This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Obstetrics, Subject name: Gynaecology & Obstetrics
About Corpus luteum of pregnancy, all are true EXCEPT:- 
Select and explain. 
A. Stimulated by chorionic gonadotropin hormone, B. Persist till fouh month, C. Secretes progesterone, D. Main hormone secreted is estrogen
D: Main hormone secreted is estrogen
Answer: D: Main hormone secreted is estrogen 
Explanation: After ovulation ,wall of follicle collapses and is conveed to corpus luteum. The formation of corpus luteum is stimulated by the secretion of LH from anterior pituitary. Lutien cells secrete mainly the progesterone and small amount of oestrogen. In the absence of pregnancy, corpus luteum is called corpus luteum of menstruation and it persist for 12-14 days after ovulation If ovum is feilized and embedded in the endometrium of uterus, the trophoblast secrete chorionic gonadotropin hormone which stimulate the corpus luteum to grow and prolong its activity It is known as corpus luteum of pregnancy which continues to secrete progesterone upto the end of fouh month of pregnancy.