Objective: To analyze the factors affecting the variation of plasma concentration of placental protein 14 (PP14) in artificial cycles.
Design: The effects of different hormone replacement therapy (HRT) regimens were examined in a crossover design.
Setting: Jessop Hospital for Women, Sheffield, United Kingdom.
Patients: Eighteen women with premature ovarian failure: 6 associated with Turner's syndrome and 12 with idiopathic premature ovarian failure.
Interventions: Four different HRT regimens; 36 study cycles.
Main outcome measures: Plasma PP14 concentrations on days 1, 15, 19, and 29 of the artificial cycles.
Results: In cycles treated with a standard HRT, the levels were similar to those of the natural cycle. Subjects with Turner's syndrome did not have elevated PP14 levels, whereas the majority (9/12 [75%]) of those with idiopathic premature ovarian failure had elevated levels on day 29 of the cycle. Levels of PP14 were reduced when either the doses of estradiol valerate were reduced to 1/3 or the doses of progesterone (P) were reduced to 1/5 of the standard HRT.
Conclusions: Plasma levels of PP14 are dependent not only on P stimulation but also on adequate estrogen priming.