.
• Postnatal whole exome sequencing identified single gene disorders in two infants.

Conclusions:

• Isolated polyhydramnios is associated with a notable risk of genetic aberrations.
• Advanced genetic testing, including whole exome sequencing, shows potential in identifying genetic causes.
• Further research is warranted to establish the role of advanced genetic technologies in managing isolated polyhydramnios.