Clinical overview
Infant feeding is one of the highest-leverage conversations in the whole of antenatal and postnatal care, and in South Africa it sits at the intersection of nutrition, infection (HIV in particular), poverty, and powerful commercial pressure. The decisions made in the first hour and the first weeks of life shape childhood survival, growth, immunity, neurodevelopment, and the mother's own postpartum recovery. For the FCOG(SA) candidate the objective verb is discuss — meaning you must be able to lay out the options fairly, weigh their risks and benefits in a given clinical and social context, counsel a specific woman to an informed choice, and know the few situations where one option is medically mandated and the rest contraindicated.
The headline numbers frame the stakes. Globally and in South African policy, exclusive breastfeeding (EBF) for the first six months, followed by continued breastfeeding with appropriate complementary feeding to two years and beyond, is the recommended norm (WHO; SA NDoH). Breastfeeding reduces infant infectious morbidity and mortality (particularly diarrhoeal and respiratory disease), reduces sudden unexpected death, and confers maternal benefits. Yet South Africa has historically had low EBF rates, driven by a legacy of formula promotion, the HIV epidemic, and the practical realities of women returning to work and of mixed feeding. Your job is to be neither a dogmatist nor a defeatist: you support breastfeeding as the default, you make it work where you can, and you handle the genuine exceptions safely. This chapter assumes you have already framed the pregnancy through Antenatal booking and Pregnancy nutrition, and connects forward to Normal puerperium, Postpartum contraception and HIV in pregnancy.
Core knowledge
The four feeding options
There are, practically, four options to be able to describe and contrast:
| Option | What it is | Primary role |
|---|---|---|
| Exclusive breastfeeding (EBF) | Only breast milk (plus prescribed medicines/ORS), no water, other fluids or solids, for 6 months | The recommended default for almost all SA mother–infant pairs |
| Mixed feeding | Breast milk plus other milks/fluids/solids before 6 months | The riskiest pattern, especially with HIV — avoid |
| Exclusive formula (replacement) feeding | Commercial infant formula, no breast milk | For genuine contraindications, or informed maternal choice that meets safety criteria |
| Expressed breast milk / donor milk | Mother's own expressed milk or pasteurised donor human milk (PDHM) | Preterm/sick infants, separation, low supply support |
Physiology of lactation
Figure I19.1 — Lactation physiology: the prolactin synthesis pathway, oxytocin let-down, demand-led supply control and the top-up trap.
Milk production is governed by two hormones acting on a primed breast. Prolactin, released from the anterior pituitary in response to suckling, drives milk synthesis by the alveolar lactocytes. Oxytocin, from the posterior pituitary, causes myoepithelial contraction and milk ejection (the "let-down" reflex) and is conditionable, so stress and pain inhibit it. After delivery of the placenta, the fall in progesterone removes the brake on prolactin and triggers lactogenesis II (copious milk "coming in") at roughly day 2–4. Thereafter supply is governed by autocrine, demand-led control: frequent effective milk removal up-regulates production; retained milk (via the inhibitory peptide FIL — feedback inhibitor of lactation) down-regulates it. This is why early, frequent, unrestricted feeding with good attachment is the single most important determinant of supply, and why "topping up" with formula is self-defeating — it reduces stimulation and supply.
Colostrum, produced in the first few days, is low in volume but rich in immunoglobulin (secretory IgA), lactoferrin, leucocytes and growth factors — immunologically and developmentally ideal, and matched to the neonate's tiny gastric capacity. Mature milk is dynamic: foremilk is more watery and thirst-quenching; hindmilk is fattier and calorie-dense, which is why one breast should be finished before offering the second.
Why breast milk is biologically superior
- Anti-infective: secretory IgA, lactoferrin, lysozyme, oligosaccharides (prebiotic), live leucocytes and the maternal microbiome — directly lowering gastroenteritis, respiratory and middle-ear infection. This matters enormously where water and sanitation are unsafe.
- Nutritionally complete and adaptive to the term infant for the first 6 months (the one caveat being vitamin D and, in some settings, vitamin K at birth — standard teaching, hedge specifics).
- Gut and immune programming: promotes a healthy microbiome and gut closure.
- Maternal benefits: faster involution and reduced immediate postpartum bleeding (oxytocin), lactational amenorrhoea, and reduced longer-term risk of breast and ovarian cancer and type 2 diabetes (standard teaching).
- Practical and economic: free, sterile, always the right temperature, no preparation errors — decisive advantages in low-resource and emergency settings.