When a woman has a severe reaction to pregnancy, it is usually due to the sensitivity of the pregnant woman’s body, the stimulation of HCG hormone after pregnancy and the combination of emotional and environmental factors. The majority of pregnant women with severe reactions have higher HCG, which is why many women with twins have more severe vomiting reactions. The fact that a woman has a severe reaction to pregnancy does not necessarily mean that her embryos are of normal quality, so a very small percentage of women with severe pregnancy vomiting will also experience embryonic abortion.