Objectives: To provide data on polyhydramnios associated with congenital anomalies in 225,669 consecutive pregnancies.
Material and methods: The information in this study came from births of known outcome recorded in our registry of congenital malformations. Routine ultrasonographic examination was performed. Polyhydramnios was diagnosed ultrasonographically. A case-control study allowed the examination of genetic and environmental causal factors of polyhydramnios associated with congenital malformations.
Results: The prevalence of this association was 1.28/1,000 (290 cases). Polyhydramnios associated with congenital malformations was diagnosed prenatally in 44.5% of the cases, 10.3% of the infants were stillborn. Forty-one percent of the cases had more than one malformation, 14.5% had a chromosomal aberration, and 20.0% had multiple malformations that do not constitute a syndrome. The more frequent malformations associated with polyhydramnios were cardiac, digestive, central nervous system, musculoskeletal, and urinary. There was increased parental consanguinity. The incidence of polyhydramnios and congenital anomalies among first-degree relatives was 4.1% and first-degree relatives had more malformations than controls (6.2 vs. 3.2%, p < 0.05). Threatened abortions and diabetes mellitus were significantly more frequent among mothers of children with congenital malformations associated with polyhydramnios than among controls.
Conclusions: Our study demonstrated that careful fetal examination has to be performed when polyhydramnios is diagnosed as congenital malformations are often associated with polyhydramnios. We recommend the use of fetal chromosome analysis and careful ultrasonographic examination in every pregnancy complicated by polyhydramnios.