The vascularization of the lung is primarily provided by the pulmonary artery, which is, in most cases, the sole vessel responsible for transporting the blood volume from the pulmonary trunk, originating from the right ventricle to the pulmonary parenchyma. In fetal life, there is a greater vascularization compared to the adult lung, due to the process of pulmonary organogenesis, which encompasses several phases: embryonic (4 to 6 weeks), pseudo glandular (5 to 16 weeks), canalicular (16 to 24–26 weeks), saccular (24–26 weeks until birth), and the alveolar period (32 weeks until 2 years) .1 The arteries typically present for the upper lobes in adults are two for the right upper lobe, the apicoposterior branch (which is the most voluminous and consistent)2 and the anterior branch. For the left upper lobe there are three branches: the anterior branch, the apicoposterior branch, and the lingual branch. Although, as a general rule, five main branches are typically described, there are variations in adults that were studied by Johnson and Kirby in 1952. The most common variations include the origin from a common trunk of the aforementioned arteries, with a higher prevalence in the left lung.3 Previous studies conducted by the same authors have shown an increase in vascularization in fetuses of different gestational ages, consistent with the patterns presented in academic embryologic texts. However, this vascularization did not increase uniformly; instead, it was concentrated in the upper lobes. Therefore, the present study aims to classify the branching patterns of the vasculature in the upper lobes of both lungs.