Five cups of coffee a day ’as bad as smoking’ for IVF success
DRINKING five or more cups of coffee a day - or copious amounts of tea - is as bad as smoking for women who want to get pregnant via IVF, say researchers.
The Danish team found women who drank that amount halved their chances of getting pregnant via fertility treatment, compared to those who drank none.
Dr Ulrik Kesmodel, of Aarhus University Hospital, said: “Although we were not surprised that coffee consumption appears to affect pregnancy rates in IVF, we were surprised at the magnitude of the effect.”
He described the adverse impact on IVF success as “comparable to the detrimental effect of smoking”.
Caffeine is believed to be the culprit, although nobody knows for sure.
He said: “If we believe it's caffeine which does the damage, then we need to mention tea.”
A cup of instant coffee contains about 100mg of coffee, while a cup of tea contains half that.
Dr Kesmodel said women who drank 10 or more cups of tea a day should therefore cut down.
He said five per cent of the 4,000 women they interviewed admitted drinking five or more cups of coffee daily.
He emphasised they found no effect on IVF pregnancy rates among those who drank less than that.
In 2008 the Food Standards Agency (FSA) said pregnant women should consume no more than 200mg of caffeine a day during pregnancy, after studies indicated drinking more than that could increase the risk of miscarriage and low birth weight. Its previous limit was 300mg.
At the time, the Royal College of Obstetricians and Gynaecologists said that “caffeine consumption has adverse effects on reproduction, including IVF treatment”.