The clinical effects of EPO are thought to be largely due to its content of the fatty acid GLA which can have immune-modulating and anti-inflammatory effects. While less thoroughly studied, EPO is also a source of polyphenols which likely contribute an anti-inflammatory and antioxidant benefit.[1] In the body, GLA is a precursor for dihomo-gamma-linolenic acid (DGLA), which can in turn be metabolized into eicosanoids with anti-inflammatory properties, such as prostaglandin E1.[2] Cervical ripening and labor induction during childbirth both depend on prostaglandins, and increased synthesis of prostaglandin E1 is thought to be the main mechanism by which EPO may increase cervical readiness.[3] Similarly, misoprostol, a medication that is used to prepare the cervix for labor induction, is a prostaglandin E1 analog.[4]
How does evening primrose oil work?
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•Last Updated: May 16, 2025
Evening primrose oil (EPO) works primarily through its fatty acid GLA, which has immune-modulating and anti-inflammatory effects, and it is a precursor to anti-inflammatory eicosanoids like prostaglandin E1. This mechanism is thought to enhance cervical readiness for labor by increasing prostaglandin E1 synthesis.