Nursing 209

N209: Reproductive Health Study Guide o Contact with sex hormones, such as an estrogen or testosterone replacement therapy cream (used by parents) o Medical conditions, such as McCune-Albright syndrome or congenital adrenal hyperplasia, in which there is abnormal androgen production; hypothyroidism is thought to contribute in rare cases 1.2 Female Reproductive Development In the United States, the average age for menstruation to begin is age 12; however, it ranges from ages 8 to 15. It usually starts about two years after breast development begins. The menstrual cycle prepares the body for pregnancy each month; the average cycle is 28 days but ranges from 21-35 days in adults, and 21-45 days in young teens. Menstrual Cycle Phases Menstrual: This phase is from the onset of menses to the last day of bleeding. When no pregnancy occurs, the corpus luteum dies and progesterone levels fall, which causes the body to shed the uterine lining. This typically lasts 4-7 days. Proliferative (follicular): Follicles inside the ovaries develop and mature for ovulation. Levels of FSH increase, which stimulates the maturation of follicles that contain an ovum, or egg. The ovaries then produce estrogen, causing the uterine lining to thicken. When estrogen levels have peaked, FSH levels slow and the pituitary gland begins to secrete a luteinizing hormone, or LH. This causes the mature follicles to rupture and release the ovum that will then travel to the fallopian tubes. The release of the ovum is called ovulation, and occurs 14 days before the beginning of the next menstrual cycle. Secretory (luteal): After ovulation, LH causes the burst follicle to develop into the corpus luteum. When conception and implantation do not occur, the pituitary gland reduces the LH and FSH production, causing the corpus luteum to deteriorate, which then causes estrogen and progesterone to decrease. This triggers the shedding of the endometrium, causing the cycle to begin again. 1.3 Male Reproductive Development Puberty begins in the male between the ages of 9-15. When puberty begins, the pituitary gland secretes hormones that stimulate the testicles to produce testosterone, which brings about the physical changes of puberty. The stages of puberty can vary in timing, but generally follow a set sequence. During the first stage, the scrotum and testes grow larger. Next, the penis becomes longer and the seminal vessels and prostate gland grow. Hair begins to appear in the pubic area and later on the face and underarms. During this time, the voice deepens. Boys undergo a period of rapid growth during puberty as they reach their adult height and weight. A male who has reached puberty will produce millions of sperm each day. When the sperm complete their development, they travel to the

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