大象传媒

What role do hormones play in human reproduction? - OCR 21st CenturyThe use of hormones to treat infertility - Higher

Hormones are vital to enable sexual reproduction in humans. There are a range of hormones that interact to cause puberty in males and females, and to prepare a woman鈥檚 reproductive system for pregnancy.

Part of Biology (Single Science)The human body - Staying alive

The use of hormones to treat infertility - Higher

Fertility treatments

Some women have difficulty becoming pregnant because they don't or their eggs do not mature. Fertility drugs contain and to artificially alter the menstrual cycle and increase the chance of pregnancy. The FSH stimulates eggs to mature in the ovary and the LH encourages ovulation to occur. Through scientists applying their understanding of science to new treatments, fertility treatments have had a positive impact on many people's lives.

Fertility treatments increase a woman's chance of becoming pregnant, although the treatment may not always work. Also, because the treatment boosts the production of mature eggs, it increases the chance of twins or triplets. Multiple pregnancies carry a risk of complications, and may lead to premature or underweight babies. A couple who want to have fertility treatment should weigh up the risks and benefits of the treatment.

In vitro fertilisation (IVF) treatment

If a couple are having difficulty conceiving a child because there are issues with the quality of the man's sperm, or a woman has blocked , then in vitro fertilisation or can be used.

  • IVF 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 a dish in the laboratory (in vitro literally means 'in glass').
  • The fertilised eggs develop into .
  • At the stage when they are tiny balls of cells, one or two embryos are inserted into the mother's .

The development of microscopy techniques has allowed IVF treatments to be developed further.

A syringe in a human egg cell

In some cases, the sperm have difficulty moving so cannot fertilise the egg. Scientists can now directly inject the egg with a sperm cell. They use a powerful light microscope to carry out this technique.