A prospective study of drugs and pregnancy. 4. Miscellaneous drugs.

The results are presented of a prospective study on drug use during pregnancy involving antibiotics, analgesic drugs and iron and vitamin preparations. The study was conducted in Malmö between 1963 and 1965. No unfavourable effect of the use of antibiotics, mainly penicillin and sulphonamides, could be demonstrated. Among 15 women who had an infant with hypospadias, three had used penicillin during the first trimester, but this may well be coincidental. Analgesic drug use shows a variability which resembles that previously described for psychopharmaca. No effect on the malformation rate or infant survival could be found. A possible lengthening of the mean duration of pregnancy occurred after the use of analgesic drugs during the 2nd or 3rd trimesters. Women who are going to have a dead or malformed infant use iron and/or vitamin preparations less often during late pregnancy than women who prove to have a normal infant. When such drugs were used, the percentage of pregnancies ending in birth before the 38th week is reduced, and the birth weight among term babies is higher. The associations between pregnancy outcome and the use of iron and vitamin preparations is probably indirect, due to social factors associated with drug use.