A 31-year old patient who is compound heterozygous for the two galactose-1-phosphate uridyltransferase mutations p.Q188R and p.R333W delivered two healthy boys after uneventful spontaneous pregnancies. The patient chose to breast-feed her first baby and her galactose metabolites in blood and urine were monitored closely. A temporary increase in her galactose-1-phosphate (gal-1-P) levels with a maximum of 0.30 mmol/L on day 2 after delivery was observed. Galactose-1-phosphate was normalized 10 days after delivery. At the time of weaning, 8 months after delivery, her menses returned and she had normal sex steroid levels. She became pregnant again 2 months later. The second baby was also breast-fed. This time an increase in her gal-1-P values could be seen for 3 weeks with a maximum gal-1-P level of of 0.25 mmol/L at day 7. Only minor changes in her urine galactitol values were noted during the study period but the values stayed in the range of treated galactosaemia patients. We thus report that breast-feeding has been possible with only small adverse effects on the levels of galactose metabolites in a patient with classical galactosaemia.