Serum prolactin levels during pregnancy, intrapartum and postpartum periods in Malay women

Serum human prolactin (hPRL) levels in Malay women during pregnancy, intrapartum and immediately postpartum have been invest£gated by means of a double-antibody radioimmunoassay technique. There was a progressioe rise of serum prolactin concentration from 31.9 ± 10.4 ng/ml in the first trimester to 242.0 ± 24.6 ng/ml at 36 weeks pregnancy unth. the mean values during the second and third trimester of 118.9 ± 12.7 ng/ml and 214.7 ± 10.3 ng/ml respectively. During intrapartum the concentration of hPRL was 191.9 ± 26.9 ng/ml and ithat of immediately postpartum was 178.3 ± 14.5 ng/ml. Suckling of the breast within 6 hours postpartum has resulted in a minor elevation of prolactin level, and this could have been due to the greater basal prolactin level, and/or the ineffectiveness of suckling as a potent stimulus during this period.