Pregnancy Week Calculator
Find out how many weeks and days pregnant you are and what to expect at your stage.
Pregnancy Week by Week
Pregnancy lasts approximately 40 weeks from the first day of your last menstrual period. These 40 weeks are divided into three trimesters, each bringing different milestones and changes for both you and your developing baby. Understanding what happens week by week can help you know what to expect and when to seek medical advice.
During the first trimester (weeks 1-13), your baby transforms from a cluster of cells into a recognizable embryo with a beating heart, forming brain, and the beginnings of all major organs. The second trimester (weeks 14-27) is marked by rapid growth, the ability to feel your baby move, and the development of unique features like fingerprints. The third trimester (weeks 28-40+) focuses on weight gain and lung maturation as your baby prepares for life outside the womb.
Every pregnancy is unique, and your experience may differ from what you read online or hear from friends. What matters most is maintaining regular prenatal care, eating a balanced diet, staying active with your provider's approval, and paying attention to your body. If anything feels wrong or different, do not hesitate to contact your healthcare team.