Experts recommend that pregnant women limit the amount of caffeine they drink each day. Women consuming high levels of caffeine during their pregnancy can result in their baby having a low birth weight or even miscarriage. It is recommended that you do not have more than 200mg of caffeine a day, which is approximately two mugs of instant coffee,  one mug of filter coffee, two mugs of tea, five cans of cola, and four 50g bars of chocolate.