Colostrum is the first milk produced by the mammary glands. The World Health Organization describes it as "the perfect food for newborns" . In humans, it is produced from about the fourth month of pregnancy. It's colour could be anything from clear fluid to yellow and provides all the nutrients a child needs the few days before breast milk comes in. It is also known to contain many immunoglobulins and antibodies that protect a baby from infections hence some people refer to it as "a baby's first vaccine " . Colostrum also has a laxative effect which helps newborns pass out that tar-like poo called 'meconium'.
Compared to more matured human breast milk, colostrum is said to have a higher protein content and lower sugar and fat contents; exactly as needed by newborns. Experts suggest that the breasts produce enough colostrum to nourish a newborn baby till the more mature breast milk comes in after a few days; they also suggest that babies be introduced to the breasts within the first hour of life which they say has several advantages including stimulating milk production. The more your baby suckles, the faster your milk comes in. This is because the activity of prolactin (the hormone which causes milk production) increases with frequent breastfeeding .
A newborn's stomach capacity is said to be about (5ml) one teaspoonful and thus easily satiated by colostrum; this capacity increases to above 30ml by the fifth day during which the mum's milk would have "come in". Colostrum gives way to the more mature breast milk after about 2-4 days post delivery It is therefore more important to frequently make newborns suckle the breasts than make each session last long. It is best to put the newborn to the breast at least 8-12 times everyday.