While some herbal remedies say they will help with pregnancy, there have been no studies to figure out if these claims are true. Likewise, there have been very few studies to look at how safe and effective herbal remedies are. Echinacea, Gingko biloba, and St. John’s Worthave been popular herbs, to name a few. Do not take any herbal products without talking to your health care provider first. These products may contain agents that could harm you and the growing fetus, and cause problems with your pregnancy.