If the idea of a safe,natural pregnancy panacea sounds too good to believe, your assessment is ultimately correct. Although I have known many women who have used dong quai during pregnancy, and although I know midwives who recommend it, dong quai's safety during pregnancy is questionable. While it may be worth the risks for some women, here are some potential problems associated with the use of dong quai during gestation.
Bleeding
Dong quai is a powerful anticoagulant, or blood-thinner, so it dramatically increases the risk of bleeding and bruising-- even in people who are not pregnant. Many women report excessive menstrual bleeding while using dong quai. These effects could be even more pronounced during pregnancy, and may lead to uterine bleeding that harms the developing baby. It can also mimic symptoms of pregnancy complications like miscarriage, preterm labor, ectopic pregnancy, and molar pregnancy.
Miscarriage
Although some midwives recommend dong quai for the prevention of miscarriage, evidence of its efficacy is contradictory. Some evidence suggests that dong quai can prevent miscarriage by relaxing the uterus and preventing contractions, but other evidence demonstrates that it contracts the uterus and may expel a developing embryo. Compounds in dong quai could also, in theory, poison an unborn baby and lead to its death. It's best to use safer techniques to treat threatened miscarriages.
Preterm Labor
Because of speculation that dong quai can trigger contractions in the uterus, it's quite possible that it increases the risk of preterm labor. Historically, TCM midwives have used dong quai to induce labor in women with post-term pregnancies. Although some midwives still approve of dong quai during the third trimester or the final two weeks of gestation, almost all health care providers urge women to avoid dong quai during the second trimester, since it could cause preterm delivery.
Birth Defects
There is scant evidence linking dong quai to birth defects, but one unsettling case report suggests that it increases the risk of serious congenital defects in the baby, particularly when used early in pregnancy. One woman used a combination of medicinal herbs during her first trimester. The baby was later born with serious birth defects, and experts believed that the herbs were to blame. Although this does not necessarily mean that dong quai is inherently dangerous, it does urge caution for pregnant mothers using medicinal herbs. Consult your obstetrician or midwife before using any herb, drug or supplement during pregnancy.