Caffeine and Pregnancy

What is caffeine and where is it found?

Caffeine is a mildly addictive stimulant which naturally occurs in foods and drinks such as coffee, tea and cocoa. Caffeine is also used as an additive in soft drinks, energy drinks, some chewing gums and medications.

It is therefore possible that pregnant and lactating women may consume caffeine from multiple sources.

Why is it important to limit caffeine intake during pregnancy?

The amount of caffeine an unborn baby (foetus) is exposed to is very close to the amount consumed by the mother. This is because caffeine can be absorbed freely across the placenta, but it cannot be broken down by either the placenta or the foetus.

What are the risks associated with caffeine intake during pregnancy?

Caffeine intakes of over 200mg per day (as little as 1 – 2 cups of coffee) consumed during pregnancy is associated with preterm delivery and lower birthweight babies. High caffeine intakes are also linked with increased blood pressure and heart rate, and may lead to dehydration.

Higher intakes of over 400mg per day (e.g. 2 – 4 cups of coffee) have been shown to increase the risk of miscarriage and sudden infant death syndrome.

These adverse effects go up as caffeine intake is increased - the higher caffeine intake is, the more the birthweight if the baby is affected.

These effects were also seen in women who were non-smokers. Smoking during pregnancy is well known to adversely affect foetal growth.

How much caffeine is safe during pregnancy?

The guideline for the upper limit of caffeine intake has been set to 200 mg per day throughout pregnancy, from all sources. This equates to roughly 1 – 2 cups of coffee (depending on brand and cup size).

The amount of caffeine consumed during pregnancy and when planning a pregnancy should be limited to less than 200 mg per day.

How much caffeine is safe during breastfeeding?

Some caffeine is transferred to breastmilk. It does not enter freely into breastmilk, and concentrations in breastmilk are lower than those found during pregnancy in the mother’s blood. However, caffeine is eliminated much more slowly from pre-term and newborn infants than from adults.

Caffeine transferred to breastmilk can also cause irritability and poor sleeping patterns in infants.
Despite this, moderate intakes of caffeine are compatible with breastfeeding. An intake of 2 – 3 cups of caffeinated beverages (corresponding to around 200 – 300 mg of caffeine) per day is considered to have no adverse effect.

How do I know how much caffeine is in foods and drinks so that I can limit my consumption during pregnancy?

The table below outlines the caffeine content of commonly consumed beverages and foods in Ireland.

From this table, the daily limit of 200 mg of caffeine can still include as much as one cup of brewed coffee or two cups of tea per day.

Food or Drink	Portion Size	Caffeine Content (mg)*
Coffee, brewed	1 cup	Ranges from 102 to 200 mg
Espresso	1 shot	Ranges from 30 to 90 mg
Coffee, instant	1 cup	Ranges from 27 to 173 mg
Coffee, decaffeinated	1 cup	Ranges from 3 to 12 mg
Tea, brewed	1 cup	Ranges from 40 to 120 mg
Tea, decaffeinated	1 cup	Ranges from 3 to 5 mg
Cola/ Diet Cola	1 can (330ml)	40 mg
Zero Caffeine/ Caffeine-free Cola	1 can (300 ml)	0 mg
Energy drinks	1 can (250 ml)	80 mg (range
Milk chocolate	50g bar	10mg
Dark (plain) chocolate	50g bar	25mg**

Information adapted from the European Food Safety Authority (EFSA) and the Centre for Science in the Public Interest.

*All figures are approximate as caffeine content and portion sizes vary within and between brands.
The exact amount of caffeine will vary according to cup size, brewing methods and brand of tea or coffee. 1 cup = 200 ml; 1 shot = 30 ml.

**Caffeine content of dark chocolate varies based on its cocoa percentage. Higher cocoa percentages mean more caffeine.

How do I know if a beverage that is not coffee or tea contains caffeine?

Manufacturers must label their products with the following statement ‘High Caffeine Content. Not recommended for children or pregnant or breast-feeding women’ if the beverage contains at least 150mg of caffeine in 1 litre of product. This statement should appear near the name of the beverage.

The label must also include the exact amount of caffeine in mg per 100ml of product.

This information helps consumers to identify drinks that are high in caffeine.

An exemption to this rule is beverages based on coffee, tea or coffee or tea extract where the name of the food includes the term ‘coffee’ or ‘tea’.

How do I know if a food has added caffeine to it?

Foods (excluding beverages) that would not naturally contain caffeine, must be labelled with the following statement ‘Contains caffeine. Not recommended for children or pregnant women’ regardless the amount of caffeine added to them. This statement should appear near the name of the beverage.

The label must also include the exact amount of caffeine in mg per 100g of product.

This information helps consumers to identify those foods to which caffeine is added to.