Growing Up

The Menstruation Cycle in Girls

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One or two years after budding, you may notice a blood stain in your underwear. This may mean that you are getting your first period. Each month, the lining of your uterus is built up with extra blood and tissue as the body prepares for pregnancy. When an egg is fertilized, it is anchored into the wall of the uterus and needs the extra blood and tissue to grow and stay protected. However, if the egg does not get fertilized, the extra lining is not needed anymore. Therefore, the extra tissue and blood on the wall lining of the uterus is shed and comes out through the vagina.

A period usually lasts from 5 to 7 days. Blood flow is usually heavier during the first day or two and becomes lighter towards the end of your period. The colour of the blood may also be bright or dark red in the beginning and turns brown towards the end.

Menstruation Cycle

Menstruation comes in a cycle, which can be anywhere from 21-35 days. In general menstruation cycle can be divided into different phases:

  1. Menstruation phase
    This phase marks the period when the lining of the uterus is shed.
  2. Follicular phase
    Follicular phase is a phase where follicles containing eggs start to develop in the ovaries. During this phase, the lining of the uterus will also start to repair and build up thicker. This is mainly due to the hormone oestrogen.
  3. Ovulatory phase
    Ovulatory phase marks the release of the eggs from one of the ovaries. It takes around 5 days for an egg to travel down into the uterus. This phase is also known as the fertile period. However, having your first menstruation does not necessarily mean that you are fertile. The first few menstrual cycles is not likely to result in successful ovulation. It may take up to a year for ovulation to regularly occur successfully.
  4. Luteal phase
    Luteal phase follows ovulation phase and is sometimes called secretory phase. When an egg is not fertilized, corpus luteum (the remnants of follicle after the egg is released) starts to break down. This will eventually lead to the shedding of the uterus lining and menstruation.

Sometimes, your menstruation may be accompanied with menstruation cramps just before or at the start of your period. This may be helped by over-the-counter pain medication and by holding a hot water bottle over the abdomen. Although rest may also relieve the pain, exercising can also reduce the cramps. Please see your doctor if the pain gets unbearable.