The Female and male body is designed for procreation at the basic level. The physical differences between them cannot easily be distinguished until puberty. It is only after puberty that the sexes begin to develop their unique features. When puberty starts, both genders undergo physical and emotional changes in preparation for reproduction. These changes are controlled by series of hormones.
WHAT ARE HORMONES?
Hormones are chemical messengers produced by the endocrine glands and released into the bloodstream. Female hormone levels can change over time and most significant changes occur during puberty, at pregnancy, and menopause. These hormones include Estrogen, Progesterone, Gonadotropin Releasing hormone, Follicle stimulating hormones and Luteinizing hormone. The ovaries and adrenal glands are the main producers of these hormones.
Estrogen: Largely, estrogen production occurs in the ovaries but the adrenal glands and fat cells can also produce small amounts of this hormone. Estrogen is important in reproductive and sexual development such as breast development, fat distribution to thighs, hips and legs which all begins at puberty.
Progesterone: This hormone is produced by the ovaries, adrenal glands, and placenta. Progesterone levels increase during ovulation and peaks at pregnancy. Progesterone helps stabilize menstrual cycles and prepares the body for pregnancy.
Gonadotropin Releasing Hormone (GnRH): The development and maturation of egg in a menstrual cycle is stimulated by the release of gonadotropin releasing hormone by the brain. GnRH in turn stimulates the release of follicle stimulating hormone (FSH) and luteinizing hormone (LH) which regulate ovarian functions.
Follicle stimulating hormone (FSH) and luteinizing hormone (LH): In females, FSH stimulates growth and development of follicles in preparation for ovulation. The LH triggers ovulation and stimulates the secretion of progesterone in the body.
PUBERTY IN FEMALES
Puberty starts when the pituitary gland in the brain signals ovaries to start producing more estrogen. The body grows fast and starts to change into an adult body. Puberty usually starts between ages 8 to 13 in girls, although it may start earlier or later.
Breast and Hair growth in pubic area and armpits are usually the first signs of puberty. Changes in the body structure such as increase in size and shape, face and skin will also occur. Skin changes such as oily skin can cause acne or pimples which affects nearly every teenager and many young adults. Changes in hormones can cause body odor and since the skin glands are growing, sweating will increase. Other changes include increase in the vulva and vagina size, increase in the mucous produced in the vagina, and menstruation.
ROLES OF HORMONES IN MENSTRUATION
Menstruation is a monthly process in a woman in which blood and other materials are discharged from the lining of the uterus until menopause which is the ceasation of this of this menstrual discharge. Menstruation lasts for about 3-5 days. The female body goes through a number of changes in preparation for possible pregnancy. These events are called the menstrual cycle and during each cycle, an egg develops and is released from the ovaries. The lining of the uterus builds up and if pregnancy does not happen, the uterine lining sheds, then the cycle starts again. The cycle is divided into four phases; menstrual phase, follicular phase, ovulation phase and luteal phase.
Menstrual phase: This is the first stage of the menstrual cycle and the first day of bleeding. This phase starts when the egg from the previous cycle is unfertilized and no pregnancy occurred. As a result of this, the levels of estrogen and progesterone drop. The thickened lining of your uterus which would support a pregnancy is no longer needed, thus it sheds and comes out through the vagina as a combination of blood, mucus, and tissue from your uterus.
Follicular phase: The follicular phase starts on the first day of your period and with ovulation. The brain sends a signal to the pituitary gland to release follicle-stimulating hormone (FSH). This hormone helps to stimulate the ovaries to produce follicles which contain immature eggs. Only the dominant follicle will eventually mature. The rest of the follicles will be reabsorbed into the body. The maturing follicle causes a surge in estrogen that thickens the lining of your uterus in preparation for implantation.
Ovulation phase: Increased estrogen levels during the follicular phase triggers the pituitary gland to release the luteinizing hormone (LH). This is what starts the process of ovulation. Ovulation is when your ovary releases a mature egg. The egg travels down the fallopian tube toward the uterus to be fertilized by sperm. The ovulation phase is the most fertile period of the menstrual cycle and It occurs around day 14 of a 28-day cycle. After a day, the egg dissolves if it is not fertilized.
Luteal phase: After the follicle releases its egg, it changes into the corpus luteum and this releases hormones, mainly progesterone and some estrogen. The rise in hormones keeps the uterine lining thick and ready for a fertilized egg to implant. If pregnancy occurs, the body will produce human chorionic gonadotropin (hCG). It helps maintain the corpus luteum and keeps the uterine lining thick. If pregnancy does not occur, the corpus luteum will shrink away and be reabsorbed by the body. This will lead to decreased levels of estrogen and progesterone; thus, the uterine lining will shed during your period.
