CONCENTRATIONS OF PLACENTAL LACTOGEN IN CHRONICALLY CATHETERIZED EWES AND FETUSES IN LATE PREGNANCY

Abstract

SUMMARY: The concentration of ovine placental lactogen (oPL) was measured by radioimmunoassay in plasma samples from chronically catheterized ewes and their fetuses from day 110 of gestation to term (about day 145). Concentrations of oPL in the plasma of the mother and fetus were raised after surgery, and remained raised for 3–5 days after the operation. Concentrations of oPL were greatest in the fetus at days 120–124 of gestation, and then declined until delivery. Mean concentrations of oPL in the fetus in late pregnancy for single, twin and triplet pregnancies were 101±6 (s.e.m.), 100±11 and 117±59 ng/ml respectively and were not significantly different. Mean concentrations of oPL in the mother in late pregnancy for single, twin and triplet pregnancies were 718±227, 1387±160 and 1510±459 ng/ml respectively; the difference between these means was significant (P P r = 0·624, P <0·01).