The term pregnancy interval refers to the time between two successive pregnancies. There are several synonyms that can be used to describe this concept, including interpregnancy interval, birth spacing, and interbirth interval. These terms refer to the same idea of the length of time between the end of one pregnancy and the beginning of the next. Pregnancy spacing can play an important role in maternal and child health outcomes. Adequate spacing between pregnancies can reduce the risk of preterm delivery, low birth weight, and complications during pregnancy and childbirth. Women and their healthcare providers should be aware of the importance of pregnancy spacing and the synonyms used to describe this concept.