After fertilization the embryo implants in the endometrium and begins secreting a hormone called chorionic gonadotropin (CG), which can be detected in the mother's blood and urine shortly after implantation. CG functions to prevent the corpus luteum from degenerating so that it may continue to produce estrogen and progesterone, which is essential to the maintenance of pregnancy. Using this information, suggest a way we could determine, without invasive methods and without visiting the doctor, whether someone is pregnant or not.
choose one:
Look for a means to determine presence or absence of the corpus luteum.
Develop a test to detect CG in the mother's urine.
Develop a test to detect CG in the blood.
Use ultrasound to determine implantation of the egg.