"40 weeks" typically refers to the average duration of a human pregnancy, which is counted from the first day of a woman's last menstrual period. This period is divided into three trimesters, with each trimester lasting about 13 weeks. The 40 weeks culminate in childbirth, when the baby is born. In addition to pregnancy, "40 weeks" can also represent a standard work year, often used in discussions about employment and labor. In this context, it signifies the typical full-time work schedule, excluding holidays and vacations, contributing to a person's annual income and productivity.