Study designs of evaluations included in the review
Cohort and case-control studies (with a control group not receiving NF) were included.
Specific interventions included in the review
NF given as an antibiotic treatment during pregnancy.
Participants included in the review
Pregnant women were included.
Outcomes assessed in the review
The rates of major foetal malformations were assessed.
How were decisions on the relevance of primary studies made?
Two independent investigators made decisions based on the following criteria: human studies of maternal NF exposure in first trimester of pregnancy, with outcomes of major or minor foetal malformation published in any language. The studies were assessed without knowing the results.