Hyperlactation Syndrome

Hyperlactation syndrome is excess milk production that exceeds the infant's needs, causing fast milk flow, infant choking and fussiness, and maternal breast fullness and recurrent blocked ducts. It results from an overactive milk supply, often from excessive pumping, feeding on a rigid schedule, feeding from both breasts at each feed, breast massage and use of herbal galactagogues. It matters because it causes infant feeding difficulty, poor weight gain in some infants, maternal pain and recurrent mastitis.

• Risk factors: previous oversupply, high prolactin, excessive pumping or expressing, herbal galactagogues (fenugreek), feeding from both breasts at each feed, domperidone use, large breast storage capacity, oral contraceptive withdrawal.
• Infant may gain weight well or poorly depending on how much low fat foremilk is taken.
• Settles with feeding changes in 3 to 7 days.

Women have constantly full, heavy breasts, milk leaking and spraying, repeated blocked ducts and mastitis, and a very strong let down with pain. Infants gulp, cough, choke, pull off the breast, arch, are fussy and gassy, and pass green frothy stools; some gain weight very fast and some poorly.

• Forceful milk spray, large volume of milk on expressing.
• Frequent wet nappies with explosive green stools in the infant.
• Differential diagnosis: normal strong let down, infant reflux, cow milk protein allergy, tongue tie, lactose overload, mastitis, blocked duct, galactorrhoea from hyperprolactinaemia, pituitary adenoma, hypothyroidism.
• Complications: recurrent blocked ducts, mastitis, breast abscess, infant poor weight gain or colic, early weaning, maternal pain and fatigue.

The diagnosis is clinical, with assessment of the infant's growth and feeding.

• History of milk volume, let down, pumping habits, herbal and drug use; observation of a full feed for choking, clicking and pulling off.
• Infant weight and growth chart, number of wet nappies (6 or more daily) and stool pattern; examination of the infant for tongue tie.
• Breast examination for blocked ducts and mastitis; temperature.
• Prolactin and thyroid stimulating hormone if there is galactorrhoea after weaning, or if milk persists beyond 6 months after stopping breastfeeding; pituitary imaging for very high prolactin.

The principle is to slow milk production gently while keeping the infant well fed and preventing blocked ducts.

• Supportive: stop pumping and expressing except for comfort; block feeding: feed from one breast only for a 3 to 4 hour block (2 hour blocks for severe oversupply), then switch breasts, with the other breast hand expressed only to comfort; lean back or lie down to feed to slow the flow; let the baby finish the first breast before offering the second; burp the baby; cold compresses after feeds; stop herbal galactagogues; avoid tight bras; keep the infant's growth monitored; reduce block feeding length gradually over 1 to 2 weeks.
• Pharmacological: paracetamol 1 g oral 6-hourly (maximum 4 g in 24 hours); ibuprofen 400 mg oral 8-hourly with food for 3 to 5 days for pain; flucloxacillin 500 mg oral 6-hourly for 10 days or clindamycin 300 mg oral 6-hourly for 10 days in penicillin allergy for associated mastitis; cabergoline is not used because it stops lactation.
• Procedures: none.
• Special groups: infants with poor weight gain, tongue tie or reflux have assessment and treatment of that problem and continue breastfeeding; breastfeeding is compatible with paracetamol, ibuprofen and the antibiotics used.
• Red flags: fever above 38.5 degrees Celsius, red wedge-shaped area, breast abscess, infant weight loss or fewer than 6 wet nappies daily, blood in infant stool, persistent galactorrhoea after weaning, headache or visual disturbance.
• Follow-up: review in 1 week with infant weight; review at 2 weeks; return to normal feeding when supply settles; prolactin and thyroid tests if galactorrhoea persists; review at 6 weeks.