A few herbal remedy initiates uterine contraction; in these cases, it is not safe to consume these herbal remedies while in pregnancy because these remedies may impact inmiscarriage; black cohosh, blue cohosh, Juniper and Juniper oil are some well known popular herbs should never be consumed while a lady is pregnant.
Some herbal remedies promote some other major complications like premature labor pain or initiates the possibility of miscarriage if not treated timely and properly. Comfrey leaves have certain toxic materials in it which can penetrate placenta and initiates miscarriage with the carrying mother. Equally cumin seeds powder may result in abdominal cramping but in some specific conditions, it may cause lead to sudden miscarriage.
Other than these herbs, Rue, Peruvian bark, and Wormwood based herbal medicine are to be avoided during pregnancy period. Consumption of false unicorn root may induce the problem of morning sickness and nausea thus should be avoided by the pregnant ladies. Wormwood based herbal should also be avoided during lactation period.
*Go Herbal Remedies (2009)*
Stay Blessed & Happy Locing!