Health & Fitness

What Is Gestational Age?

Gestational age is the standard way of measuring how far along a pregnancy is, counted in weeks from the first day of the last menstrual period rather than from conception. Because conception usually occurs about two weeks later, gestational age is about two weeks more than the fetal age.

Term Categories

Under current obstetric definitions, 37 weeks 0 days to 38 weeks 6 days is early term, 39 weeks 0 days to 40 weeks 6 days is full term, and 41 weeks is late term.

Trimesters

Pregnancy is commonly divided into three trimesters of roughly 13 to 14 weeks each.

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🔗 Related Terms

Estimated Due Date (EDD) Menstrual Cycle Fertile Window

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Last updated: September 27, 2026. This definition is for general educational purposes only. It is not financial, investment, tax, legal, or medical advice, and it does not recommend any product or course of action. For decisions about your own situation, consult a qualified professional.