- AIDS (Disease) in adolescence--Africa (2)
- Adolescentes--Conducta sexual--Chile (1)
- Condom use--Japan (1)
- HIV infections--Africa (1)
- HIV infections--Africa--Prevention (1)
- Health education--Africa, East (1)
- Health education--Africa, Southern (1)
- Reproductive health--Africa, East (1)
- Reproductive health--Africa, Southern (1)
- Sex instruction for teenagers (1)
- Sex instruction for teenagers--Japan (1)
- Sex instruction--Japan (1)
- Sex role--Japan (1)
- Sexual abstinence (1)
- Teenage boys--Sexual behavior--Japan (1)
- Teenagers--Sexual behavior (1)
- Teenagers--Sexual behavior--Africa (1)
- Teenagers--Sexual behavior--Africa, East (1)
- Teenagers--Sexual behavior--Africa, Southern (1)
- Teenagers--Sexual behavior--Chile (1)
- Teenagers--Sexual behavior--Japan (1)