Chamomile, derived from the dried flowers of the Matricaria chamomilla or Chamaemelum nobile plants, is one of the most widely consumed herbal infusions globally. This botanical remedy has long been associated with therapeutic properties, including promoting relaxation and aiding digestion. A persistent question is whether drinking chamomile tea can reliably induce menstruation, a belief rooted more in anecdotal history than modern biology. To understand this claim, it is necessary to separate chamomile’s established actions from its traditional uses and examine the scientific evidence regarding its impact on the female reproductive system.
The Primary Biological Effects of Chamomile
The established biological actions of chamomile are linked to its sedative, anti-anxiety, and anti-inflammatory characteristics. These effects are mediated by a mix of compounds, including volatile oils and flavonoids. The mild calming effect is attributed to the flavonoid apigenin, which is present in the tea.
Apigenin binds to specific benzodiazepine receptors in the brain, which are part of the GABA-A receptor complex. This interaction enhances the effect of gamma-aminobutyric acid (GABA), the brain’s main inhibitory neurotransmitter. This promotes relaxation and mild sedation, allowing chamomile to act as a mild tranquilizer and sleep-inducer used historically against anxiety and insomnia.
Chamomile also exhibits anti-inflammatory activity. The volatile oils alpha-bisabolol and chamazulene, along with apigenin, inhibit the production of inflammatory mediators. These compounds suppress the activity of enzymes like cyclooxygenase-2 (COX-2) and 5-lipoxygenase. This mechanism is similar to how many non-steroidal anti-inflammatory drugs (NSAIDs) function, allowing chamomile to reduce inflammation and muscle spasms.
Traditional Use and Scientific Scrutiny
The belief that chamomile can induce a period stems from its classification as an emmenagogue in traditional folk medicine. An emmenagogue is a substance believed to stimulate or increase menstrual flow. This traditional use is linked to the herb’s antispasmodic effects, which can relax the smooth muscle tissue of the uterus, potentially easing the passage of menstrual blood.
The mechanism connecting chamomile to the menstrual cycle centers on apigenin. Apigenin is identified as a phytoestrogen, meaning its chemical structure allows it to interact with estrogen receptors (ER) in the body, particularly the ER-beta subtype. In laboratory settings, these weak estrogenic properties suggest apigenin could theoretically alter the balance of reproductive hormones that regulate the menstrual cycle timing.
However, the concentration of apigenin in a standard cup of chamomile tea is significantly lower than the doses used in studies that demonstrate a hormonal effect. There is no robust clinical evidence that consuming chamomile tea in typical amounts can reliably induce menstruation. While studies suggest chamomile extracts may reduce the pain of primary dysmenorrhea (menstrual cramps), this is due to its anti-inflammatory and antispasmodic properties, not its ability to change the timing of the cycle.
Safety Considerations and Contraindications
While generally considered safe in standard tea quantities, chamomile carries specific safety considerations, especially when consumed to alter a biological process. Individuals with known allergies to plants in the Asteraceae family (such as ragweed, chrysanthemums, or daisies) should exercise caution. Chamomile is a member of this family and may trigger allergic reactions ranging from mild dermatitis to severe hypersensitivity.
Chamomile contains compounds that can interact with certain medications. Due to its mild sedative action, it can potentiate the effects of central nervous system depressants, including prescription sedatives and alcohol, leading to excessive drowsiness. It also contains trace amounts of coumarin-like compounds, which possess mild blood-thinning effects. This creates a theoretical risk for increased bleeding when combined with anticoagulant or antiplatelet drugs like warfarin.
The most serious contraindication for those attempting to induce a period is pregnancy. Roman chamomile, in particular, has been associated with the potential to cause uterine contractions, posing a direct risk to a developing fetus. The herb is often cautioned against during gestation. People with hormone-sensitive conditions, such as a history of breast, ovarian, or uterine cancers, endometriosis, or uterine fibroids, should also avoid regular or high-dose consumption due to the weak estrogenic activity of apigenin.