What is defined as a trimester in pregnancy?

A trimester in pregnancy is defined as a period of approximately 3 months. This classification divides the typical 40-week term of pregnancy into three distinct segments: the first trimester (from conception through week 12), the second trimester (weeks 13 to 26), and the third trimester (weeks 27 to 40). Each trimester represents different stages of fetal development and maternal changes, which are crucial for expecting parents and healthcare professionals to monitor. Understanding this framework helps address various health considerations and prepares for the stages of prenatal care.

The other options do not align with standard medical definitions; a two-month period does not encapsulate a third of the pregnancy, 6 weeks is too short to define a trimester, and the period from conception to labor encompasses the entirety of pregnancy rather than the specific intervals defined as trimesters.