Clinical overview
The puerperium is the interval from delivery of the placenta until the maternal reproductive tract and physiology have returned, more or less, to the pre-pregnant state — classically taken as the six weeks after birth. It is a deceptively quiet phase. The drama of labour is over, the baby is out, and the temptation — for mother, family and tired staff alike — is to treat the woman as "delivered" and therefore safe. The data say otherwise. A substantial share of maternal deaths in South Africa occur after delivery rather than during labour, driven by postpartum haemorrhage, sepsis, hypertensive complications and venous thromboembolism, all of which present in a body that is rapidly re-modelling. The registrar's task in the normal puerperium is to know what ordinary physiology looks like so precisely that the abnormal announces itself.
This chapter describes the normal course — the involuting uterus, the lochia sequence, the establishment of lactation, the diuresis and the resolution of the pregnancy-state cardiovascular and haemostatic changes — and frames the routine observations and counselling that surround it. It is the physiological baseline against which Puerperal complications are read. Throughout, the South African framing is the National Integrated Maternal and Perinatal Care Guideline, 5th edition (2024), which structures postnatal care into the immediate, early and late puerperium and ties each phase to scheduled contacts.
Core knowledge
Defining and sub-dividing the puerperium
Standard teaching divides the puerperium into three overlapping phases, useful because risk clusters differently in each:
- Immediate — the first 24 hours, dominated by haemorrhage risk and cardiovascular re-adjustment.
- Early — up to roughly the first week, when involution is most rapid and sepsis and secondary haemorrhage emerge.
- Late (remote) — to six weeks, when lactation matures, fertility may return and contraception and mental-health needs come to the fore.
Uterine involution
After the third stage the uterus weighs about 1 kg; by six weeks it has returned to roughly 50–70 g (standard teaching). Involution proceeds by two mechanisms: myometrial contraction and retraction, which kinks and occludes the spiral arterioles (the "living ligatures") to secure haemostasis, and autolysis of the surplus muscle cytoplasm by intracellular proteolysis, so the number of myocytes changes little while each cell shrinks. Clinically the fundus is felt at about the umbilicus immediately after delivery and descends roughly one finger-breadth (≈1 cm) per day, becoming impalpable abdominally — behind the pubic symphysis — by about day 10–14 (standard teaching). Afterpains — cramping from these contractions — are worse in multiparas and during breastfeeding, because suckling triggers oxytocin release.
Lochia
The decidua sheds in a sequence whose colour and volume are a useful clinical clock:
- Lochia rubra — red, the first ~3–4 days, blood with decidual debris.
- Lochia serosa — pinkish-brown, to around day 10, serous with leucocytes.
- Lochia alba — yellow-white, for up to several weeks, predominantly leucocytes and cervical mucus (standard teaching on timing).
The trend should be of diminishing volume and lightening colour. A return to fresh red bleeding, an offensive odour, or passage of clots after the flow had settled all point away from normal involution and toward retained products or endometritis.
The cervix, vagina and pelvic floor
The cervix closes progressively: from an admitting hand at delivery, it usually admits only a fingertip by the end of the first week, though the external os characteristically remains a transverse slit thereafter (the parous os). The hypo-oestrogenic vaginal epithelium is thin and the rugae are lost early, recovering by about three weeks as ovarian function resumes (delayed by lactation). The pelvic floor and the introitus, stretched in labour, regain tone over weeks, aided by pelvic-floor exercises — relevant to later continence and to prolapse risk.
Endocrine and ovarian changes; return of fertility
Delivery of the placenta removes the dominant source of oestrogen, progesterone and human placental lactogen, whose levels fall sharply within days. The withdrawal of placental progesterone disinhibits prolactin's action on the breast and permits lactogenesis. In non-lactating women, ovulation may return from as early as about 4–6 weeks (standard teaching); in fully breastfeeding women, lactational amenorrhoea suppresses ovulation for longer but is never absolute. The practical message for Postpartum contraception is that the first ovulation precedes the first menstruation, so a woman can conceive before she ever sees a period.