An adult female or mother pig is called a sow. If the pig is a virgin or has not given birth, she is called a gilt. A gilt is usually less than a year old.
A young female pig is reproductively mature around the age of eight months. Sows typically give birth to eight or nine piglets with each litter, with some litters having as many as 12 piglets. If there are more piglets born in a litter, they are usually smaller. Once the piglets are born, the mother and babies are separated into their own stalls to prevent the sow from accidentally lying on or rolling over one of her piglets.