The Uses of Hormones to Treat Infertility (AQA GCSE Biology: Combined Science)

Higher tier only

• Infertility occurs when a couple find it difficult or are unable to conceive naturally
• This can be a result of insufficient or too low levels of reproductive hormones affecting the development of egg and sperm cells, or as a result of issues with the reproductive system of the female

Use of hormones

• Artificial hormones are used as part of modern reproductive technologies to treat infertility, particularly when the female is not producing enough eggs, usually as a result of the pituitary gland not producing sufficient FSH to cause egg maturation
• The hormones FSH and LH are given as a ‘fertility drug’ to stimulate egg production
• An important social issue to consider with this is that several eggs can be released at once so this increases the chance of multiple births (twins or triplets etc)
• It also doesn’t have a particularly high success rate and can be expensive

IVF treatment

• An alternative treatment is for eggs to be fertilised by sperm outside of the body (‘in vitro’ means ‘in glass’) – this is used particularly when there are issues with both male and female fertility
• The process involves:
  • Giving a mother FSH and LH to stimulate the maturation of several eggs
  • The eggs are collected from the mother and fertilised by sperm from the father in the laboratory
  • The fertilised eggs develop into embryos
  • At the stage when they are tiny balls of cells, one or two embryos are inserted into the mother’s uterus (womb)

• The success rate of IVF is low (~30%) but there have been many improvements and advancements in medical technologies which are helping to increase the success rate
• These advancements include improvements in microscope techniques and micro-tools that enable single cells to be removed from an embryo for genetic testing to identify if the embryo is healthy or has genetic defaults the couple might want to consider

Higher tier only

• Fertility treatments can give a couple the chance to have a baby of their own, which is a big positive
• Potential issues to consider include:
  • As several embryos are implanted, the risk of multiple births is quite high (which increases the risk of miscarriage or stillbirths)
  • The success rate is not very high (although it is increasing); IVF treatment failures can be very emotionally upsetting and physically stressful for couples
  • Some women use IVF to get pregnant at a later age than they would be able to conceive naturally
  • Some people are against IVF as more embryos can be produced than are used; the issue of who owns these embryos and whether they are used in research before eventually being destroyed is contentious (as embryos are a potential life)
  • The use of genetic testing is controversial as there is potential it could be misused in choosing characteristics of offspring (this is not allowed)