Maternal risk factors in cleft lip and palate: case control study.

Three hundred and six mothers who gave birth to babies with cleft lip, or palate, or both, were matched with 306 who gave birth to healthy babies in the same area during the same time period. Significantly more babies in the cleft group had a family history of clefts (48/306 compared with 7/306, P<0.0001). In the cases studied, combined cleft lip and palate was significantly more common among boys (82/157 compared with 57/149, P=0.02) and cleft palate alone among girls (48/149 compared with 22/157, P=0.0002). Significantly more mothers reported some sort of illness during early pregnancy (101/306 compared with 74/306, P=0.02). There were no differences between the groups as far as dietary preferences were concerned but during early pregnancy the mothers who gave birth to babies with defects tended to drink less alcohol (<1 unit/week) (236 compared with 199, P=0.001) and less coffee (<1 cup/week) (159/306 compared with 131, P=0.03). However, in each case similar proportions gave up once the pregnancy was confirmed. Large multicentre studies are required to confirm or refute these findings.