Men, age and fatherhood
Publication Date:09/07/2008
You may have read news reports about the effect of a man's age on their chances of fathering children. Some reports say that one in three pregnancies where the man is over 40 will end in miscarriage. But is that really true? We take a closer look at the research.
What do we know already?
Most people know that getting older makes it harder for a woman to get pregnant and increases her chances of having a miscarriage. That's partly because the quality of a woman's eggs declines over time. There has been less research into the effect of a man's age on their fertility.
But we do know that sperm, like eggs, are more likely to be damaged as men get older. This damage can make it harder for the sperm to fertilise an egg. And if a damaged sperm does fertilise an egg, there's a higher risk of the pregnancy ending in miscarriage.
Until now there hasn't been much research about how many pregnancies are affected, and at what point a man's age starts to make a difference.
What does the new study say?
The new study looked at a big group of people who were having treatment for fertility problems. That's important to remember, because it means these results may not apply to everyone. You'd expect to find more problems with pregnancies in a group of people who needed fertility treatment, compared to the general population.
As expected, women aged 38 or older had less chance of getting pregnant, and more chance of having a miscarriage if they did get pregnant, compared to women aged under 35.
But researchers also found that men aged 35 or older had more chance of their partner's pregnancy ending in miscarriage, compared to men under 35. Older men were also slightly less likely to make their partner pregnant than under-35s, but this difference was so small it could have been down to chance.
Tell me more about the study's findings
All the couples in the study had a type of fertility treatment called intra-uterine insemination, where prepared sperm from the man is injected directly into the womb of the woman. This can be helpful if the man's sperm don't swim well.
The researchers found that the number of pregnant women having miscarriages after treatment went up with the man's age, regardless of how old his partner was.
- In the partners of men younger than 35, the miscarriage rate was 14 to 17 in 100.
- In the partners of men aged 35 to 40, the miscarriage rate was 20 in 100.
- In the partners of men aged 40 or over, the miscarriage rate was 33 in 100.
Where does the study come from?
The study was carried out by French researchers from the Eylau Centre for Assisted Reproduction in Paris, France. It was presented to a conference of specialists in fertility medicine in Barcelona (the Annual Meeting of the European Society of Human Reproduction and Embryology).
How reliable are the findings?
The study was presented to a medical conference, not published in a medical journal. That means one of the researchers gave a presentation of the results to all the doctors and journalists attending the meeting. We've looked at some of the results. But the full results of the study have not yet been published in a medical journal, so we have not been able to look at them in detail. It's harder to know for sure if the results are reliable.
What does this mean for me?
The figures in the study don't say what will happen to you as an individual. These are statistics from a group of people all having one type of fertility treatment. So the pregnancy rates may be lower than in the general population, and the miscarriage rates may be higher. We don't know what the chances of miscarriage are for men at different ages who haven't needed fertility treatment.
However, if you are having fertility treatment and the male partner is over 35, you may want to discuss this with your doctor. It may play a part when your doctor talks to you about which types of fertility treatment are likely to work best for you personally.
What should I do now?
If you are having fertility treatment and you're concerned about the chances of success, ask your doctor to talk to you about the results for people your age, in the clinic where you are being treated. This gives you the best idea of your own chances of a successful pregnancy.
From:
Belloc S, Cohen-Bacrie P, Benkhalifa M, et al. The effect of maternal and paternal age on pregnancy and miscarriage rates after IUI. Presented at the 24th Annual Meeting of the European Society of Human Reproduction and Embryology, Barcelona, on Monday 7 July 2008.
To find out more about intra-uterine insemination and other fertility treatments, see our information on infertility.
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This information does not replace medical advice. If you are concerned you might have a medical problem please ask your Boots pharmacy team in your local Boots store, or see your doctor.
