Reproductive Cycle Flashcards
Male reproductive hormone
Testosterone produced by testes
Testosterone
Stimulates testes to produce sperm
Female reproductive hormone
Oestrogen produced by ovaries
Ovulation
Eggs maturing in the ovaries then released
Menstrual cycle
Every 28 days when an egg matures, is released
And either fertilises or leaves the body as a period
Day 1-7 of menstrual cycle
When the period happens
Unfertilised egg and uterus lining leaves the body
Day 8-11 of menstrual cycle
Lining of uterus rebuilds to become thick and spongy
Egg begins to mature
Day 12-15 of menstrual cycle
A mature egg is released from ovary (ovulation)
Day 16-20 of menstrual cycle
Egg travels through fallopian tube to the uterus
As the uterus wall builds up
Day 21-28
Egg remains in uterus and waits for a sperm so it’s fertilised
FSH
Causes an egg to mature in ovary
LH
causes matured egg to now be released in ovulation
Oestrogen and progesterone
Maintains uterus lining that develops in case of fertilised egg
Where is FSH released?
Pituitary gland
Journey of FSH
Produced in pituitary gland
Travels in blood (plasma) to ovaries where it causes egg to mature
Triggers production of ovaries to make oestrogen (release)
When is oestrogen produced?
When FSH travels to ovaries it triggers ovaries to make oestrogen
Oestrogen journey
Produced in ovaries to maintain uterus lining
Also stops pituitary gland protecting any more FSH to stop maturing of egg (inhibition)
Then triggers release of LH to release the egg (release)
What stops the production of FSH?
Oestrogen
LH journey
Produced in pituitary gland
Which travels to ovaries to begin production of progesterone
Where is progesterone produced?
In the ovaries
Progesterone journey
Stops release of LH so no more ovulation
Keeps lining of uterus thick for fertilised egg in case it develops
If pregnancy happens, released by placenta so no more period whilst pregnant
What decreases progesterone levels?
If the woman doesn’t become pregnant
Summary of menstrual cycle hormones
Level of FSH rises triggering ovaries to release oestrogen
As oestrogen level increases, it inhibits production of FSH so it falls
Oestrogen also triggers release of LH
LH triggers ovulation here so the ovary now releases progesterone to maintain uterus lining
However if fertilisation doesn’t happen, progesterone falls and period is had
Contraception
Means of preventing pregnancy
How do birth control pills work?
Contains hormone which prevents body producing FSH
So the egg will not mature
Advantages and disadvantages of birth control pill
Adv = highly effective if taken correctly
Disadv = must be taken every day, many side effects, forgetting to take it = risk of pregnancy
How do implants, skin patches or injections work?
Contains progesterone which prevents maturing and release of egg because it inhibits ovulation
Adv or disadv of skin patches, injections or implants?
Adv = more convenient than daily pill as they last
Disadv = side effects
Main disadv of birth control/ implants/ injections/ skin patches?
Not protected against STI
Physical Contraception name
Barrier
Barrier contraception examples
Condom or diaphragm
How do barrier contraceptions work?
Prevent sperm reaching egg, not using hormones
Condom advantages
Highly effective if used correctly
No side effects as they don’t use hormones
Protective against STIs
Condom disadvantages
Can break or fall off
Diaphragm advantages
No side effects
Effective
Spermicides
Kill or disable cell so chance of fertilisation reduced
IUD
Small T shape that is inserted into uterus to prevent embryo implanting
Releases hormones to prevent fertilisation
IUD advantages
Few side effects
Highly effective
IUD disadvantages
No protection against STIs
Surgical contraception name
Sterilisation
How does sterilisation work in women?
Prevents egg from reaching uterus
How does sterilisation work in men?
Prevents speed leaving penis
Advantages of sterilisation
Highly effective
Disadvantages of sterilisation
Hard to reverse = must be sure of having no children
No protection against STIs
Most fertile time during menstrual cycle
During ovulation
Days 8-11
Natural contraception
Not having sex when woman is most fertile aka during ovulation
Disadvantages of natural contraception
Difficult to tell when woman is actually ovulating
Not effective to prevent STIs
Fertility treatments
Fertility drug
IVF
Fertility drug
Injected with FSH and LH hormones so woman will ovulate more than usual
Thus increases fertility time
IVF stages
Mother treated with FSH and LH to mature + release several eggs
Eggs are collected and sperm from father is collected
Fertilised together in a lab
Then develop into embryos inserted back into the uterus and develop normally
IVF advantages
Gives a woman chance to have a baby on its own
IVF Disadvantages
Can lead to multiple births
Stressful for parents
Physically tiring for the mother when egg is collected and inserted back in
Not high success rate
Not all embryos will be transferred into the mother, some destroyed and may be unethical
Expensive
