The gestation period is the time it takes for a developing embryo or fetus to grow inside the womb until birth. This duration varies significantly among different species. For example, the gestation period for humans is about nine months, while for elephants, it can last up to 22 months. During this time, the fetus undergoes critical development, including the formation of organs and systems. Factors such as the species, health of the mother, and environmental conditions can influence the length of the gestation period. Understanding gestation is important in fields like veterinary medicine and reproductive biology.