Contraceptives, Oral

**Definition:** Compounds, usually hormonal, taken orally in order to block ovulation and prevent the occurrence of pregnancy. The hormones are generally estrogen or progesterone or both.

**Tree numbers:** - D27.505.696.875.360.276.210 - D27.505.954.705.360.276.210

**Synonyms:** - Oral Contraceptive - Oral Contraceptives