First-trimester nonsystemic corticosteroid use and the risk of oral clefts in Norway.

PURPOSE: Exposure of pregnant mice to corticosteroids can produce oral clefts in offspring. Although data in humans are more mixed, recent reports have suggested that dermatologic steroids are associated with oral clefts. METHODS: We investigated maternal first-trimester exposure to corticosteroids (focusing on dermatologic uses) and oral clefts in offspring using two population-based studies. The Norway Cleft Study (1996-2001) is a national case-control study including 377 infants with cleft lip +/- palate (CLP), 196 infants with cleft palate only (CPO), and 763 controls. The Norwegian Mother and Child Cohort Study (MoBa, 1998-2008) is a national birth cohort including 123 infants with CLP, 61 infants with CPO, and 551 controls. RESULTS: In the case-control study, there was the suggestion of an association of dermatologic corticosteroids with both CLP (adjusted OR [aOR], 2.3; 95% confidence interval [CI], 0.71-7.7) and CPO (aOR, 3.4; CI, 0.87-13). There was no evidence of this association in the cohort data (odds ratio for CLP, 1.2; CI, 0.50-2.8 and odds ratio for CPO, 1.0; CI, 0.30-3.4), although exposure to dermatologic steroids was less specifically ascertained. There were no associations with other types of corticosteroids. CONCLUSIONS: Our data add to the suggestive but inconsistent findings for this association.