File:Pregnancy test.gif

Pregnancy test available to the public.

Based upon the detection of human chorionic gonadotrophin - (hCG) Placental hormone initially secreted by cells (syncitiotrophoblasts) from the implanting conceptus during week two, supporting the ovarian corpus luteum, which in turn supports the endometrial lining and therefore maintains pregnancy. Hormone can be detected in maternal blood and urine and is teh basis of many pregnancy tests. Hormone also stimulates the onset of fetal gonadal steroidogenesis, high levels are teratogenic to fetal gonadal tissues.

http://embryology.med.unsw.edu.au/Medicine/Flab08Embryo_1.htm