Maternal environmental stresses These conditions often produce an adverse uterine environment that is incompatible with fetal development. Fetal death may occur at any stage of pregnancy, resulting in abortion. Hypothyroidism Associated with increased danger of miscarriage in women. Lower than normal levels of circulating thyroid hormone may cause infertility in the bitch. Hypoluteoidism Deficient progesterone has been suggested as a cause of abortion in several animal species.
Progesterone is required for the maintenance of pregnancy in the bitch.
Nutritional deficiencies Energy and vitamin demands increase during pregnancy. If these are deficient, fetal survival may be compromised. Dexamethasone, a commonly used anti-inflammatory agent, has been reported to cause intrauterine death and resorption of fetuses when given to pregnant bitches. Infectious conditions associated with loss of pregnancy in the bitch. Maternal environmental stresses Infectious agents gain access to the pregnant uterus via the blood stream or through the cervix.