Table 2: Risk of congenital malformations associated with trimethoprim use during the 12-week period prior to conception.

Reference groupAll unexposed children born 1997–2004All unexposed children born 1997–2004 adjustedaChildren born 1997–2004 by mothers with one or more prescription of mecillinam prior to pregnancy Children born 1997–2004
by mothers with no usage of prescription drugs prior to and during pregnancy

Major congenital malformations or (CI 95%)1.91 (1.28–2.87)1.87 (1.25–2.80)1.78 (1.15–2.77)2.05 (1.37–3.08)
All congenital malformations or (CI 95%)2.01 (1.45–2.78)1.96 (1.41–2.72)1.90 (1.33–2.72)2.18 (1.57–3.03)

aAdjusted for age, parity, usage of X-classified drugs, teratogenic infections, folate deficiency, myasthenia gravis, diabetes mellitus, alcoholism, amniocentesis, Sjogren’s syndrome, virilizing tumors, education, and income.