Drug use during early pregnancy - The impact of maternal illness, outcome of prior pregnancies and socio-demographic factors

Objective: Socio-demographic factors have been associated with drug use in pregnancy. However, information on maternal illness has rarely been include d in previous studies. The aim of this study was therefore to estimate the impact of maternal illness and prior pregnancy outcome on the use of analge sics/antipyretics anti-infectives and antihistamines in early pregnancy con trolling for socio-demographic factors. Methods: One thousand nine-hundred and forty-five parous pregnant women fro m Norway and Sweden were included in an interview study. Information on dru g use, obstetric history, maternal illness and socio-demographic factors wa s collected by specially trained midwives at gestational week 17 and form t he basis for the present analyses. Results: After control for socio-demographic factors, reported illness was associated with the use of analgesics/antipyretics, anti-infectives and ant ihistamines during early pregnancy. The use of analgesic/antipyretic and an ti-infective drugs differed between study sites. Sociodemographic factors s uch as age, parity, marital status, education, occupation and smoking habit s did not influence drug use in the multivariate analysis. Conclusion: Maternal illness during pregnancy was associated with drug use in early pregnancy. When studying factors related to drug use during pregna ncy, it is important to include information on maternal illness. Socio-demo graphic factors may be confounders and lead to erroneous conclusions about the factors related to drug use.