THE MENSTRUAL CYCLE
What is the menstrual cycle (period)?
The menstrual cycle is the series of changes a woman's body goes through to prepare for a pregnancy every month. About once a month, the uterus grows a new lining (endometrium) to get ready for a fertilized egg. When there is no fertilized egg to start a pregnancy, the uterus sheds its lining. This is the monthly menstrual bleeding (also called menstrual period cycle) that women have from their early teen years until menopause, around age 50. The menstrual cycle is from Day 1 of bleeding to Day 1 of the next time of bleeding. The average cycle is 28-30 days. Girls usually start having menstrual periods between the ages of 11 and 14. Women usually start to have fewer periods between ages 39 and 51.
What controls the menstrual cycle?
Your hormones control your menstrual cycle. During each cycle, your brain's hypothalamus and pituitary gland send hormone signals back and forth with your ovaries. These signals get the ovaries and uterus ready for a pregnancy.
The hormones estrogen and progesterone play the biggest roles in how the uterus changes during each cycle.
- Estrogen builds up the lining of the uterus.
- Progesterone increases after an ovary release an egg (ovulation) at the middle of the cycle. This helps the estrogen keep the lining thick and ready for a fertilized egg.
- A drop in estrogen causes the lining to break down. This is when your period starts.
Did you know that the menstrual cycle has three phases?
1. The menstrual phase
2. The pre-ovulation phase
3. The post-ovulation phase.
Phase One - Menstrual Phase
During phase 1 period symptoms can include: Cramps, tender breasts, bloating, low mood, irritability, headaches, tiredness, low back pain etc.
Phase Two - Pre-Ovulatory Phase
During phase 2 the bloated feeling usually goes away. About half way through your cycle or two weeks before your period, the ovaries release the now mature ovum and ovulation occurs! You are usually feeling your best this week however, your energy may dip and you may experience mild cramps and breast tenderness etc.
Phase Three - Post-Ovulatory Phase
During phase 3 period symptoms can include: Bloating, tender breast, low mood, headache, weight gain, changes in libido, food cravings, trouble sleeping etc.