Chamomile tea is not considered safe during pregnancy, particularly in large or frequent amounts. While an occasional cup is unlikely to cause harm, the available evidence links regular chamomile consumption to risks including preterm birth, low birth weight, and possible effects on fetal circulation. The American Academy of Family Physicians lists chamomile among the herbal teas pregnant women should avoid.
Why Chamomile Raises Concerns
Chamomile has mild muscle-relaxing and anti-inflammatory properties, which is exactly why people drink it before bed. But those same properties may affect the uterus. Chamomile has long been classified as a potential uterine stimulant, meaning it could trigger contractions or increase uterine activity. This is the core reason it appears on cautionary lists for pregnancy.
A case report published in a major obstetrics journal documented fetal ductus arteriosus constriction (a narrowing of a key blood vessel in the developing baby’s heart) in a woman who substituted chamomile tea for caffeinated tea during her second and third trimesters. The ductus arteriosus is supposed to stay open until birth, so premature constriction can affect how blood flows through the baby’s circulatory system. This is a single case, not a widespread study, but it illustrates the type of concern that makes doctors cautious.
What the Research Shows
The strongest evidence comes from studies looking at chamomile use during the third trimester. One study found that women who drank chamomile tea in their third trimester had significantly higher rates of preterm birth and delivered babies who were shorter and had lower birth weights compared to women who didn’t use chamomile. A separate study looking specifically at birth weight found a trend toward lower birth weight with chamomile use, though that result fell just short of statistical significance.
A 2013 study in Iran tested chamomile in a more concentrated form: 1,000 milligrams of chamomile given every 8 hours for a week to post-term women, essentially trying to see if it could help induce labor. That dosage is far beyond what you’d get from a cup of tea, but the fact that researchers tested chamomile as a labor-inducing agent tells you something about its recognized effects on the uterus.
The overall picture is that no large, high-quality clinical trial has definitively proven chamomile tea is dangerous in small amounts. But the existing evidence consistently points in one direction: regular use, especially later in pregnancy, carries real risk.
The Difference Between One Cup and Daily Use
Most of the concerning findings involve regular or heavy chamomile consumption, not a single cup on a stressful evening. A standard cup of chamomile tea brewed from a commercial tea bag contains roughly 1 to 2 grams of dried chamomile flower, steeped for a few minutes. That’s a much lower dose than the concentrated capsules used in clinical studies.
Still, no established safe threshold exists for pregnant women. Unlike caffeine, where most guidelines agree that up to 200 milligrams a day is acceptable, there is no equivalent number for chamomile. The AAFP’s recommendation is simply to avoid it. Australia’s national pregnancy resource echoes this, advising against drinking chamomile tea “in large quantities” and noting associations with both miscarriage and preterm labor.
If you’ve had a cup or two without knowing about these concerns, that alone is not a reason to panic. The risks appear to scale with frequency and amount.
Allergy Risk With Ragweed Sensitivity
Chamomile belongs to the same plant family as ragweed, daisies, and chrysanthemums. If you have a ragweed allergy, chamomile can cross-react and trigger symptoms ranging from tingling lips and tongue to swelling in the mouth and throat. During pregnancy, when your immune system is already shifting, an unexpected allergic reaction is especially unwelcome. If you’ve ever had seasonal allergies to ragweed, chamomile tea is worth skipping entirely.
Safer Alternatives for Sleep and Relaxation
Many people reach for chamomile tea specifically because they’re struggling with sleep during pregnancy, which is extremely common. A few alternatives carry less concern:
- Warm water with lemon or honey: The ritual of a warm drink before bed can be soothing on its own, and neither ingredient poses pregnancy risks in normal amounts.
- Ginger tea: Generally considered safe in moderate amounts during pregnancy and can also help with nausea, though very high doses should be avoided.
- Decaffeinated black or green tea: These go through well-understood processing and don’t carry the same uterine stimulant concerns as herbal blends.
Be cautious with other herbal teas as well. Many herbal blends marketed as “sleepy time” or “calming” teas contain chamomile as a primary ingredient, sometimes alongside other herbs like licorice or peppermint that also appear on pregnancy caution lists. Check the ingredient list rather than relying on the front label.
The Bottom Line on Chamomile and Pregnancy
Chamomile tea is one of those things that feels harmless because it’s natural, widely available, and gentle-tasting. But “herbal” doesn’t mean “safe for everyone in every situation.” The evidence, while not extensive, consistently suggests that regular chamomile tea consumption during pregnancy is associated with adverse outcomes, particularly in the third trimester. An occasional sip is unlikely to be dangerous, but making it a daily habit introduces risks that simply aren’t worth taking when safer alternatives exist.