Norway Facial Clefts Study

This was a population-based case-control study of all Norwegian infants born with cleft lip and/or palate over a five-year period. The study was jointly supported by the U.S. National Institute of Environmental Health Sciences (NIEHS) and the Norwegian National Institute of Public Health (NIPH) and Medical Birth Registry of Norway (MBR). Cases were identified through the two surgery clinics that treated all clefts in Norway. Controls were randomly selected from all live births through the MBR. Mothers completed two self-administered questionnaires; one regarding exposures before and during pregnancy, the other regarding their diet during their early months of pregnancy. Biological specimens for DNA testing (blood samples, buccal swabs) were collected from cases, controls, and mothers in order to describe possible gene-environment interactions. With approximately 750 cases and 1100 controls, this was one of the largest and most complete field studies of facial clefting yet conducted. Protocol #OH96-E-N006: Svangerskap, arv, og Milijo (Pregnancy, Heredity & Environment)