Changes during puberty
There are many changes that occur to a female body during puberty, primarily because of the action of the hormones estrogen and progesterone.
A girl starts to:
- develop breasts
- her hips widen
- and her waist narrows due to the redistribution of fat under the direction of these hormones.
- Pubic, underarm and leg hair thicken and darken
- and you start to bleed from the vagina once a month
- On top of this, hair and skin may become oily, and you may experience cramps, mood swings, irritability and fatigue.
Amazingly, all these changes are preparing your body physically to be able to conceive and bear children. However, it can take a lot longer to be able to cope emotionally, mentally and spiritually with sexuality and having children.
Menstruation is the major biological process which facilitates reproduction. That is, when a girl starts to have a regular menstrual cycle it means that she is fertile and is able to have a baby.
On an emotional level having a regular menstrual cycle opens a young woman to her intuition and instincts, and the world of cycles. Nothing is ever straight down the line, or clear cut anymore.
A young woman becomes aware of the shades of grey. She may start to sense more vividly the hidden motives, thoughts and actions of others. She may start to sense a world beyond what she has experienced up until this time and that may be confusing. alternatively, if she was a particularly sensitive and intuitive child, she may find that these sometimes abandoned or lost skills may come to the fore again.
The biology of puberty and menstruation
At the onset of puberty a girls body is flooded with different hormones. The hormones cause the changes in your body and many of the unstable feelings that you may experience.
With all the changes, it is understandable if you don't quite feel like yourself or like you used to as a child.
The menstrual cycle is a delicate interplay of hormones and the cycle begins on the first day of bleeding.
At this time the pituitary gland releases a hormone called FSH (or Follicle Stimulating Hormone) which "targets" the ovaries.
The follicles are stimulated by the FSH to ripen several eggs in preparation for ovulation
At the same time another hormone called oestrogen is released by the ovaries, causing changes in the cervix, that is the neck of the womb, which softens and rises. Cervical mucus becomes more profuse and friendly to sperm and the womb lining or endometrium (which thickens and prepares for implantation).
All these changes ensure conditions are ripe within the reproductive system for fertilisation to occur.
When the levels of oestrogen reach a high enough level, this signals to the pituitary gland to release a sudden surge of the hormone 'LH' causing the release of the ripest egg from its follicle (imagine an egg exploding from its fleshy protective sac). This is ovulation. The ripe egg is collected by the nearest fallopian tube to await fertilisation.
This is the fertile time in a womans menstrual cycle. It is during these few days of ovulation that is is possible to get pregnant if you have unprotected sexual intercourse.
The burst follicle within the ovary that is left behind is now called the corpus luteum or 'yellow body'. The corpus luteum, which is in effect a tiny and temporary endocrine gland, continues to secrete reduced amounts of oestorgen which return the cervix (closes and hardens) and mucus (dries up) to their naturally infertile state.
The corpus lutuem also begins to secrete greater amounts of another hormone called progesterone causing the endometrium to thicken even more in absolute preparation for the egg (which is starting its journey down from the fallopian tube to the uterus).
It also signals the ovaries to stop releasing eggs and assists in returning the cervical mucus to its infertile state.
If the fertilised egg implants successfully into the womb lining, pregnancy occurs,
If fertilisation does not occur, the corpus luteum dies, ceasing the production of hormones. Therefore the uterine (womb) lining breaks down accompanied by blood. This is menstruation.
We have returned to day 1 when the whole process starts all over again.
Quick Glossary of terms.
Pituitary gland - is a gland located in the brain that regulates a wide range of bodily activities from growth to reproduction.
Targets - travels through the bloodstream and impacts upon.
Ovaries - female glands that produce hormones and the female reproductive egg or germ cell (ova).
Follicles - small secretory sacs or cavities which surround the ocum in the ovary.
Ovulation - the release of a fertile ocum or egg from the ovary into the fallopian tube.
Fertilisation - when the male sperm meets with the female egg or ova after sexual intercourse.
corpus luteum - or yellow body is in effect a tiny and temporary endocrine gland.
Written by Nadia MacLeod