Recombinant human prolactin for the treatment of lactation insufficiency

Context Lactation insufficiency has many aetiologies including complete or relative prolactin deficiency. Exogenous prolactin may increase breast milk volume in this subset. We hypothesized that recombinant human prolactin (r-hPRL) would increase milk volume in mothers with prolactin deficiency and mothers of preterm infants with lactation insufficiency. Design Study 1: R-hPRL was administered in an open-label trial to mothers with prolactin deficiency. Study 2: R-hPRL was administered in a randomized, double-blind, placebo-controlled trial to mothers with lactation insufficiency that developed while pumping breast milk for their preterm infants. Patients Study 1: Mothers with prolactin deficiency (n = 5). Study 2: Mothers of premature infants exclusively pumping breast milk (n = 11). Design Study 1: R-hPRL (60 mu g/kg) was administered subcutaneously every 12 h for 28 days. Study 2: Mothers of preterm infants were randomized to receive r-hPRL (60 mu g/kg), placebo or r-hPRL alternating with placebo every 12 h for 7 days. Measurements Change in milk volume. Results Study 1: Peak prolactin (27.9 +/- 17.3 to 194.6 +/- 19.5 mu g/l; P < 0.003) and milk volume (3.4 +/- 1.6 to 66.1 +/- 8.3 ml/day; P < 0.001) increased with r-hPRL administration. Study 2: Peak prolactin increased in mothers treated with r-hPRL every 12 h (n = 3; 79.3 +/- 55.4 to 271.3 +/- 36.7 mu g/l; P < 0.05) and daily (101.4 +/- 61.5 vs 178.9 +/- 45.9 mu g/l; P < 0.04), but milk volume increased only in the group treated with r-hPRL every 12 h (53.5 +/- 48.5 to 235.0 +/- 135.7 ml/day; P < 0.02). Conclusion Twice daily r-hPRL increases milk volume in mothers with prolactin deficiency and in preterm mothers with lactation insufficiency.