CYTOGENETIC STUDIES IN PREGNANCY WASTAGE

Abstract

In a consecutive series of 1,040 families seen in our Genetic Counseling Program, 58 families were referred because of pregnancy loss or wastage (2 or more spontaneous abortions or stillbirths). In 41 families cytogenetic studies were done on both parents and in four instances only the mother was studied. One mother was found to be a mosaic Turner's syndrome (46XX/45X); two mothers and one father were balanced translocation carriers (46XX, t (13q-; 3q+); 46XX t (17p-; 3q+); 46XY, t (4q-; 13+)). Of the 78 parents in whom cytogenetic studies were carried out, five families had children with trisomy 21 in addition to two miscarriages or one miscarriage and a stillbirth. Six families had children with anomalies of the nervous system (anencephalus, hydrocephalus or meningomyelocele). In one mother pregnancy wastage was associated with maternal hyperthyroidism. In two other families fetal wastage, which occurred late during pregnancy, could be attributed to blood group incompatibilities. Thus, in 40 families no obvious cause could be found for fetal loss. The overall percentage of obvious chromosomal abnormalities in our series is approximately 10%, and exceeds previously reported frequencies of significant cytologic aberrations in couples who present with fetal wastage.