Ahmed A G, Klopper A
Clin Endocrinol (Oxf). 1985 Dec;23(6):677-81. doi: 10.1111/j.1365-2265.1985.tb01128.x.
Daily measurements of serum oestradiol, progesterone, Schwangerschaftsprotein 1 (SP1) and hCG were made in 13 menstrual cycles during which conception occurred. The assays were continued until 21 d after ovulation. SP1 was detected in maternal blood 8-14 d after ovulation and hCG 9-13 d after ovulation. We conclude that these two proteins are secreted simultaneously but independently by the syncytiotrophoblast.
在13个受孕的月经周期中，每日测定血清雌二醇、孕酮、妊娠特异性β1糖蛋白（SP1）和人绒毛膜促性腺激素（hCG）。检测持续至排卵后21天。排卵后8 - 14天在母血中检测到SP1，排卵后9 - 13天检测到hCG。我们得出结论，这两种蛋白由合体滋养层同时但独立分泌。
