Aim
The primary aim was to estimate premature infants' spontaneous patent ductus arteriosus closure rate. Secondly, to identify criteria associated with the chance of spontaneous closure.
Methods
We performed a retrospective cohort study of 167 infants born before 32 weeks of gestation and diagnosed with a patent ductus arteriosus between 1 January 2008 and 31 December 2017. The spontaneous patent ductus arteriosus closure event rate was evaluated using the Kaplan–Meier estimator.
Results
The spontaneous closure rate within the first year of life was 66% (95% CI 58%–73%), increasing to 80% (95% CI 72%–86%) five years after birth. When including both spontaneous closure and closure following treatment, 96% (95% CI 86%–100%) closed within 5 years after birth. The chance of spontaneous closure was reduced in the case of a large patent ductus arteriosus: OR 0.16 (95% CI 0.05–0.52), left atrial enlargement: OR 0.16 (95% CI 0.05–0.51), and pulmonary hypertension: OR 0.23 (95% CI 0.07–0.74).
Conclusion
The chance of spontaneous closure in premature infants born between 23 and 32 weeks of gestation was high, and the incidence continued increasing until 5 years of follow‐up.