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 Fo