Introduction: The ductus arteriosus is a blood vessel which connects the pulmonary artery to the aortic arch. This binding occurs opposite to the origin of left subclavian artery. The pulmonary trunk is an artery that carries deoxygenated blood from the right ventricle to the lungs. Objective: Make a morphometric study on the aorta and pulmonary artery beyond ductus arteriosus in a population of individuals between 9-26 weeks of gestation, constituting a database that can assist interventional surgeons for closure of the ductus arteriosus. Methods: It was measured weight, vertex-rump, vertex-heel lengths, head and chest circumferences, and anatomical measures concerning the ductus arteriosus of 44 human fetuses with gestational ages ranging from nine to 26 weeks. Inferential analysis was performed by Student’s t test and Pearson ?s correlation (R) and the significance level was 0.05. Results: It was observed that, among the 44 fetuses, 22.72% had gestational age between nine and 14 weeks; 61.36% had between 15-20 weeks; and 15.90% had between 21-26 weeks of gestation. Regards morphological parameters, there are significant statistical differences for some parameters, such as diameter of the aorta+ pulmonary trunk (p < 0.0001); diameter of the aorta (p: 0.01); diameter of the pulmonary trunk (p: 0.007); diameter of the ductus base at the aorta (p < 0.0001). Conclusion: It is known that the earlier the correction of patent ductus arteriosus, increased patient survival. Therefore, it is necessary to develop instruments that allow the approach in extremely preterm infants with improved modes of treatment.