Estradiol for tissue of the reproductive organs, supporting the lining of the vagina, the cervical glands, the endometrium, and the lining of the fallopian tubes. It enhances growth of the myometrium. Estradiol appears necessary to maintain oocytes in the ovary. During the menstrual cycle, estradiol produced by the growing follicles triggers, via a positive feedback system, the hypothalamic-pituitary events that lead to the luteinizing hormone surge, inducing ovulation. In the luteal phase, estradiol, in conjunction with progesterone, prepares the endometrium for implantation. During pregnancy, estradiol increases due to placental production. The effect of estradiol, together with estrone and estriol, in pregnancy
Menstrual synchrony Israel. Twenty seven families, which had from two to seven sisters 13 years or older and collected data on menstrual cycle onsets over a three-month period. Using the methods of, they reported menstrual synchrony occurred for the first two months, but not for the third month for roommate sisters, close friend roommates, and for families as a whole. Strassmann investigated whether menstrual synchrony occurred in a natural fertility population of Dogon village women. Her study consisted of 122 Dogon women with an average lifetime fertility rate of 8.6 ± .3 live births per woman. Their median cycle length was 30