Veratrum californicum (Hellebore): Vomiting, cramps
Notes:
Cyclopia, an even more severe abnormality of brain and face (shown here), may occur among the offspring of pregnant sheep that eat Veratrum californicum. Hellebore, a plant that is a member of the same genus, is recommended in humans as a natural treatment for vomiting, cramps, and poor circulation, three conditions that are quite common in pregnant women.
No rigorous scientific evaluation of the effects of herbal treatment with hemlock or hellebore in human pregnancy is available, but these observations in domesticated animals certainly raise concern.
Image credit: University of Pennsylvania, School of Veterinary Medicine (http://cal.vet.upenn.edu/poison/index.html)