2.3 Flashcards
what is fertility
when a male is capable or fathering a child or a female is capable of conceiving and becoming pregnant
how can you identify the fertile period in women
- a rise in body temp by around 0.5°c after ovulation
- the cervical mucus becoming thin and watery
what are some causes of infertility
- age
- genetics
- disease
- anorexia
- obesity
- drug misuse
- smoking
- stress
- poor diet
what can the causes of infertility result in
- failure to ovulate
- blockage of oviducts
- failure of implantation
- low sperm count
what are the infertility treatments
- ovulation-stimulatory drugs
- artificial insemination
- in vitro fertilisation (IVF)
- intracytoplasm sperm injection (ICSI)
when would ovulation stimulators drugs be used
when there is a failure to ovulate
what do ovulation stimulators drugs do
• one type of drug prevents the negative feedback effect of oestrogen on FSH secretion meaning more FSH is released which stimulates follicular development
• other types mimic action of FSH & LH
what are the risks of ovulation stimulatory drugs
can cause super ovulation which can result in multiple births
what can ovulation stimulators drugs be used for in other fertility treatments
to collect ova for ivf
how does artificial insemination work
several samples of semen are collection over time and inserted into the female reproduction system when she is fertile
when would artificial insemination be used
when the male has a low sperm count, or if he is sterile a donor may be used to provide sperm
when would ivf be used
to treat blockage of oviducts
what are the stages of ivf
- surgical removal of eggs from ovaries after hormone stimulation
- eggs are mixed with sperm in a culture dish
- the fertilised eggs are incubated until they have formed at least 8 cells
- the suitable embryos are then transferred into the uterus for implantation
when would icsi be used
if mature sperm are defective or very low in numbers
how does icsi work
the head of the sperm is drawn into a needle and is injected directly into the egg to achieve fertilisation
what is pgd
the process used to identify single gene disorders and chromosomal abnormalities
what are the stages of pgd
- during ivf and icsi, cells are removed from the embryos to identify single gene disorders and chromosomal abnormalities
- only the suitable embryos are transferred for implantation
what is contraception
the intentional prevention of pregnancy by natural or artificial methods
what does contraception do
prevent fertilisation or implantation
what are the physical methods of contraception
- avoiding fertile periods (natural)
- barrier methods
- iud
- sterilisation
how does avoiding fertile periods (natural contraception) work
avoiding having sex during fertile periods
how do barrier methods work
condoms, diaphragms and cervical caps prevent the sperm entering the uterus and reaching an ovum
what is iud (the coil) and how does it work
it’s a small structure that’s often t-shaped with metallic copper parts
- it work by being fitted into the uterus to prevent implantation of an embryo in the endometrium
how does sterilisation work & is it reversible
usually irreversible
• vasectomy (male) - cutting and closing of sperm times
• tubal ligation (female) - cutting or closing each oviduct
