IVF, the birth of in vitro fertilisation
The IVF Revolution
|1) IVF can only be performed in a very limited group of couples i.e. those where the male has a reasonable number of sperm in his semen (i.e. >15,000,000/ml). This means many patients cannot be treated with the technique.
2) There is a real possibility of ‘fertilisation failure’ i.e. no eggs fertilized with IVF even when the prospect was good. Although this happens in about 1% of cases, it never happens with ICSI, therefore many IVF centres have become ‘all ICSI’ centres. In fact, more recently National Statistics have adopted to present their annual reports without differentiating for technique.
GIFT (Gamete IntraFallopian Transfer) is a variation on IVF. With GIFT, eggs and sperm are returned to the Fallopian tubes without in vitro insemination. The idea is to replace the gametes into the most natural environment to maximise embryo growth and development.
Which types of infertility can be treated with IVF?
Couples in which the male partner is considered normospermic or has mild subfertility are commonly treated with in vitro fertilisation. In cases where the male subfertility is more severe, ICSI, or intracytoplasmic sperm injection, is preferred.
What is the success rate based on?
In a good standard laboratory, the success rate (that is pregnancy rate) is dependent mainly on maternal age. In general, patients where the woman is below 30 years can expect a success rate in the range 55-60%. Women of between 30 and 37 years can hope for pregnancy in 40-50% of attempts and women over 37 years old can expect a 15% chance of achieving pregnancy. Of course, other factors (such as the womans hormonal status) have an effect, but the major influencing factor is maternal age.