Fennel (Foeniculum vulgare) has been used traditionally for digestive support, muscle relaxation, and menstrual comfort. Modern research has begun to explore these traditional uses in controlled settings.

A study published in the Eastern Mediterranean Health Journal (2006;12(3–4):423–427) compared fennel extract with mefenamic acid, a commonly used non-steroidal anti-inflammatory drug (NSAID) for menstrual pain. The study involved high school girls who were randomly assigned to receive either fennel extract or mefenamic acid for two months.

What the study found

  • Pain improvement:

    • 80% of the girls taking fennel reported reduced pain or complete pain relief

    • 73% of those taking mefenamic acid reported similar improvement

  • Ability to continue daily activity:

    • 80% of participants in the fennel group no longer felt the need to rest during painful periods

    • 62% in the mefenamic acid group reported the same

These findings suggest that fennel may offer a meaningful level of comfort comparable to a standard NSAID for some individuals, while also supporting daily functioning. More research is needed, but this study helps explain why fennel remains a popular traditional herb for menstrual support.