Immunocontraception outcome has focused on human chorionic gonadotropin (hCG). hCG is not necessary for fertilization, but is secreted by embryos shortly thereafter. Therefore, immunity against hCG does not prevent fertilization. However, it was found that anti-hCG antibodies prevent marmoset embryos from implanting in the endometrium of their mother's uterus. The main function of hCG is to sustain the ovarian corpus luteum during pregnancy past the time it would normally decay as part of the regular menstrual cycle. For the first 7–9 weeks in humans, the corpus luteum secretes the progesterone necessary to maintain the viability of the endometrium for pregnancy. Therefore,
Half the Sky and when seen by patriarchal husbands and affected wives can change household dynamics. Another solution is sponsored by Always, Always provides feminine care products to school girls so that they do not miss school during their menstrual cycle, which often happens because they feel ashamed. The final and probably most empowering solution is an education. Allowing girls to attend school and go beyond elementary school can truly help women advance in developing countries. Carolyn See, a book critic from "The Washington Post", said in her review: "'Half the Sky' is a call to arms, a call for help, a call