One in six women who fail to become mothers through IVF get pregnant naturally within five years, research suggests.
Scottish scientists looked at more than 2,000 women who resorted to either IVF or intracytoplasmic sperm injections (ICSI).
More than half did not conceive or miscarried, of which 17 per cent had become parents naturally five years later.
The researchers hope this will encourage ‘distraught’ couples who incorrectly ‘equate unsuccessful treatment with the end of having a baby’.
One in six who fail to become mothers via IVF get pregnant naturally within five years (stock)
Dr David McLernon, lead author at the University of Aberdeen, said: ‘IVF treatment is not something couples take on lightly.
‘And it can be a physically and emotionally demanding process even if treatment is successful. When it is unsuccessful, understandably couples can be left distraught.
‘This study will give couples a clearer idea of their chances of conceiving naturally even after IVF has been unsuccessful.
‘Hopefully with this information they will be able to make an informed choice about their next moves after treatment.’
Infertility affects around one in six women in the UK, the researchers wrote in the journal Human Reproduction.
In the US, around one in 10 struggle to get or stay pregnant, according to the Center for Disease Control and Prevention.
The number of Britons who turned to IVF or ICSI rose by almost three times between 1994 and 2014.
ICSI involves doctors injecting a single sperm into an egg. This is different to IVF, which mixes sperm with eggs and allows them to fertilise.
What is infertility?
Infertility is when a couple cannot get pregnant despite having regular unprotected sex.
It affects one in seven couples in the UK – around 3.5 million people.
About 84 per cent of couples will conceive within a year if they have unprotected sex every two or three days.
Some will conceive quicker, and others later – people should visit their GP if they are concerned about their fertility.
Some treatments for infertility include medical treatment, surgery, or assisted conception, including IVF.
Infertility can affect men and women, and risk factors include age, obesity, smoking, alcohol, some sexually transmitted infections, and stress.
Fertility in both genders decreases with age – most rapidly in their 30s.
UK guidelines recommend IVF be offered on the NHS to women under 43 who have been trying to get pregnant for two years.
Fertility treatments have been shown to become less successful with age.
Although the success rate of IVF jumped from 14 per cent to 27 per cent from 1994-to-2014, most still do not get pregnant after their first cycle.
Many then ‘equate unsuccessful treatment with the end of any hope of having a baby’, the researchers wrote.
Few studies have looked at how many women become mothers after unsuccessful IVF or ICSI.
‘[And] most of them have been based on surveys with poor response rates and a small sample size,’ Dr McLernon said.
The researchers analysed 2,133 women who underwent IVF or ICSI between 1998 and 2001. The participants were followed for up to 15 years.
‘This study looked at data from more than 2,000 women which we think makes it one of the most robust studies of its type,’ Dr McLernon said.
Some 1,060 of the women gave birth as a result of their fertility treatment, while the remaining 1,073 either did not get pregnant or miscarried.
Five years later, 17 per cent of the 1,073 women had become mothers without IVF or ICSI.
And after 10 years, 19 per cent of those who failed to have a baby initially had children.
Of the 1,060 who did have children via IVF or ICSI, 15 per cent and 17 per cent became pregnant naturally five and 10 years later, respectively.
Women who have a baby through fertility treatment may be less inclined to have more or may be more cautious about contraception, the researchers wrote.
The participants were more likely to become pregnant if they were young and had not been struggling to conceive for long.
The researchers stress, however, the participants were only recruited from the Aberdeen Fertility Clinic and may not represent women nationwide.
They also did not monitor the women’s use of contraception or whether they were actively trying to get pregnant.
HOW DOES IVF WORK?
In-vitro fertilisation, known as IVF, is a medical procedure in which a woman has an already-fertilised egg inserted into her womb to become pregnant.
It is used when couples are unable to conceive naturally, and a sperm and egg are removed from their bodies and combined in a laboratory before the embryo is inserted into the woman.
Once the embryo is in the womb, the pregnancy should continue as normal.
The procedure can be done using eggs and sperm from a couple or those from donors.
Guidelines from the National Institute for Health and Care Excellence (NICE) recommends that IVF should be offered on the NHS to women under 43 who have been trying to conceive through regular unprotected sex for two years.
People can also pay for IVF privately, which costs an average of £3,348 for a single cycle, according to figures published in January 2018, and there is no guarantee of success.
The NHS says success rates for women under 35 are about 29 per cent, with the chance of a successful cycle reducing as they age.
Around eight million babies are thought to have been born due to IVF since the first ever case, British woman Louise Brown, was born in 1978.