Congenital toxoplasmosis: systematic review of evidence of efficacy of treatment in pregnancy.

OBJECTIVE To summarise the evidence that treating toxoplasmosis in pregnancy reduces the risk of congenital toxoplasma infection and improves infant outcomes. DESIGN Systematic review of studies comparing at least two concurrent groups of pregnant women with proved or likely acute toxoplasma infection in which treatments were compared with no treatment and outcomes in the children were reported. SUBJECTS Studies were identified from Medline (1966-97), Pascal (1990-7), Embase (1993-7), and Biological abstracts (1993-5) plus contact with experts in the field, including the European Research Network on Congenital Toxoplasmosis. MAIN OUTCOME MEASURE Proportion of infected children at 1 year born to infected pregnant women who were or were not treated. RESULTS Out of 2591 papers identified, nine met the inclusion criteria. There were no randomised comparisons, and control groups were generally not directly comparable with the treatment groups. Congenital infection was common in treated groups. five studies showed that treatment was effective and four that it was not. CONCLUSION It is unclear whether antenatal treatment in women with presumed toxoplasmosis reduces congenital transmission of Toxoplasma gondii. Screening is expensive, so the effects of treatment and impact of screening programmes need to be evaluated. In countries where screening or treatment is not routine, these technologies should not be introduced outside carefully controlled trials.