Breastfeeding
Breastfeeding is driven by prolactin-mediated milk production and oxytocin-mediated let-down, and its clinically important complication is lactational mastitis, treated with dicloxacillin or cephalexin 500 mg PO four times daily for 10 to 14 days while breastfeeding continues, alongside engorgement, nipple injury, plugged ducts, and galactocele.
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What this article covers
- Overview
Prolactin drives milk production and oxytocin drives milk ejection: after delivery of the placenta, estrogen and progesterone fall sharply, releasing prolactin's stimulation of alveolar epithelial…
- Epidemiology
Lactational mastitis is the most common breastfeeding complication requiring treatment, arising from cellulitis of the periglandular tissue when bacteria, usually Staphylococcus aureus, enter the…
- Risk factors
Nipple trauma, cracking, or fissuring from poor latch or infant positioning is the principal portal of entry for bacteria causing mastitis and is also the direct cause of nipple injury itself.
- Pathophysiology
Mastitis begins with a portal of entry: cracked or fissured nipple skin from breastfeeding trauma allows Staphylococcus aureus (occasionally Streptococcus) to enter the lactiferous ducts and…
- Clinical features
Unilateral breast tenderness with erythema, edema, and warmth is the hallmark of mastitis; purulent nipple drainage may be present.
- Differential diagnosis
Breast engorgement: bilateral firmness and tenderness without fever, erythema, or a focal mass; the key discriminator from mastitis is the absence of fever and focal findings.
- Diagnosis
Mastitis is a clinical diagnosis established by focal unilateral breast tenderness, erythema, edema, and warmth, distinguished from simple breast engorgement by the presence of focal symptoms, an…
- Management
First, for engorgement or a plugged duct without fever, manage conservatively: frequent breastfeeding or pumping to empty the breast, warm compresses before feeds and cold compresses between feeds…
- Complications
Breast abscess is the most serious complication of untreated or inadequately drained mastitis, requiring incision and drainage or aspiration in addition to antibiotics.
- Prognosis
Mastitis resolves with appropriate oral antibiotics in the great majority of cases within the treatment course, with most patients showing clinical improvement within 48 to 72 hours.
- Prevention
Ensure a proper latch and infant positioning from the first feeds, using lactation counseling, to prevent the nipple trauma that is the primary portal of entry for mastitis-causing bacteria.
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