- Monthly changes in uterus to prepare it to receive a fertilised ovum
- controlled by the female hormones oestrogen and progesterone
- Menstruation begins the menstrual cycle
- discharge of blood and uterine tissue via vagina
- Average length is 28 days
- Can vary between 21 to 35 days naturally
- Luteal phase is constant (14 days)
- Affected by:
- Stress
- Illness
- Unbalanced diet
- Malnutrition
- Pregnancy pauses the menstrual cycle
- Yong women that live together tend to menstruate at the same time of the month
Fertile period
- Days just before and after ovulation when a female is able to get pregnant
- -3 +2 from ovulation day
Female Sex Hormones
| Hormones | Oestrogen | Progesterone |
|---|---|---|
| Role | Repairs/thickens uterine lining | Maintains uterine lining |
- Follicle Stimulating Hormone
- Stimulates follicles in ovaries to:
- Secrete oestrogen
- Develop and mature
- Eventually one matures into a Graafian follicle and others degenerate.
- Stimulates follicles in ovaries to:
- Lutenizing Hormone
- Stimulates ovulation
- Graafian follicle erupts (causes a fall in oestrogen level) to release and becomes the corpus luteum which secretes both progesterone and oestrogen
