Most guidance leans toward skipping kombucha during pregnancy. It is usually raw (unpasteurized), it is fermented so it contains a small amount of alcohol, and it has caffeine — three things health authorities like the NHS, CDC, and FDA flag as reasons for caution in pregnancy. This page reports what those authorities say; it is not a substitute for your own provider's advice.
Kombucha is a fizzy drink made by fermenting sweetened tea with a live culture of bacteria and yeast (often called a SCOBY). Because it is fermented, it naturally contains a small amount of alcohol and live microbes. Most kombucha sold in shops is raw and unpasteurized, meaning it is not heat-treated to kill bacteria. It also carries caffeine from the tea base.
The CDC and FDA advise pregnant people to avoid unpasteurized foods and drinks, because they can carry harmful bacteria such as Listeria. The NHS advises no alcohol in pregnancy as the safest choice, and kombucha's fermentation means the alcohol content can vary and is not always clearly labeled. ACOG also recommends limiting caffeine to under 200 mg a day, and kombucha adds to that total. Home-brewed kombucha is a bigger concern, since it is not tested and can grow contaminants.
If you want a fizzy, refreshing drink, sparkling water with fruit, or pasteurized juices, are lower-risk options. Some brands sell pasteurized or alcohol-free kombucha, but check the label carefully and confirm the caffeine and alcohol content. Avoid home-brewed kombucha entirely during pregnancy. When in doubt, ask your provider before making it a regular habit.