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Fertility & Pregnancy

Caffeine during pregnancy

It is imperative that women who are planning conception, are pregnant or who are breastfeeding abstain from caffeine in all forms.

Caffeine is a stimulant that increases alertness. It slightly increases blood pressure and heart rate and increases urine production. Some individuals are more sensitive to caffeine than others. Pregnant women may be especially sensitive to it because they take longer to clear caffeine from the body than individuals who are not pregnant. It has been shown that caffeine passes to the unborn baby through the placenta within 30 minutes mildly constricting blood vessels and decreasing blood flow for several hours which may harm the baby.

One study compared pregnant women who had less than 100mg/day and showed the risk of having a lower birth weight baby increased by 20% for intakes of 100-199mg/day, 40% for women having 200-299mg/day and 50% for having over 300mg. Statistics indicate that caffeine of greater than 200mg/day is linked with miscarriage and heavy intakes during late pregnancy can cause newborns to be unsettled, crying and irritable for up to three days as they withdraw from caffeine – certainly not a good prospect!

A new study found that women who consume 200mg of caffeine or more a day are twice as women who consume no caffeine likely to have a miscarriage. The source of the caffeine does not matter; the risk appears to be the same for caffeine from coffee, tea, soft drinks and other foods and beverages. Also remember that some medications and some herbal medicines such as Guarana contain caffeine. Women should be aware of this so they can limit their intake when they are pregnant or trying to become pregnant.

The caffeine addicts out there are probably reading this and thinking ‘as long as I consume less that 100mg per day I should be fine’. Theoretically this may be possible but consider how much caffeine we consume without intending do – cake, biscuits or a piece of dark chocolate etc. A lot of people also forget that green and white tea whilst healthier choices than black tea – still contain caffeine.

My suggestion is to avoid it completely from preconception until you’ve ceased breastfeeding. Better to be safe than sorry.