Calculate your estimated due date and pregnancy week based on your last menstrual period.
Pregnancy tracking and baby development
Pregnancy lasts an average of 40 weeks (280 days) and is calculated from the first day of your last menstrual period. Actual conception typically occurs about 2 weeks after the last menstrual period. The estimated due date is an approximation, and babies typically arrive between weeks 37-42. Pregnancy is divided into three trimesters: The first trimester (weeks 1-12) is the critical period when organs form. The second trimester (weeks 13-26) is when the baby grows rapidly and the mother is most comfortable. The third trimester (weeks 27-40) is the final stage when the baby prepares for birth. Regular prenatal care, healthy nutrition, folic acid supplementation, adequate rest, and stress management are important for a healthy pregnancy. Alcohol, smoking, and certain medications should be avoided. Every pregnancy is different, so it's crucial to consult with your doctor regularly and receive personalized recommendations.
Find answers to common questions
Pregnancy duration is calculated from the first day of your last menstrual period. Average pregnancy is 40 weeks or 280 days. This calculation is known as Naegele's rule.
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