Is herbal tea safe during pregnancy?

The verdict

Yes, in moderation, and the UK is the only country that has put a number on it: the NHS says do not drink more than 4 cups of herbal tea a day, and avoid any tea containing liquorice root.

That is a real limit with a real reason behind it, and the reason is not that herbal teas have been shown to be harmful. It is that they have barely been studied. The NHS states it plainly: there is not much research on the effects of drinking herbal teas in pregnancy, so it is safest to limit how much you drink.

Green tea, black tea and white tea are not herbal teas. They are made from Camellia sinensis, they contain caffeine, and they have no cup limit of their own - they count towards the 200mg daily caffeine ceiling instead, at roughly 75mg per cup on NHS figures.

Why herbal tea is treated differently from ordinary tea

Ordinary tea is one plant. Herbal tea is a category covering hundreds of botanicals with nothing in common except the brewing method, and that is the entire problem.

A herbal infusion is a low-dose extract of a plant, and plants make pharmacologically active compounds. Some are inert at cup strength. Some are not. Chamomile, peppermint, ginger, rooibos, fennel, hibiscus, nettle and raspberry leaf are chemically unrelated to each other and there is no reason to expect them to behave the same way. Nobody has run adequately powered trials on herbal infusions in pregnancy for any of them, and nobody is likely to.

There is also no dose standardisation. Two chamomile teabags from different brands can differ several-fold in how much plant material they contain, how it was grown and how long you steep it. A regulator cannot write a safe intake for a product that has no defined strength.

So the guidance does the only thing available: it caps the volume and names the one ingredient it wants off the list.

Liquorice root, specifically

Liquorice root is the one botanical the NHS names on both lists - it appears under drinks to limit and again, on its own, under drinks to avoid. The NHS does give a reason: liquorice root may be harmful to your baby's development, so it is safest to avoid it.

Read that instruction literally, because liquorice root turns up as a sweetener and base note in blends that are not sold as liquorice tea - detox blends, throat and cold blends, some fennel and aniseed mixes, and many "naturally sweet" caffeine-free blends. Checking the ingredients list is the only reliable way to catch it.

Liquorice confectionery is a separate question, and most liquorice-flavoured sweets contain flavouring rather than liquorice root extract.

Ginger, and a UK position most people have not heard

Ginger tea is the standard recommendation for pregnancy nausea almost everywhere. Current UK clinical guidance does not share the enthusiasm. NICE's Clinical Knowledge Summary on nausea and vomiting in pregnancy relays the RCOG position that there are no trials of community ginger use for severe nausea and hyperemesis, and cites a survey of 512 women with hyperemesis in which ginger foodstuffs or tablets had little or no efficacy and caused unpleasant adverse effects or worsening symptoms in 54% of participants. It goes further: being told to try ginger was found to cause a loss of trust in the clinician, and RCOG advises health professionals not to suggest it, because doing so may delay access to effective treatment.

That is about ginger as a remedy for significant sickness, not about a cup of ginger tea being unsafe - no authority says it is. But it is worth knowing that the most-recommended pregnancy tea is one UK clinicians are told not to recommend.

Raspberry leaf

Raspberry leaf tea is the herbal tea most often asked about in late pregnancy, on the basis that it prepares the uterus for labour. No UK, US, Canadian, Australian or New Zealand authority endorses it, and none publishes a safety assessment either. It falls inside the general 4-cup herbal cap in the UK and outside any published guidance elsewhere. If you are considering it, ask your midwife - they will have a local policy.

How much is too much

• Herbal tea: no more than 4 cups a day, and none containing liquorice root. This is the only published herbal tea limit in any of the five countries.
• Caffeinated tea: counts against 200mg of caffeine a day, not against the herbal cup limit. NHS figures put a cup of tea, black or green, at 75mg - so roughly two and a half cups uses the whole caffeine allowance.
• Decaffeinated ordinary tea: not counted by anyone.

The two limits are separate ceilings, not one shared allowance. Four cups of peppermint tea plus two cups of black tea is within both. Four cups of green tea is 300mg of caffeine and over the caffeine limit regardless of what the herbal rule says.

If you have been drinking more than that

Nothing follows from exceeding a precautionary volume cap. The 4-cup figure is not a threshold at which something happens; it is a limit set because the evidence to set a better one does not exist. There is no test and nothing to report.

The one thing worth doing retrospectively is reading the ingredients on whatever you have been drinking, specifically for liquorice root. If it is in there, switch. If you have been drinking a blend containing a botanical you cannot identify, take the box to your next antenatal appointment - a midwife can tell you far more from an ingredients list than from a description.

Where guidance differs

Almost entirely by silence, and the silence is the story.

The NHS 4-cup rule appears to be unique in the world. No other national authority we checked publishes a herbal tea limit for pregnancy at all, and none names liquorice root.

The US publishes nothing. Neither ACOG's healthy eating guidance nor the CDC's safer food choices table for pregnant people sets a herbal tea limit or names a herb.

Australia and New Zealand publish nothing. FSANZ's higher-risk foods list covers pathogens in food categories; herbal infusions are not among them. New Zealand Food Safety's pregnancy pages contain no reference to herbal tea at all - its only drinks entries are fruit juice, kombucha and cider. FSANZ also declines to set a caffeine number, warning only that large amounts may make conception harder and may increase the risk of miscarriage or low birth weight.

Canada could not be confirmed either way. A figure of two to three cups a day of a short named list of herbs is widely attributed to Canadian federal guidance, but we could not verify it against a live Health Canada or Public Health Agency of Canada page, so we do not state it as current.

These are documents detailed enough to specify cheese varieties and internal cooking temperatures to the degree. The absence of herbal tea is not an oversight - it reflects that herbal infusions sit outside the microbiological remit those pages are written under. Nobody has taken the question on except the NHS, and the NHS's own justification is that the research does not exist.

The practical consequence: if you are outside the UK and looking for your own regulator's herbal tea limit, there probably is not one. The strictest published rule available anywhere is four cups, no liquorice root.