Gestation period is defined as the time

The gestation period is the time between conception and parturition. Gestation is the period of pregnancy in mammals, during which a fertilized egg develops into a fetus and prepares for birth. The gestation period is the length of time from when the sperm fertilizes the egg to when the animal gives birth. This period can vary greatly among different species, ranging from a few weeks in some small mammals to over a year in elephants and whales. The time of fusion of the sperm and the egg is referred to as fertilization. The time of release of the ovum from the ovary is referred to as ovulation. The time of birth of the young animal is referred to as parturition.