Unit 11 - controlling fertility Flashcards
men are _____ fertile
continuously
what do men produce from their continuous fertility
continuous fertility results in a fairly steady concentration of testosterone being secreted and continually producing sperm in the testes
female fertility is _____
cyclical
when are women most fertile
women are most fertile for a few days during each menstrual cycle
how do you identify when a women is most fertile
you can identify when a woman is most fertile by an increase in body temperature by around 0.5 degrees Celsius after ovulation and her cervical mucus becomes thin and watery
what are the treatments for infertility
Stimulating ovulation, Artificial insemination, Intra-cytoplasmic sperm injection (ICSI) and
In vitro fertilisation (IVF)
what is stimulation of ovulation in terms of treating infertility
ovulation is stimulated by a drug that prevents the negative feedback effect of oestrogen on FSH secretion, other ovulatory drugs mimic this action of FSH and LH: these drugs can cause super ovulation that can result in multiple births or be used to collect ova for IVF programmes.
what is artificial insemination
artificial insemination is where several samples of semen are collected over a period of time. this is useful if the male partner has a low sperm count. if a partner is sterile a donor may be used to provide semen.
what is intra-cytoplasmic sperm injection (ICSI)
When mature sperm are defective or very low in numbers ICSI can be used. ICSI is when the head of a sperm is drawn into a needle and injected directly into the egg to achieve fertilisation.
what is In Vitro-fertilisation (IVF)
IVF is the surgical removal of eggs from ovaries after hormonal stimulation where they are mixed with sperm in a culture dish. The then fertilised eggs are incubated until they have formed at least 8 eight cells and are then transferred to the uterus for implantation, before the embryo is inserted one or two cells can be removed and tested for single-gene disorders and chromosomal abnormalities.
what are the two different methods of contraception?
The barrier method and the chemical method.
What is a barrier method of contraception and give examples.
a barrier method of contraception acts as a barrier preventing sperm from fertilising an egg.
examples of this are:
condoms - placed over the penis before and kept on during sexual intercourse.
Diaphragm - a dome shaped rubber cap inserted into a woman’s vagina to block her cervix before sexual intercourse.
Cervical Cap - a rubber structure which fits tightly around the cervix.
Intra-uterine device (IUD) - A T-shaped structure inserted into the uterus for many months or even years.
Vasectomy - A sterilisation procedure which involves the cutting and tying of two sperm ducts, so no sperm are released during sexual activity.
Tubal Ligations - A sterilisation procedure which involves the cutting and tying of a woman’s oviducts to prevent eggs from meeting sperm.
give examples of chemical methods of contraception.
oral contraceptive pill - a chemical method of contraception containing a synthetic oestrogen and progesterone that mimics negative feedback preventing the release of FSH and LH from the pituitary gland.
Progesterone-only ‘mini’ pill - causes thickening of the cervical mucus and reduces the viability of sperm, they do not contain synthetic oestrogen.
‘Morning after pill’ - contains higher doses of oestrogen and progesterone than the standard oral contraceptive pill. taken after unprotected sex to prevent or delay ovulation.
when can the ‘morning after pill’ be taken, and what is it used for
the morning after pill can be taken 72 to 120 hours after unprotected sex to prevent ovulation.
