VARIATIONS IN CONCENTRATIONS OF THE MAJOR ENDOMETRIAL SECRETORY PROTEINS (PLACENTAL PROTEIN 14 AND INSULIN-LIKE GROWTH-FACTOR BINDING PROTEIN-1) IN ASSISTED CONCEPTION REGIMES

We have previously shown that placental protein 14 (PP14) concentrations were depressed in two pregnancies that followed down-regulation of the anterior pituitary and exogenous hormone support prior to a frozen-thawed embryo transfer, We now report on a more comprehensive series of pregnancies following this form of treatment, in-vitro fertilization (IVF) and natural cycle frozen-thawed embryo transfer, Serum specimens were analysed for PP14 and insulin-like growth factor binding protein-1 12 days after embryo transfer and at 7 weeks gestation, At 12 days after embryo transfer, the mean serum PP14 concentrations in the IVF and natural cycle were significantly higher in those who conceived than those who did not (82 versus 23 and 107 versus 39 mu g/l respectively, P < 0.001), Although the mean PP14 concentration in the hormone-supported pregnant patients was higher than in the non-pregnant patients, this had not reached statistical significance 12 days after embryo transfer (49 versus 31 mu g/l). By 7 weeks gestation the PP14 concentrations in the hormone-supported pregnant patients were significantly higher than in the non-pregnant patients (152 versus 31 mu g/l, P < 0.001), However, the PP14 concentrations for hormone-supported pregnant patients were significantly lower (P < 0.001) than those for pregnant IVF or natural cycle patients at 7 weeks gestation (152, 777 and 660 mu g/l respectively), The PP14 concentrations in the pregnant patients, although lower than those in IVF and natural cycle pregnancies, were higher than those previously reported in ovarian failure and Turner's syndrome ovum donation cycles, Patients treated by down-regulation and exogenous hormones had significantly higher serum IGFBP-1 concentrations than IVF and natural cycle patients at 7 weeks gestation (P less than or equal to 0.01); mean concentrations 107, 58 and 43 mu g/l respectively), Elevated IGFBP-1 concentrations may influence the rise in PP14 concentrations in these patients.