Breastmilk is produced by the mammary gland (breasts) in women of reproductive age. Following hormonal changes during pregnancy, the body begins to prepare for the production of breastmilk. Following delivery, some important hormones contribute to this process. These include prolactin and oxytocin, among others.
Prolactin, which is produced by the pituitary gland, is the main hormone responsible for milk secretion. There is an increase in its production at night, therefore breastfeeding at night is encouraged as it stimulates the pituitary gland to secrete more prolactin leading to more breast milk production. Prolactin also suppresses activities of the ovaries, so breastfeeding delays the return of menstruation and fertility most especially when the child is exclusively breastfed.
Another important hormone is oxytocin secreted from the posterior pituitary gland. It is produced when a baby suckles and stimulates sensory nerves in nipples. Oxytocin is a milk ejecting hormone, it causes fine streams of milk flowing from nipples.
Breast Milk Composition: The nutritional composition of breast milk is unique, perfectly matching the needs of a fast growing baby. Breast milk passes through 3 different stages due to physiologic processes – Colostrum, Transitional milk, and finally Mature milk.
Colostrum
This is the first to be secreted, with the production beginning a few days before delivery and lasting for some days after delivery. In certain parts of the country, it is believed this first secretion should be discarded as it is a major cause of childhood diarrhoea. However, this is false, as the colostrum is quite beneficial to the newborn.
The colostrum contains large quantities of antibodies and growth hormones that are needed for the child’s development. It enhances the development of the baby’s gastro-intestinal tract. Its anti-infective agents act like the first immunization that confers some form of immunity for the infant.
Colostrum also has a laxative effect which helps the baby pass meconium, which is the first stool in a newborn. The protein content in colostrum is higher than mature milk. It contains more of some minerals and fat soluble vitamins A, E and K and has less carbohydrate and fat. Most importantly, it is highly nutritious.
Transitional milk
Shortly after the production of colostrum is the production of the transitional milk. The transitional milk is more in quantity and appearance but has less immunoglobulin and protein and more fat and carbohydrate (sugar) content when compared to colostrum.
Mature milk
Mature milk comes during the next 1-2 weeks after transitional milk, It consists of foremilk and hind milk. Fore-milk comes at the beginning of a feed, looks grey and watery, rich in protein, lactose, vitamins and minerals and water. As baby feeds on, the milk changes to hind-milk.
Hind-milk comes at the end of a feed. It looks whiter than fore-milk because it contains more fat. Fat content continues to increase from beginning to the end of feeding. Fat supplies more than half the energy in breast milk. Foremilk quenches baby’s thirst while foremilk gives satiety because as foremilk decreases in water, hind milk increases in fat. Babies need both fore milk and hind milk for growth and development. It is important not to take a slow feeding baby off the breast before he finishes or he may not get enough hind milk.
BREAST MILK IS THEREFORE A PERFECT FOOD that contains all the nutrients a baby needs for the first 6months of life. It is quickly and easily digested, it contains the most suitable protein and fat in right quantities. It contains the correct amounts of salt, calcium and phosphate. It has lactose needed for brain development and a special enzyme – lipase – which digests fat. It contains enough vitamins, iron and other nutrients that a growing baby needs. We should take note that breastfed babies do not develop iron deficiency anaemia and breast milk contains 70% water, enough for a baby, even in a hot, dry climate.
Breastfeeding and Immunity
Breast milk is clean, free of bacteria and contains anti-infective factors which prevent infections, so it cannot make a baby sick. Some of these anti-infective factors include; live white blood cells (leucocytes) which kill bacteria, anti-bodies (immunoglobulins) to many common infections until the baby can make his own antibodies, lactoferrin which binds iron preventing the growth of some harmful bacteria which needs iron and a substance called “bifidus factor” which helps special bacteria called Lactobacillus bifidus to grow rather than harmful bacteria that cause diarrhoea.
Breast milk continues to help prevent illness and to help children recover during second and third years of life because as lactation winds down, breasts involute, regression milk (resembles colostrum in its high level of immunoglobulin as it prevents weaning diarrhoea).
Breastfed babies are protected against infections with less diarrhoea, fewer respiratory and middle ear infections and a baby who continues to breastfeed during infections recovers faster than a baby who stops breastfeeding.
Other Benefits of Breastfeeding
Breastfeeding helps mother and baby develop a close love bond. This relationship may help the child form good relationships with other people. A baby that is bottle fed gets less affection and stimulation. Frequent breastfeeding helps protect against unwanted pregnancy due to release of prolactin from the posterior pituitary gland and helps mother regain her normal figure.
Also, breastfeeding ensures that a baby is receiving perfect food for its age, protects baby from indigestion that artificially fed baby suffers from, protects baby from persistent diarrhoea caused by contaminated milk, protects baby from anaemia because the iron content of breast milk is well absorbed, protects baby from allergies like asthma, eczema from bottle feeding and encourages the birth weight of baby to double by the age of 5months. Finally, it is an ever available economical way of feeding a baby.
Breastfeeding in special situations
• Twins – some mothers feed both twins at the same time. Some feed one first and then the other. Sometimes each twin feeds from one breast, other times they interchange breasts.
• Low birth weight – preterm milk contains more protein than mature milk. Preterm babies need extra protein and they grow better on their mother’s preterm milk than on donated mature milk. Mothers should express their milk. Babies who weigh less than 1.600g are fed by a feeding tube. If a baby weighs 1.600g and can swallow, the mother can feed from a cup which is safer than tube.
• Cleft lip or palate – some babies need to be fed expressed breast milk (EBM) by tube or with a cup until the baby can suckle.
• Babies with Jaundice should be given colostrum, as colostrum helps to clear meconium and prevent jaundice.
About Author:
KUMCHI JENNIFER L. is a final year medical student from the University of Jos; active in the Jos University Medical Students’ Association (JUMSA) as the Special Adviser (S.A) to the President on travels and conferences, and S.A to the North Central Coordinator on political matters.
