Women who have had children using IVF face a 10% greater risk of getting breast cancer, warns study
- Women aged 40 and over may have an even higher risk, scientists discovered
- The danger is thought to come from powerful drugs used to stimulate ovaries
- They trigger a spike in the hormone oestrogen, which is linked to breast cancer
- Danish researchers tracked around 600,000 women for 21 years for the study
Women who try to start a family using IVF may be putting themselves at greater risk of breast cancer.
Those who have had fertility treatment are 10 per cent more likely to get breast cancer, according to a study described as a 'wake-up call'.
Women aged 40 and over may have an even higher risk, being 65 per cent more likely to be diagnosed.
The danger is believed to come from powerful drugs which are used to stimulate women's ovaries so they produce more eggs for IVF.
Those who have had fertility treatment are 10 per cent more likely to get breast cancer, according to a study described as a 'wake-up call
That triggers female hormone oestrogen, which is needed to grow eggs but is also linked to breast cancer.
Researchers led by the University of Copenhagen tracked more than 600,000 women for up to 21 years during the study, which was presented at the annual meeting of the European Society of Human Reproduction and Embryology (ESHRE) in Vienna.
Commenting on the findings, fertility expert Professor Geeta Nargund, a lead consultant at London's St George's Hospital and medical director of Create Fertility, said: 'This is a wake-up call about the use of high dose stimulation in IVF, especially in women over the age of 40.
'We must act now as a precaution.'
The researchers looked at all women given fertility treatment, including IVF, at clinics in Denmark between 1994 and 2015.
These 58,534 women were compared to more than 560,000 women matched for age who had not used fertility clinics.
The risk of breast cancer was 10 per cent higher in women who had received fertility treatment, with eight in every 1,000 women diagnosed.
That compared with six in every 1,000 women who had not had a fertility procedure such as IVF.
Researchers looked at women who were aged 40 or over when they gave birth to their first child, finding those who used fertility treatment had a 65 per cent higher risk of breast cancer.
This may be because older women sometimes need a higher dose of drugs to stimulate their ovaries, and are more vulnerable to the oestrogen these drugs trigger.
Dr Jane Stewart, chair of the British Fertility Society, said: 'We shouldn't be complacent about long-term effects.
'Previous studies have been reassuring re breast cancer but clearly the discussion is not closed.'
But Dr Roy Farquharson, the president of ESHRE from Liverpool Women's Hospital, said the effect was 'marginal' and more studies are needed.
Most watched News videos
- Russian soldiers catch 'Ukrainian spy' on motorbike near airbase
- Trump lawyer Alina Habba goes off over $175m fraud bond
- Shocking moment man hurls racist abuse at group of women in Romford
- Moment fire breaks out 'on Russian warship in Crimea'
- Shocking moment thug on bike snatches pedestrian's phone
- Shocking moment passengers throw punches in Turkey airplane brawl
- Gideon Falter on Met Police chief: 'I think he needs to resign'
- Mother attempts to pay with savings account card which got declined
- Machete wielding thug brazenly cycles outside London DLR station
- Shocking footage shows men brawling with machetes on London road
- China hit by floods after violent storms battered the country
- Shocking moment balaclava clad thief snatches phone in London