RT Journal Article SR Electronic T1 Morbidity and drugs in pregnancy JF The Journal of the Royal College of General Practitioners JO J R Coll Gen Pract FD British Journal of General Practice SP 631 OP 645 VO 25 IS 158 A1 The Birmingham Research Unit of the Royal College of General Practitioners YR 1975 UL http://bjgp.org/content/25/158/631.abstract AB In a prospective study involving 9,000 pregnant women, no cause-and-effect relationships have been established between morbidity recorded or drugs taken during early pregnancy and subsequent congenital malformations. The relationships that have been identified are largely explained by the influence of a history of a previous abnormal outcome of pregnancy (including abortion) and, to a lesser extent, by the influence of maternal anxiety on the diagnosis of doubtful malformations. It is also very unlikely that any drug in common use in 1964 had even a minor influence on congenital malformations recognisable in the first six weeks of life.