Onset of Menstruation (Menarche)
Most girls start menstruating between the ages of 11 and 13. However, environmental, nutritional, genetic. and even geographical factors can influence a girl’s “menarche.” It is not uncommon for a girl to begin menstruating as late as age 16 in areas where food is scarce and malnutrition is widespread. Alternately, girls who experience menarche at age nine or 10 should have a physical examination to rule out possible medical conditions.
Puberty in both boys and girls begins when the hypothalamus releases gonadotropin, a hormone that stimulates the production of testosterone in boys and estrogen in girls. The hypothalamus also signals the pituitary gland to start releasing follicle-stimulating hormone (FSH) if an egg has not been fertilized by sperm and no pregnancy exists. Shedding of the uterine lining (tissue, mucus, and blood) that would normally support pregnancy is called menstruation. Most women menstruate for three to seven days. Cramps, bloating, fatigue and headache are caused by rising and falling hormone levels and loss of blood.
Two Reproductive Cycles – The Uterine and the Ovarian
To prepare for a possible pregnancy, the uterine endometrial lining thickens as estrogen levels increase between menstrual cycles. Egg follicles will start developing, with one follicle ultimately maturing into an egg. Ovulation marks the time when the ovary releases a single egg. Following ovulation, the uterus enters the ovarian cycle in preparation for receiving a fertilized egg. Progesterone nourishes the uterus by promoting the growth of new blood vessels necessary for sustaining a fetus.
If implantation of a fertilized egg occurs, the embryo produces and releases human chorionic gonadotropin (HCG). The hormone HCG supports the corpus luteum, a temporary structure formed at the follicle site that releases the egg during ovulation. The corpus luteum also produces progesterone until a placenta develops. If pregnancy happens, the placenta takes over progesterone production and the corpus luteum becomes a scar tissue mass called the corpus albicans.
When pregnancy does not occur during ovulation, progesterone levels decrease rapidly, causing the uterine lining to dissolve and slough off as menstruation. The first day of a woman’s menstrual cycle marks the lowest point of the month for estrogen activity and the beginning of a new reproductive cycle.
How Does a Woman Know She is Ovulating?
For women who are having difficulty becoming pregnant, predicting when they are ovulating is important for determining when to have intercourse, undergo artificial insemination, or an in vitro fertilization procedure. Two primary signs that you may be ovulating involve a slightly higher than normal body temperature and thinning of cervical mucus. Secondary ovulation signs include light spotting, minor cramping on either side of your pelvis, bloating, and breast tenderness. Not all women experience secondary symptoms of ovulation.
The End of the Reproductive Cycle – Perimenopause and Menopause
Perimenopause marks a major transitory stage in a woman’s life when the ovaries start reducing their production of estrogen and reproductive organs gradually begin shutting down. Women can experience perimenopause signs in their middle to late 30s, but most report shorter, more irregular menstrual cycles during their early to middle 40s. When a woman does not have a period for 12 consecutive months, they are clinically considered to have reached menopause.
Viera Fertility Clinic Can Help Overcome Fertility Problems
Getting pregnancy is not always as easy as it seems. Slight hormonal imbalances, blocked fallopian tubes, polycystic ovarian syndrome, and minor uterine abnormalities can make it difficult for a reproductive-age woman to become pregnant. If you have tried to get pregnant for at least six months without success, contact us today to schedule a consultation appointment with fertility specialist Dr. Chamoun.