The World Health Organisation recommends exclusive breastfeeding up to 6 months of age, with continued breastfeeding along with complementary foods up to two years of age or beyond (11). Breast milk provides all the goodness your baby needs. It will give babies the best start in life, no matter where they live, their financial or social security.

Breast milk contains all baby’s essential nutrients baby in their most easily absorbed form. It also carries antibodies and stem cells, helping to transfer immunity to your baby (12).

There are very few circumstances that a mother may be unable or are advised not to breastfeed. If this is the case for you, or you choose not to breastfeed your baby, a human milk replacement formula will ensure baby gets the next best thing.

Human milk

Milk changes composition depending on factors including:

  • Whether the baby is preterm or full-term,
  • Whether it is a day or night feed,
  • If at the beginning, or the end of a feed,
  • How old your baby is.

Colostrum is the thick and sticky fluid that we produce for babies in the first couple of days after their birth. The breasts produce this clear-yellow fluid in small amounts – amounts which match the size of your baby’s stomach when he or she is born. Colostrum production is the first stage of a process called lactogenesis (lacto = milk-making), which usually begins during pregnancy.

Colostrum is very high in biological compounds – such as antibodies, stem cells and growth factors – and is vital in transferring immunity to your baby in their vulnerable first hours and days (12). If you choose not to breastfeed, please consider giving your baby colostrum in the early days of life. You can provide your baby with colostrum by first breastfeeding and then switching to formula, or by expressing and feeding baby with a cup, syringe or spoon. We cannot emphasise the value of colostrum enough.

Mature human milk is produced by lactogenesis (stage two) after the birth of your baby.

It contains:

  • 3%–5% fat,
  • 8%–0.9% protein,
  • 9%–7.2% carbohydrate (mostly lactose)
  • 30+ oligosaccharides (groups of simple sugars joined together)
  • 2% minerals (primarily sodium, potassium, calcium, magnesium, phosphorus and chlorine)
  • 60–75 kcal energy/100 ml

All the vitamins, except vitamin K, are found in human milk in nutritionally significant quantities. Protein content in mature milk is higher, and the carbohydrate content lower than colostrum. Colostrum has an oligosaccharide content 2.5 times higher than mature milk. Some of these sugars may function in establishing healthy gut flora in babies as they can promote the growth of certain strains of good bacteria (13).

Your breasts

As with any new skill or activity, it’s a good idea to get to know how the equipment works before you start using it. That way if it’s not working as we think it should we can troubleshoot and sometimes save ourselves a fair bit of stress. In the interest of stress-reduction, here is an overview of breast anatomy and how they work.

Before pregnancy, connective tissue, milk glands, and protective fat make up a large portion of the breast. The amount of fatty tissue varies from woman to woman. This feature accounts for the variation in breast size and shape. Hidden among the fat and glandular tissue are the milk ducts. This intricate network of channels grows in number and size during pregnancy due to the action of hormones. Oestrogen and progesterone are released in higher quantities as the placenta develops, stimulating the development of the milk-producing tissue and making milk production possible (14).

Milk ducts

  • Milk ducts branch off into smaller channels near the chest wall called ductules.
  • At the end of each ductule is a cluster of small, grapelike sacs called alveoli.
  • We call a cluster of alveoli a lobule;
  • A cluster of lobules is called a lobe.
  • Each breast contains between 15 and 20 lobes, with one milk duct for every lobe.
  • The milk ducts merge and end in about eight or nine holes in the tip of your nipple.

Your milk duct system fully develops during your second trimester. That way you can make milk for your baby even if he arrives early.

Milk production

While you are still pregnant, prolactin (the hormone that helps to produce milk), prompts the alveoli to remove nutrients from your blood supply to make breast milk.

  1. The network of cells surrounding the alveoli squeeze the glands and push the milk out into the ductules, which lead to a bigger duct.
  2. Once you birth your placenta, the estrogen and progesterone levels in your body suddenly drop.
  3. A rise in prolactin happens at this point, which acts on the alveoli and stimulates milk production.
  4. The nerves in the skin on your nipple are stimulated by the baby’s sucking, causing further prolactin to be released which stimulates new milk production.
  5. The hormone oxytocin triggers the ‘let-down’ reflex (where the breast releases or pushes out the milk it contains), and baby feeds.
  6. The more your baby breastfeeds, the more steps 5 and 6 continue in a feedback loop, and the more milk will be made (15).

Health benefits of breastfeeding

Breastfeeding has health benefits for both mothers and babies. Exclusive breastfeeding (around the clock on demand, non-expressing) provides natural (though not fail-safe) method of contraception (98% protection in the first six months after birth). It also reduces a woman’s risk of breast cancer, ovarian cancer, osteoporosis, type II diabetes, postpartum depression. It can help mothers to return to pre-pregnancy weight.

In addition to the health benefits already described, breastfeeding contributes to life-long good health. Breastfed babies are less likely to be overweight or obese in adolescence or as adults. They are also less likely to have eczema, asthma and type-II diabetes (11).

Practice, practice, practice

Although breastfeeding is a natural process, instinct can only take us so far. For first time mothers it a new skill to learn; with subsequent babies’ mums may have the skills they need. But this is not necessarily the case. While it would be ideal for all new mums to get the support they need to establish breastfeeding skills, not everyone is this lucky. For every baby, their first feed is their first time. If their mum has successfully breastfed before they are halfway to establishing a positive shared breastfeeding experience.

Establishing breastfeeding is the hard part. Once you and your baby are on your way, there isn’t much that can go wrong. Breastfeeding gets easier with practice, and before you know it, you will be feeding without thinking about it. Keep this in mind and persevere (14, 16).

Getting support with breastfeeding

If you are struggling, ask your midwife for support or a referral to a lactation consultant. They are uniquely qualified to offer you guidance with attaching your baby and ensuring he is feeding well. They can give you hints and tips to get the most out of breastfeeding. They will also be able to guide you toward breastfeeding supports available in your area.

If you are trying to establish breastfeeding, it’s a good idea to avoid giving baby a bottle in the first few days. Babies suck a bottle different from the breast and may get confused while he is still learning.

Is my baby getting enough milk?

It is common for mothers to worry whether their baby is getting enough milk, especially in the early days between colostrum and an established supply. Signs that your baby is getting enough milk are:

  • baby is feeding on demand
  • attaches well
  • changes rhythm while sucking,
  • pauses during the feed and starts again without prompting
  • comes off the breast when they are ready, looking full, satisfied and sleepy
  • has plenty of wet nappies.
full baby

If you are unsure whether your baby has had enough of a feed, wait until she stops on her own; then sit her up and gently rub her back to see if she burps. If she’s still looking alert and hungry, offer her the breast again. If she’s not, then she’s had enough.

Dirty nappies

Dirty nappies vary from baby to baby. It is not uncommon to find some babies that have a dirty nappy every feed, while others have one twice a week. What is important is that the number of dirty nappies is normal for your baby.

Dr Janelle McAlpine (PhD), Clinical Midwife
Image by Silbervogel, used under license from