Pregnancy ‘formula’ criticised
A new formula to predict a woman’s chance of falling pregnant has been criticised for not giving couples any new answers to fertility problems.
In a study carried out by researchers from Warwick Medical School, a complex mathematical formula was developed in order to estimate a couple’s chances of falling pregnant.
The formula combines information on how the chance of fertility drops with age with the length of time a woman has been trying to start a family, to come up with the odds of conceiving in any given month.
Usually it is thought acceptable for a couple to see a doctor if they have been trying to conceive for a year or more but the aim of this formula is to help doctors to decide whether to refer patients for costly fertility treatments or to advise them to keep trying for a while longer.
Professor Geraldine Hartshorne said: “As time goes by and people have been trying for a while, they start to get stressed and upset and that can affect their chances of having sex and then becoming pregnant.
“Approaching a doctor about a personal matter is daunting, so knowing the right time to start investigations would be a useful step forward.”
One of the objectives of the research was to have an online calculator for couples trying to conceive so they can predict their chance of when they may get pregnant, thus helping their decision of whether to see their doctor or not.
But according to NHS Choices, this highly complex formula cannot really be a reliable tool for couples to use as people vary so much and it is highly unlikely to be brought into clinical use without further study.
“It is difficult to draw conclusions from the current study. The mathematical formula is highly complex and its reliability will need to be assessed with further testing.”
The research showed that for women aged from 25 to 30 there is little difference in their chances of conceiving on the next cycle, but the chances drop when a woman is 35 and up.
The advice from this research is that if you are in your mid-30′s you should go to a doctor after only 6 months of trying to conceive, rather than wait the year.
So, for all its complexity, the formula just cements the fact that it is more difficult to get pregnant as you get older rather than providing couples who are struggling to conceive with any new information on how to increase their chances.
As NHS Choices say, “Overall, the main finding of this study is not going to come as any great surprise either to fertility experts, or the general public: fertility declines with age.”