Pregnancy begins when an ovum in the female is fertilized by a spermatozoon from the male. The embryo starts to form in the uterus and grows to become a foetus.

The term used for a developing foetus during the first two months of pregnancy is an embryo. After this time all of the major structures have been outlined, and it is called a foetus.

Pregnancy is divided into 3 periods of 3 months, called the first, second and third trimesters.

The birth of a child begins with labour, and normally the baby is delivered head first, through the cervix and vagina.