Assessment of Fetal Well-being

Assessment of fetal well-being is usually performed by ultrasonographic examination of the uterus, placenta, and fetus in a mid- to late-term pregnant mare. The goal of the examination is to determine fetal and placental status related to gestational age and to identify pathology. The mare may also be examined for signs of premature labor such as an increase in mammary development, an increase in lactogenesis, the presence of vulvar discharge, and the relaxation of perineal ligaments/tissues. This chapter discusses step by step procedure for assessing fetal viability parameters such as movement and heart rate by performing the ultrasonographic examination. The fetal movement may increase the echogenicity of allantoic or amniotic fluid. Any deviation of the fetal heart rate values from normal should be correlated to fetal movement and should be checked again on secondary examinations.