Placental protein 14 secretion during in vitro fertilization cycles with and without human chorionic gonadotropin for luteal support

To investigate levels of placental protein 14 (PP14) in in vitro fertilization (IVF) patients with and without exogenous human chorionic gonadotropin (hCG) for luteal support. Thirty-one women undergoing IVF were studied. For 18 women, hCG was administered in the luteal phase, and 12 became pregnant. Five pregnancies occurred in 13 women not receiving exogenous hCG. All the patients attended the University of Southampton/Chalybeate Hospital IVF program. There was no change in PP14 levels 2 days after embryo transfer (ET), but small significant rises were noted by day 8 in all patients. Thereafter, levels rose further in pregnant subjects but showed no change in nonpregnant patients. The highest level of PP14 was seen in the group of women on hCG support, but there was no overall statistical difference between those on support and those not. In the nonpregnant group, there was no significant correlation between progesterone (P) and PP14 8 days from ET, whereas a highly significant correlation was noted in the pregnant group. Neither hCG nor P are primary factors in the control of endometrial PP14 secretion, but PP14 and P may have common underlying control mechanisms.