1. Ovaries and the Fertility Cycle
By: Louise, Sarah, and Rebecca

2. OVARY STRUCTURE
Located on either side of the uterus, below the opening of the fallopian tubes
Within are small groups of cells called follicles
Follicles are made up of two types of cells
Primary Oocyte Cells: they contain the genetic makeup and undergo meiosis to be transformed into a mature oocyte
Granulosa Cells: they provide nutrients to the oocyte

3. OVARY STRUCTURE
At puberty, each ovary contains about 400,000 follicles
Many follicles develop during each fertility cycle, but only a single follicle reaches full maturity
The other follicles deteriorate and develop into the corpus luteum, a yellow endocrine tissue that forms in the ruptured follicle
Releases hormones necessary during pregnancy
If pregnancy does not occur, the corpus luteum will disintergrate after ten days

4. THE OVARIES

5. OVARY FUNCTION Produces egg cells Produces estrogen and progesterone
Estrogen is secreted to thicken the walls of the uterus, and it also activates the development of other female sex characteristics
Progesterone maintains the uterine lining during pregnancy

6. STOP THE FLOW

7. THE FERTILITY CYCLE
The Ovarian cycle occurs at the same time as the menstrual cycle - each cycle lasts about 28 days
Menstrual cycle means the changes that occur in the uterus
Ovarian cycle is the changes that occur in the ovaries

8. PHASE ONE… FLOW PHASE Days 1 - 5
Only phase that can be determined externally
The uterus lining (endometrium) is broken down and excreted out the vagina
Continues until the endometrium is completely excreted

9. PHASE TWO... THE FOLLICULAR PHASE
Days
The follicles in the ovaries begin to develop
The egg cell enlarges and becomes multi-layered
One of the follicles goes on to enlarge and mature whiles the others disintegrate

10. HORMONES DURING THE FOLLICULAR PHASE
GnRH (Gonadotropin - releasing hormone) is released from the hypothalamus and stimulates the pituitary gland to secrete FSH (Follicle Stimulating Hormone)
The release of FSH stimulates the follicle development
The follicles then secrete estrogen, which stimulates endometrium production

11. The outer surface of the ovary wall bursts and the egg is released
OVULATION OCCURS
The outer surface of the ovary wall bursts and the egg is released

12. PHASE THREE... OVULATORY PHASE
FYI: The uterus always prepares for possible pregnancy before ovulation
The rising estrogen levels during phase two causes increased LH secretion, which results in ovulation
The ovary ruptures and the egg is released
The follicle remains in the ovary and it develops into the corpus luteum

13. PHASE FOUR... LUTEAL PHASE
Days
The Corpus Luteum secretes estrogen and progesterone
Prepares the uterus for a fertilized egg by gradually building up the endometrium lining (also known as the poliferative phase)
The cycle starts over with the flow phase unless the woman becomes pregnant

14. HORMONES DURING THE LUTEAL PHASE
After ovulation, the high levels of LH stimulate the follicular tissue to develop a corpus luteum which then secretes estrogen and progesterone
These hormones stimulate endometrium production by supplying blood to the uterine lining
When LH levels become too low, the corpus luteum disintergrates
When the woman is not pregnant, estrogen and progesterone levels drop, which then restarts the flow phase (causes endometrium lining to shed)

15. THE MENSTRUAL CYCLE

16. EVENTS OF THE FERTILITY CYCLE
Information and Quiz:
Video:

17. HOMEOSTATIC REGULATION OF THE FERTILITY CYCLE
The Hypothalamus-Pituitary Complex regulates the hormones of the ovaries
When female puberty occurs, the gonadotropin-releasing hormone (GnRH) is released from the hypothalamus
This stimulates the pituitary gland - the storage site for the gonadotropins LH (luteinizing hormone) and FSH (follicle - stimulating hormone)
A negative feedback loop is then developed to regulate both the gonadotropins and the ovarian hormones during the fertility cycle

18. NEGATIVE FEEDBACK LOOP

19. POLY-CYSTIC OVARIAN SYNDROME
What is PCOS?
How common is it?
What causes it?
Symptoms?
Treatment?

20. WHAT IS PCOS?
Ovaries are larger than normal, and follicles appear in clumps. (May not affect fertility)
Cysts cause a hormonal imbalance and symptoms develop, which makes it a syndrome.
PCOS = Women who have Polycystic Ovaries with symptoms
“Metabolic" disorder (many factors cause this)

21. HOW COMMON IS IT?
Most common hormonal disorder occurring in women during their reproductive years
4% to 10% of all women have the disorder
Many women don’t know that they have PCOS so the number is probably higher than 10% (Mis- diagnosis)
Symptoms start to show shortly after puberty

22. CAUSES Combination of 2 or more of these factors: Genetics
Insulin resistance or hyperinsulinism (high blood levels of insulin)
Obesity
Hyperandrogenism (excessive production of male hormones)
Abnormality of the hypothalamic-pituitary-gonadal axis (organ/hormonal disorder)
Environmental chemical pollution (hormonal disruptors)
Food adulterantion (excitatory amino acids, for example)
Chronic inflammation

23. SYMPTOMS Multiple ovarian cysts Irregular or absences of menstruation
Obesity/inability to lose weight
Infertility
High blood pressure
Excessive body or facial hair
Polycystic ovaries that are 2-5 times larger than healthy ovaries
Multiple hormone imbalances (estrogen levels, insulin, thyroid hormones)

24. TREATMENT OPTIONS Birth control pills
Metformin (Glucophage) - increases insulin efficiency
Weight Loss
Ovarian Drilling
Surgical removal of Cysts

25. REFERENCES