Trimester

Trimester is a term used to describe the three stages of human pregnancy. Each trimester lasts for approximately three months. During each trimester, the fetus undergoes a period of rapid growth and development. The first trimester is from week 1 to the end of week 12. During this stage, the fertilized egg implants in the uterus and the placenta begins to form. During the first trimester, the fetus is most vulnerable to damage, and the risk of miscarriage is highest. This is also when the baby’s major organs, such as the heart, lungs and brain, begin to develop. The second trimester is from week 13 to the end of week 26. During this stage, the fetus continues to grow and develop. The baby’s movements can be felt and the fetus is able to hear and respond to sound. The mother may begin to feel movement from the baby around this time. The third trimester is from week 27 to the end of the pregnancy. During this stage, the baby continues to grow and develop. The baby’s organs and systems are maturing and the baby is preparing for birth. The mother’s body changes in preparation for labor and delivery.