Every woman wants to give birth to a healthy child. Therefore, during pregnancy, it is important to closely monitor not only the mother's health but also the development of the fetus. Ultrasound examination in the first trimester of pregnancy is a non-invasive procedure that allows early detection of pathological changes in pregnancy and developmental defects of the fetus. Why is ultrasound examination necessary in the first trimester of pregnancy? The first trimester of pregnancy (from week 1 to week 13) is the most important and challenging period because it is during this time that the internal organs and body systems of the baby are formed, which determine the child's future health. Ultrasound diagnostics in the first trimester is performed between the 11th and 13th weeks of pregnancy. The main objectives of this examination are: • Clarification of gestational age; • Determining the location of the fetus (presence of one or more embryos, their attachment site to the placenta); • Assessing fetal development (comparing the size and development of limbs, spine, and other body parts to the norms for gestational age, etc.); • Evaluating the quality and volume of amniotic fluid; • Identifying the risk of miscarriage, if it exists; • Analysis of ultrasound markers of chromosomal abnormalities (measurement of the nasal bone, thickness of the nuchal translucency (NT), measurement of the biparietal diameter of the fetal head); • Exclusion of major abnormalities in the development of the brain, skeleton, heart, and some internal organs. Ultrasound examination during pregnancy allows expectant parents and the attending physician to obtain detailed information about the health and development of the unborn child, as well as to determine the risk level of the baby being born with intrauterine developmental defects, chromosomal, and hereditary diseases.