They are born alive not in eggs.
they are born alive not in eggs that means they come out of a stomach. The pig is a good example of how most mammals give birth and take care of the young pigs.
"From birth to 3-4 weeks of age, the piglets are with the sow (mother). For the first 3-4 weeks of life, the piglets consume milk from the sow. For the remainder of life, the primary components of pig diets are cereal grains, such as corn, and soybean meal. The soybean meal provides protein, while the cereal grains provide carbohydrates. The diet is supplemented with vitamins and minerals. The pig is a litter-bearing animal and a typical female will give birth to 10 or more piglets. It is common for sows to give birth to two litters of pigs each year. Thus, one female pig often produces 20 pigs each year."
taken from: http://www.ncagr.gov/cyber/kidswrld/general/barnyard/pigs.htm
"From birth to 3-4 weeks of age, the piglets are with the sow (mother). For the first 3-4 weeks of life, the piglets consume milk from the sow. For the remainder of life, the primary components of pig diets are cereal grains, such as corn, and soybean meal. The soybean meal provides protein, while the cereal grains provide carbohydrates. The diet is supplemented with vitamins and minerals. The pig is a litter-bearing animal and a typical female will give birth to 10 or more piglets. It is common for sows to give birth to two litters of pigs each year. Thus, one female pig often produces 20 pigs each year."
taken from: http://www.ncagr.gov/cyber/kidswrld/general/barnyard/pigs.htm