Breastmilk is a wonderful thing. Not only does it feed your baby and provide him with the right amount of nutrients, but it also gives him or her protection against diseases. During the last three months of pregnancy, mothers start passing on antibodies to their child through the placenta, in a process called passive immunity. Antibodies, also called immunoglobulins, are proteins that the immune system develops to fight and destroy harmful invaders or antigens like disease-causing parasites, viruses, and bacteria, as well as cell changes such as those caused by cancer cells.