There was no difference in the number of major abnormalities between the groups (four out of 111 exposed babies; three out of 172 unexposed babies). (Only foetuses exposed to corticosteroids during the first trimester of pregnancy were included in this analysis.)

Search

The databases MEDLINE (from 1966 to 1999), Embase (from 1988 to 1999) and Current Contents (1999) were searched. Bibliographies from retrieved papers were then reviewed. Controlled studies examining first-trimester systemic exposure for any corticosteroids, any dose, all conditions, any duration and all languages were included. Studies with fewer than ten patients and those which examined topical or inhaled steroids were excluded.

Search Results

Ten studies met the inclusion criteria (six cohort conducted from 1962 to 2000) and four case-control conducted from 1994 to 1999). The studies included women with various diseases including rheumatoid arthritis, asthma and inflammatory bowel disease. Participant numbers ranged from 22 to 50,282 in the cohort studies (totalling 51,470) and 1,396 to 56,557 in the case-control studies (totalling 71,705). Four examined the effects of corticosteroids and other medications and six examined only corticosteroids.

In the analysis of the six cohort studies, corticosteroid exposure was not associated with an increased risk of major malformations. Because the largest study (50,282 participants) did not distinguish between major and minor malformations and the purpose of this analysis was to examine major defects, the analysis was repeated without this study. A significant risk of major defects with corticosteroid exposure was then found (see Table 1). In the studies that specified the malformations, cleft palate was the most common defect with three cases among 390 corticosteroid exposed foetuses compared with no cases among 708 non-exposed foetuses.

Table 1. Risk of major malformations from cohort study analysis with and without largest trial.