This study aimed to investigate the connections between the echocardiography indices of fetal ductus arteriosus premature constriction and newborn prognosis by analyzing 22 cases of spontaneous fetal ductus arteriosus premature constriction.An ultrasonic instrument was used to observe prenatal fetal heart state, combine clinical examination data and echocardiographic results after delivery, summarize the ultrasound manifestations and imaging characteristics, and analyze the prognosis of the fetus.In all cases, fetal ductus arteriosus premature constriction occurred in the third trimester of pregnancy (34 + 1 to 41 weeks), and no abnormality in extracardiac organs were observed. Seven neonates required respiratory support due to the accompanying severe tricuspid regurgitation. The remaining 15 neonates did not receive respiratory support, including 4 with severe tricuspid regurgitation, 5 with moderate regurgitation, and 6 with mild regurgitation. Significant differences were observed in the fetal right atrium size and tricuspid regurgitation severity between the neonatal respiratory support group and non-respiratory support group. Furthermore, there were statistical differences in the ductus arteriosus inner diameter and pulsation index between the two groups.The severity of fetal ductus arteriosus premature contraction accompanied by tricuspid regurgitation and right atrium enlargement can predict the immediate prognosis of the newborn and provide guidance for the clinical judgment of the timing of pregnancy termination.