In vitro fertilisation (IVF)

In vitro fertilisation (IVF)

In vitro fertilisation, or IVF, is where the ovaries are stimulated (using hormonal injections) to produce eggs. The eggs are harvested from the ovaries using ultrasound guidance and then fertilised with sperm in a laboratory incubatorThe fertilised eggs (called embryos) are then grown for up to five days. One or two of the best quality embryos are then transferred into the womb to achieve a pregnancy.

When is IVF advised?

You may be advised to have IVF for more than one reason, including:

  • One or both of your fallopian tubes are damaged or blocked
  • The sperm is reduced in quantity and/or quality
  • Your infertility is unexplained
  • Your ovarian reserve is low
  • To allow egg donation
  • As part of an egg or embryo freezing program

How does IVF work?

During natural conception, an egg is released each month from the ovary. It travels down the fallopian tube to meet sperm that have swum through the cervix and womb. Fertilisation of the egg will only occur if sperm have reached the egg in sufficient numbers and are of good quality.

Once fertilised, the egg starts to divide to form an embryo and travels down the fallopian tube to reach the womb about five days later. At this point, the embryo is called a blastocyst and tries to implant.

For implantation to be successful, the womb lining has to be prepared and thickened by the hormone progesterone.

The single most important factor enabling the blastocyst to continue to grow in the womb, leading to pregnancy, is the embryo’s genetic health. This depends on both the egg and the sperm.