Background: Low birth weight (LBW) infants are at high risk of zinc deficiency, but there is a paucity of data on their zinc status. Objective: To evaluate zinc status of LBW (BW <2,500 g) and normal birth weight (NBW; BW ≥2,500 g) infants at birth and in early infancy. Methods: A total of 339 infants (LBW, n = 220; NBW, n = 119) were enrolled, and venous blood samples of mother-infant dyad were taken within 48 h of birth. Infants’ levels were repeated between 2 and 10 months of age. Serum zinc levels were estimated using an inductively coupled plasma mass spectrometer. Primary outcome was zinc deficiency, defined as serum zinc <65 µg/dl. Results: Zinc results were available for 182 LBW and 103 NBW infants at birth and for 100 LBW and 66 NBW infants at follow-up with a median postnatal age of 14 and 15.5 weeks, respectively. Median zinc levels were low and comparable at birth as well as at follow-up, with zinc deficiency being present in 51.0% of LBW and 42.4% of NBW infants at birth and in 79.0% of LBW and 66.7% of NBW infants at follow-up. Zinc levels decreased significantly in both groups from birth to follow-up, irrespective of zinc multivitamin supplementation. Zinc levels of infants with BW <2,000 g at follow-up were significantly lower compared to infants with higher BW. Conclusion: Zinc status was poor in many infants at birth irrespective of BW. Zinc status worsened significantly during early infancy, with infants with BW <2,000 g having the lowest zinc levels.

High prevalence of VDD in LBW as well as NBW infants with clinical rickets at an early age underlines the need to study the effect of various vitamin D supplementation regimens in these infants to identify the optimal dose.

Serum retinol levels of low birth weight (LBW; birth weight < 2500 g) and normal birth weight (NBW; birth weight ≥ 2500 g) infants were evaluated at birth and 3 months using high performance liquid chromatography. At birth, levels were 13.3 ± 8.2 ug/dL in LBW (n=146) and 14.0 ± 6.2 ug/dL in NBW infants (n = 79; p = 0.51), with 41.1% of LBW and 24.1% of NBW infants having vitamin A deficiency (VAD, < 10 ug/dL; P = 0.01). At follow up, levels were 18.0 ± 9.4 ug/dL in LBW (n = 83) and 20.0 ± 7.3 ug/dL in NBW infants (n = 51; P = 0.19), with 18.1% of LBW and 3.9% of NBW infants having VAD (P = 0.02).

Serum ferritin levels of low birth weight (LBW; BW < 2,500 g) and normal birth weight (NBW; BW ≥ 2,500 g) infants were evaluated at birth and at 3 mo using electrochemiluminescence immunoassay. At birth, levels were 318.6 (31.0-829.5) ng/mL in LBW (n = 217) and 366.2 (122.4-858.5) ng/mL in NBW infants (n = 116; p < 0.01), with 1.4 % of LBW and none of the NBW infants having levels <12 ng/mL (p = 0.20). At follow up, levels were 66.9 (4.5-567.7) ng/mL in LBW (n = 126) and 126.2 (6.8-553.7) ng/mL in NBW infants (n = 76; p = 0.27), with 11.9 % of LBW and 11.8 % of NBW infants having levels <12 ng/mL (p = 0.80).