Table 1. PICO criteria

Population terms	Teen* or adolescen* or youth or men or man or female or male or woman or women or reproductive age or child bearing age or childbearing age
Intervention terms	preconcept* or pre concept* or interconcept* or prepregnan* or pre pregnan* or pregnanc* plan* or plan* pregnanc* adj8 health program* or health education or health promot* or advic* or advis* or intervention* or care or assess* or risk or counsel* or screen* or folic acid supplement* or folate supplement*
Comparison	No preconception care or usual care
Outcomes	Primary outcomes will include but not limited to: knowledge of factors that affect health during the preconception period, and pregnancy outcomes including: maternal morbidity, prematurity and birth weight, fetal or neonatal mortality and morbidity, and fetal abnormalities.Secondary outcomes will include reduction in modifiable risk factors including but not limited to: weight, drug use, alcohol consumption, and smoking.(No specific key terms for outcomes were included when developing the search strategy owing to the heterogeneity of the outcomes measured across individual studies.)