Having a dog can have an effect on pregnant women. Dogs are prone to parasites, the most common of which is Toxoplasma gondii. Toxoplasma gondii is a very harmful bacterium for pregnant women, and infection with Toxoplasma gondii increases the risk of fetal miscarriage and developmental malformations, which can lead to multiple malformations in the baby. Therefore, pregnant women are advised not to keep dogs during pregnancy, and not to keep cats either. Pregnant women who have had frequent contact with kittens and puppies before pregnancy should be sure to undergo the four eugenics tests, mainly for toxoplasmosis virus and rubella virus infection. Also, dogs are prone to accidents during pregnancy, and puppies may accidentally injure pregnant women, in which case vaccination is required.