Age and Female Fertility
The single most important factor influencing your chance of conceiving is a woman’s age. Once you turn 36, your chance of conceiving naturally is halved compared to your chance at 20 years of age.
The reason for this is that the number of healthy (chromosomally normal) eggs you produce rapidly declines as you get older, especially after the age of 36. The number of eggs available to go through the maturing process will be lower still if you experience premature menopause, or need to undertake chemotherapy treatment. As you get older your eggs also increasingly make serious mistakes in the process of egg maturation, in readiness for the sperm entry, and unequal numbers of chromosomes are the result, leading to continuing infertility or miscarriage.
Risk of miscarriage increases with age
The egg has 46 chromosomes like every other body cell but it must reduce that number to 23 to match up with the 23 new chromosomes which the sperm brings. As you get older, your egg nucleus often divides abnormally, distributing unequal amounts of genetic material – causing an increased chance of genetic abnormality. Unfortunately, this means that for older women it’s not just more difficult to fall pregnant, there is also a greater risk of miscarriage, and of giving birth to a baby with a genetic abnormality such as Down Syndrome.
Assisted conception can help
The good news is that with advances in reproductive technology, including IVF and other forms of assisted conception, you can improve your chances of conceiving and carrying a child. Here are a few examples – visit our Fertility Services pages to find out more.
IVF
If you use IVF or other assisted reproductive technology, you can increase your chances of falling pregnant. If you are aged 36 to 40, your chance of falling pregnant with IVF is 35%, compared with 5-8% per month if you've been trying to conceive naturally for more than six months.
Genetic testing
Preimplantation Genetic Diagnosis (PGD) is a method of testing embryos for specific genetic and chromosomal abnormalities before implantation. We can also select the embryo with the greatest chance of pregnancy success.
Fertility preservation
A woman’s most fertile years are when she is in her 20s and early 30s. It is now possible to store unfertilised eggs for use in the future, using egg freezing. For women who are not in a position to become pregnant, or whose fertility is at risk due to serious illness, this relatively new technique offers the potential to still have a family later.
> Find out more about fertility preservation
> Find out more about testing your fertility (link to AMH test)
