Flashcards in Unit 2: The biology of controlling fertility Deck (22)
When are the males fertile and why is this?
In men fertility is continuous. Levels of testosterone, FSH and ICSH are kept relatively constant through negative feedback. As a result sperm are produced continually.
When are females fertile and why is this?
Female fertility is cyclical, with the fertile period being 1-2 days following ovulation
What can be used to measure a females fertile period?
Indicators like temperature and cervical mucus can be used. A slight rise in body temperature by 0.5 degrees and the viscosity of the cervical mucus (becomes thin and watery giving sperm easy access)
How can a women be infertile due to hormones?
A women can be infertile due to a failure to ovulate because she is not producing enough of the hormones FSH and LH.
How can a women who is infertile due to failure of ovulation by not producing enough FSH or LH be treated?
Ovulation can be successfully stimulated by drugs that contain hormones which can mimic the action of FSH and LH and drugs that can stop the negative feedback of oestrogen on FSH secretion.
What can drugs that stimulate ovulation in infertile women cause?
These drugs can cause super ovulation, resulting in multiple births or the production of many eggs for use in ovulation.
What is artificial insemination?
Artificial insemination is the insertion of semen into the female reproductive tract by means other than sexual intercourse.
What can artificial insemination be used to treat?
Artificial insemination can be used to treat infertility in men if the man has a low sperm count.
What is the process of artificial insemination?
Several samples of the mans sperm can be collected over a period of time and frozen until needed. They are then defrosted and released into the female reproductive tract at the time when she is most likely to be most fertile.
How can artificial insemination be used if a man is completely infertile?
A sperm donor can be used with the same process.
What does ICSI stand for?
Intra-cytoplasmic sperm injection.
What can ICSI be used to treat?
ICSI can be used to treat fertility in a man if the mans sperm count is low, or if his mature sperm are defective in some way.
What does ICSI involve?
ICSI involves the head of a sperm being drawn up into a needle to be injected directly into an egg to achieve fertilisation.
What does IVF stand for?
In vitro fertilisation.
What fertility issues is IVF used for?
Possible reasons for infertility could include the blockage of a woman's oviduct.
What does ' in vitro' stand for?
it stands for fertilisation outside of the body, in a culture dish.
What are the steps involved in IVF?
1) The women is given FSH and LH to stimulate the maturation of several eggs in the ovary.
2) The eggs are collected from the women and fertilised by sperm from the man in a culture dish in the laboratory.
3) The fertilised eggs are incubated until they develop into embryos.
4) At the stage when they are tiny balls of at least eight cells, one or two embryos are inserted into the woman's uterus (womb).
What are possible treatment methods that can be used to treat a failure to ovulate?
Drugs that prevent the negative feedback effect of oestrogen on FSH secretion or ovulatory drugs that can mimic the action of FSH.
What are possible treatment methods that can be used to treat blocked oviducts?
In vitro fertilisation.
What are possible treatment methods that can be used to treat low sperm count?
What are possible treatment methods that can be used to treat mature sperm defection?
Intra-cytoplasm sperm injection.