The use of corticosteroids during pregnancy does not appear to be associated with an increased risk of orofacial clefts in infants, according to an article in CMAJ (Canadian Medical Association Journal) (pre-embargo link only) http://www.cmaj.ca/embargo/cmaj101063.pdf.
Many previous studies have shown associated risks with use of oral corticosteroids, although they were small studies.
Corticosteroids are used for asthma, allergies, eczema and psoriasis, autoimmune diseases and cancer. Use of corticosteroids during pregnancy has been associated with orofacial clefts in animals and similar risks in humans are suspected.
This study, by researchers based in Copenhagen, Denmark, looked at data on 832 636 live births over the study period from January 1996 to September 2008. They used data from the Danish Medical Birth Registry, the Danish Prescription Drug Register and the National Hospital Discharge Register.
In the study group, 163 494 women (19.6%) used corticosteroids once or more in the four weeks before pregnancy up to birth. The most common were dermatological corticosteroids (43.3%), other topical solutions (e.g. eye drops or ear drops), nasal sprays (21.6%), inhalants, (14.3%) and oral medications (4.2%). First trimester use occurred in 51 973 (6.2%) of women. The researchers identified 1232 orofacial clefts in infants up to age 1 year.
"Women who used any corticosteroid during the first trimester were not significantly more likely to bear offspring with a cleft lip with or without a cleft palate or a cleft palate alone than women who did not use any corticosteroid during the first trimester," write Dr. Anders Hviid and Ditte Mølgaard-Nielsen, Statens Serum Institute, Copenhagen, Denmark.
"However, the use of dermatologic corticosteroids was associated with an increased risk of cleft lip with or without cleft palate," the authors state, although oral, inhalants, nasals or other topical corticosteroids were not. They suggest this association may be from multiple statistical comparisons rather than causality.
They conclude, "our results add to the safety information for a class of drugs commonly used during pregnancy." They caution that the apparent lack of an association in this study supports that moderate to strong risks are unlikely, but not that corticosteroids are completely safe.