The article represents clinical and pathoanatomical analysis of a case of full-term pregnancy with hypoplastic left heart syndrome (HLHS) in one of the twins, which occurred using in vitro fertilization (IVF). The dead macerated fetus with malformations after selective feticide at the 20th week of pregnancy and dichorial diamniotic placenta were studied. In connection with the expressive autolytic changes in the internal organs of the fetus, which do not allow to confirm the diagnosis of left ventricular hypoplasia at autopsy and establish its type of structure, additional measurements of the heart structures of the fetus with HLHS on archived video materials of ultrasound diagnostics were performed. After calculating the diagnostic indices: the index of myocardial layer thickness (ratio of the thicknesses of the trabecular and compact myocardium), the index of cavity shape of the heart in frontal axis (ratio of width to cavity length), cavity-myocardial index (ratio of wall thickness to cavity width), the cylindrical LV structure was retrospectively determined, which is prognostically unfavorable any kind of surgical correction, which justified selective feticide. The article presents the values of diagnostic indices for identifying the types of structure of hypoplastic LV. Prenatal determination of LV type determines treatment tactics: terminate pregnancy in case of adverse LV types, recommend Norwood procedure in the neonatal period with type I or perform fetal aortic valvuloplasty with type II of LV. The maturation disorders (distal villous hypoplasia) that we found in the placenta of a living fetus confirms that, despite the relatively satisfactory condition of the newborn, pregnancies that occur with the use of IVF are high risk group of developmental disability both the fetus and placenta.