Fig. 2

Prevalence of problematic feeding by gestational age at time of birth. Extremely preterm = < 28 weeks gestation at birth (n = 2503); very preterm = 28–32 weeks gestation at birth (n = 723); moderate to late preterm = 32–37 weeks gestation at birth (n = 1113). Note that Buswell et al. [16] and Hawdon et al. [22] were excluded because they reported on infants across multiple gestational age categories at birth