Placental protein 14 concentrations in circulation related to hormonal parameters and reproductive outcome in women undergoing IVF/ICSI

Abstract

Serum concentrations of placental protein 14 (PP14), steroids and gonadotrophins were related to the outcome of IVF/intracytoplasmic sperm injection in 195 normogonadotrophic women subjected to the long protocol gonadotrophin-releasing hormone agonist (GnRHa; buserelin) pituitary down-regulation protocol and gonadotrophin stimulation (HMG or rFSH). Pituitary down-regulation was initiated on cycle day 21 and the patients were randomized to either intranasal or s.c. administration of buserelin. After 14 days of down-regulation, the patients were randomized on stimulation day 1 (S1) to ovarian stimulation with 225 IU per day of either human menopausal gonadotrophin (HMG) or recombinant FSH (rFSH) for a fixed period of 7 days. The daily gonadotrophin dose was adjusted on the following day according to ovarian response. Patient's blood was sampled for PP14 and hormone analysis on cycle days 21, S1, S8 and on the day of oocyte retrieval. Mean concentrations of PP14 on day 21 of the cycle were significantly lower in conception than in non-conception cycles, whereas progesterone and oestradiol were similar in conception and non-conception cycles. PP14 concentrations on the first day of stimulation and at oocyte retrieval were significantly higher in conception than in non-conception cycles, whereas concentrations after 8 days of stimulation were similar. Neither mode of GnRHa administration nor type of gonadotrophin significantly influenced PP14 concentrations throughout ovarian stimulation. Circulating PP14 is thus an important physiological signal of the fertility status of the individual in the cycle antecedent to and during ovarian stimulation. Measuring mid-luteal serum PP14 may offer a clinical test helping to decide if infertility treatment should be initiated in the subsequent cycle.