Properties and Benefits
Willow bark extract's primary active constituent is salicin, a potent medicinal compound. When the human body metabolizes salicin, it converts it into salicylic acid, a compound that is very similar to modern aspirin. The UMMC regards white willow extract as an anti-inflammatory medicine, a pain reliever and a fever reducer. It may relieve common discomforts associated with pregnancy, including headache, back pain and cramping. However, there is no evidence that its use in pregnancy is worth its significant dangers.
Bleeding Concerns
Like aspirin, white willow extract has powerful anticoagulant effects, meaning that it inhibits blood clotting. These effects pose a serious concern during pregnancy, when issues such as vaginal bleeding can threaten the viability of the pregnancy. Additionally, the use of white willow extract close to the end of pregnancy could lead to hemorrhage before, during or after labor. Women using white willow extract may also experience unusual bleeding of the gums, nose or other thin tissues.
Effect on Prostaglandins
Mayo Clinic obstetrician Roger W. Harms expresses significant concern regarding the safety of aspirin, which is chemically similar to white willow bark, in pregnant women. He notes that the compound disrupts the production of hormones known as prostaglandins, which are essential for re-routing a newborn baby's circulatory system after childbirth. When these hormones are disrupted, a baby's blood flow does not shift to accommodate the lungs, rather than the placenta, as the source of oxygen in the body. This can lead to fatal consequences.
Alternative
White willow extract's theoretical benefits are not worth the serious risks to an unborn baby or an expectant mother. Although many pregnant women believe that medicinal herbs are safe alternatives to pharmaceutical drugs, many can cause serious side effects comparable to their conventional counterparts. Safer pain relievers during pregnancy include acetaminophen, or Tylenol, and drug-free treatments such as relaxation and massage. Consult a licensed midwife or obstetrician before using any drug or supplement during pregnancy.