Dear Editor:

I read with great interest the article by Chen et al. [3]. The authors conducted a study to identify risk factors associated with jaundice in exclusively breastfed term neonates and to guide clinicians regarding the management. The following points need some comment.

The authors found the overall hyperbilirubinemia rate (≥15.0 mg/dl) of 35.3%. This rate is much higher than that described previously, in which the authors found 12% to 13% of breastfed babies with a bilirubin level of ≥12 mg/dl [4, 5]. The possible explanations are as follows. The hyperbilirubinemic group had significantly higher TcB levels at nursery discharge and at OPD follow-up in the present study. Other risk factors for severe hyperbilirubinemia not reported in the present study are: blood group incompatibility, G6PD deficiency, previous sibling received phototherapy, male sex, infant of diabetic mother, East Asian race, etc. [1]. Besides these, supplementary feeding, weight loss percentage, and birth trauma significantly increase the risk of jaundice [2].

The description of length of stay in the nursery not being a major risk factor for hyperbilirubinemia in exclusively breastfed infants might not be true, as the authors have not excluded the above-reported risk factors. The current guideline suggests discharge at any time <72 h significantly increases the risk for readmission to hospital and the risk for readmission with hyperbilirubinemia [1].

The authors also reported that a cesarean section cannot protect breastfed newborn infants from developing hyperbilirubinemia based on their observation. This might be true, as breastfeeding is often delayed in these infants due to the effect of pain and anesthesia in the mother, as well as other comorbidities for which cesarean section was performed.

To conclude, risk factors for jaundice in breastfed infants need to be clearly defined, so that affected infants can be diagnosed early and given timely treatment.