Heterogeneous distribution of serum prolactin values in apparently healthy young women, and the effects of oral contraceptive medication

Fertil Steril. 1987 May;47(5):785-91.


Controversy over effects of oral contraceptives (OCs) on serum prolactin (PRL) levels from retrospective studies suggested performing a prospective study. Statistical analyses of PRL levels in 552 reproductive-age, nonmedicated women indicated a provisionally lognormal distribution of values less than 15 ng/ml, contaminated by a small number of abnormally high values less than or equal to 90 mg/ml. Truncated samples were used to estimate a "normal range" of PRL levels for three subsets of the study sample, classified according to number of weeks after pregnancy. Fifty-microgram estrogen-containing OCs doubled basal PRL levels at 5 to 8 weeks in those whose initial control values fell below 15 ng/ml, but the PRL elevation was no longer evident at 6 months of drug use. These OCs induced a small but significant lowering of PRL at 5 to 8 weeks in those with control levels of 15 ng/ml or higher. Thirty-five-microgram estrogen-containing OCs failed to alter PRL levels at 5 to 8 weeks in those with control values less than 15 ng/ml.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Age Factors
  • Contraceptives, Oral*
  • Contraceptives, Oral, Hormonal
  • Estrogens
  • Female
  • Humans
  • Parity
  • Postpartum Period / blood
  • Pregnancy
  • Prolactin / blood*
  • Prospective Studies
  • Reference Values


  • Contraceptives, Oral
  • Contraceptives, Oral, Hormonal
  • Estrogens
  • Prolactin