Pregnancy is the process by which the zygote, the result of the union of sperm and egg in a woman’s body, develops and grows in the uterus. Pregnancy usually lasts for 40 weeks, but can sometimes last between 37 and 42 weeks. Each week of pregnancy includes the development of the baby’s organs and changes in the mother’s body.
What are the Basic Stages of Pregnancy?
Pregnancy usually begins when the egg meets the sperm in the fallopian tubes. This union results in the formation of a zygote. The zygote divides, increasing the number of cells and these divisions form a small embryo. The dividing cells form a blastocyst and this cluster of cells implants in the uterus.
After implantation, the cluster of cells forms an embryo, which later becomes a fetus. During the embryo and fetus stages, organs and systems develop. The heart begins to beat, organs fall into place and a rapid growth process begins.
Trimesters of Pregnancy
Pregnancy is usually divided into three trimesters
First Trimester (weeks 1-12): The baby begins to develop its organs, a heartbeat can be heard and signs of pregnancy appear.
Second Trimester (13-26 weeks): The baby starts to move, gender can be determined, and the mother usually feels more comfortable.
Third Trimester (from week 27): The baby grows rapidly, the lungs develop, the mother can gain more weight and preparation for delivery begins.
Birth
Pregnancy ends with birth. Birth usually happens when the uterus contracts, the water breaks (the amniotic sac bursts) and the baby comes out through the birth canal. Pregnancy can involve different experiences for each woman. Regular medical check-ups are important throughout pregnancy. These check-ups are done to monitor the health of the mother and baby, and to recognize and treat potential problems. Regular exercise, healthy eating and sleep are also important for a healthy pregnancy.