The period a mammal is pregnant is commonly known as what period?

The period a mammal is pregnant is known as gestation. This refers specifically to the time from conception until the birth of the offspring, encompassing all stages of development within the uterus. During gestation, the fertilized egg develops into a fetus, where it undergoes significant growth and organ development necessary for survival outside the womb.

Nursing refers to the period after birth when the young mammal receives milk from its mother, which is crucial for nutrition and development but is not related to the pregnancy phase. Conception denotes the moment when the sperm fertilizes the egg, marking the beginning of pregnancy but not covering the entire duration. Fertilization is the biological process that results in conception, but similar to conception, it does not describe the full term of pregnancy. Thus, gestation is the accurate term that encompasses the entire pregnancy period for mammals.