1. 4.Menstrual Cycle 1

2. The menstrual cycle is a monthly cycle of changes in the female reproductive system 2 It is the way the uterus changes before and after the egg cell is released

3. The average menstrual cycle is 28 days but may vary from 20 to 40 days 3 It includes the maturing of the egg cell and preparation of the uterus to receive a fertilized egg

4. Day 1 is the day external bleeding begins 4 This bleeding lasts an average of 5 to 7 days

5. The bleeding is the lining of the uterus being cleaned-out 5 By shedding and discharging the blood vessels not needed since the egg cell was not fertilized

6. A new egg begins maturing in the ovary from days 8 to 13 6 Then on day 14 ovulation begins

7. 7 Vocabulary: ovulation The release of an egg cell from the ovary

8. The egg cell will travel along an oviduct called the Fallopian Tube 8 This trip lasts about 3 days and is the time for pregnancy to occur

9. If sperm is available, the egg cell can be fertilized immediately upon release from the ovary 9 Or could take a few days before fertilization

10. The egg cell continues from the Fallopian Tube to the uterus 10 If the egg cell has been fertilized then it will embed into the lining of the uterus

11. If the egg cell is not fertilized then it will die 11 The lining of the uterus will begin to release from the uterus to begin the period again

12. Menstruation occurs when the girl’s reproductive organs mature 12 This occurs around the age of 9 to 16 and will last until about 45 to 55 years of age

13. Late in menstruation there will be a gradual reduction of ovulation 13 Which could only occur every 2 or 3 months at a time until it stops completely

14. Menopause is when the menstrual cycle becomes irregular and eventually stops 14 When menstruation stops, pregnancy can no longer occur