KARYOTYPIC ABNORMALITIES AND HYDRAMINIOS - ROLE OF AMNIOCENTESIS

Hydramnios complicates up to 1.6% of pregnancies, with major fetal mal formations found in an average of 20% of patients with hydramnios. Chr omosomal abnormalities, although associated with some conditions in wh ich hydramnios is present, have not been reported to complicate a sign ificant percentage of hydramnios cases. Data from 45 patients admitted during the period January 1, 1985-May 31,1990, were analyzed. All pat ients had hydramnios sufficiently severe to merit hospitalization for diagnosis and/or treatment. Amniocentesis was performed at the discret ion of the attending physician and not under a specific protocol. The incidence of major fetal structural malformations was 36%. Of patients in whom amniocentesis was performed, 22% were found to have karyotypi c abnormalities, none of which was specifically suspected prior to the amniocenteses. Neither the estimated gestational age nor the assessme nt of the amount of amniotic fluid differed between those with karyoty pic abnormalities and those with normal chromosome complements. This i nformation suggests that both advanced ultrasound studies and amniocen tesis are beneficial in the evaluation of hydramnios.