Background:  Iron deficiency anemia (IDA) among preterm infants is a global public health problem due to its effects on development, immunity and general growth that may be irreversible. Preterm infants are 26.4 times more likely to develop IDA compare to term infants. The high prevalence of IDA among preterm infants is associated with low iron stores at birth, rapid catch-up growth, iatrogenic blood loss and limited dietary sources of iron. Despite the high burden of preterm births in Tanzania the prevalence and factors associated with IDA among preterm infants remains relatively understudied and this constituted of the aim of this study. Methods: A cross-sectional analytical study design was conducted among 190 preterm infants who attended premature clinic in Dodoma, Tanzania from December 2022 to May 2023. Socio-demographic, clinical information, and laboratory markers of hemoglobin and iron status were obtained. Descriptive and inferential statistical methods were used for analysis using SPSS version 25. Results: A total of 190 preterm infants were enrolled in the study and the mean age was 4.01 months (SD ±0.99 month). Females were 109, (57.37%). Majority of infants 157, (82.63%) were born as singletons.  Among preterm infants 123 (64.74%) had birth weight of 1.5 kg or more, 175 infants (92.11%) were on iron supplements 45, (9.35%) of preterm infants their mothers had maternal illness and 22, (11.58%) of preterm infants their mothers had severe anemia during pregnancy. The prevalence of IDA among preterm infants was 11.58%. Factors associated with IDA were very low birth weight <1.5 kg), (AOR 6.906, CI: 1.4774-32.359, p value < 0.0142), infants not being on iron supplementation (AOR 6.282, CI:1.045-37.763, p value< 0.0446, multiple pregnancies (AOR 6.848, CI:1.692-27.708, p value <0.0006) severe anaemia during pregnancy (AOR 11.998, CI:5.068-40.197, p value< 0.0001) Conclusion. Iron deficiency anemia is a prevalent in preterm infant. To reduce IDA among preterm infants, there has to be an emphasis on iron supplementation to all preterm infants, and those with very low birth weight, born from mother who had multiple pregnancy and severe anaemia during pregnancy need close follow up and improved postnatal care.

The authors have declared no competing interest.

The author(s) received no specific funding for this work.

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Enrolment was done only after parents/guardians had signed a written informed consent at admission in the neonatal ward. Ethical approval to conduct the study was granted by the University of Dodoma research and ethical review board with ethical clearance reference number MA.84/261/59/154.

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