The impact of age

It’s generally considered less than polite to ask a lady her age. But in the world of fertility, it will be the number one question you’re asked. That’s because female age is one infertility factor we can do little to combat. While Hollywood might be telling you a different story (hint - don’t believe everything you read), our experience shows that conceiving and giving birth using your own eggs after the age of 45 is extremely rare.

Now that’s obviously the upper end of the age conversation and you might be thinking, “I’m 10 years younger than that so I’m fine”. Unfortunately, and we’re not trying to be alarmist when we say this, fertility actually peaks at 22 and gradually declines from then on. Unfortunately the decline picks up pace and begins to be an issue from 33 or so, falling even more dramatically after 35.

Age works against fertility in several ways. It increases the likelihood you’ll suffer from problems with ovulation or your cycle and it also impacts on the health and number of eggs you have.

As your age advances beyond approximately 33, it’s more and more likely that your aging eggs will let the side down when it comes to conception. At first this will just be sporadically, but eventually it will be so thorough that you’ll essentially be sterile. And that can happen years before menopause. You see, the issue is that women are born with all of the eggs you’ll ever have - approximately two million and by the time of your first period, that number will have dropped to approximately 300,000. Not only is the number of eggs you have falling as you get older but the quality of the ones you have left also diminishes.

From our own research we’ve found that many couples wait for more than two years before seeking fertility treatment. The problem with that is that if you’re 36 and you decide to wait for the average time, you’ll be 38 by the time you seek treatment and your chances of conceiving could have declined.

The bottomline is - don’t wait! Get checked out to make sure there isn’t a medical issue that no amount of waiting will fix.

Impact of age on fertility

As you can see from the graph below, by the time you’re 36 your chance of conceiving per month is decreased by half - and that’s if there are no other factors at play. The downward slope continues until by age 45 the average natural fertility rate per month is approximately one per cent.

Genea graph chance of conception by age

The good news

You can read about our success rates for your age bracket to learn more.

Fertility after 40

There are several reasons why live births become rare as women pass the milestone age of 40:

  • Likelihood of fertility decreasing conditions, such as endometriosis or fibroids increases with age;
  • All the energy required for an embryo to keep dividing and growing comes from the egg, in little packets called mitochondria. As women get older, their eggs contain fewer and fewer healthy mitochondria, and have less energy available. The foetus will produce its own mitochondria once it reaches a certain point in its development, but if there is not enough energy to reach that point, development will stall, resulting in failure to fertilise, failure to implant, failure to divide, or early miscarriage;
  • If your periods are absent or irregular, ovulation is often absent or irregular too. An absence of ovulation will result in complete infertility. Ovulation can be corrected in some patients with hormones or drugs. If there are no eggs in the ovaries that respond to drug treatment, the only solution for pregnancy is to use donated eggs or embryos;
  • The occurrence of abnormal foetuses is much higher among older women. One of the best known is the chromosomal abnormality that results in Down syndrome. Chromosomal abnormalities are major contributors in the increased rate of miscarriage among older women.

Am I too old?

Of course, all of this information is general and the figures are averages. Some women will remain fertile into their 40s and other will find their fertility drops off earlier. Unfortunately it’s part of life’s lottery. 

Genea Oxford does not discriminate on the basis of age. When you comes to us for treatment, we will make sure that you are aware of the average chance of success for women in your age group, as well as the chance of miscarriage and genetic abnormality. Then we will respect your decision as to whether you would like to have treatment or not.

Give us a call or complete the below form to discuss your options.

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