Anemia is one of the most common conditions in the neonatal period, particularly in premature newborns. It is a pathological condition in which hemoglobin levels are insufficient to meet the body’s physiological needs [1][2]. According to the WHO report, premature births accounted for 13.4 million live births, with nearly 900,000 deaths [3][4]. Deaths related to prematurity are attributable to common complications such as anemia. Little research has been devoted to studying anemia associated with prematurity in our context. The objective of this study was to examine the epidemiological aspects and factors associated with anemia in premature newborns in the Neonatology Department of the Issaka Gazoby Maternity Hospital of Niamey in 2023.

This study, the first of its kind at the Issaka Gazoby maternity hospital in Niamey, highlighted several factors associated with the occurrence of anemia in premature newborns. The limitations or potential biases were also related to the retrospective nature of the study, which reduced the number of variables that could be explored. Furthermore, certain factors traditionally associated with the onset of anemia in premature newborns were not explored in this study. These include the iron status of the mother and newborn, and the measurement of other vitamins and hormones (erythropoietin), which are not feasible in our context.

Anemia in premature newborns is a common condition in the neonatal unit at the Issaka Gazoby Maternity Hospital due to its frequency. Other authors have reported varying frequencies, ranging from 10% to 30% [5][8]-[10]. The differences in rates often depend on the methodologies used, particularly regarding the definition of anemia cases. This high frequency of anemia in premature newborns reflects its multifactorial origin. On the one hand, the immaturity of their hematopoietic organs exposes them to anemia more than full-term newborns. In addition, there is a transient deficiency of erythropoietin, the main hormone involved in hematopoiesis [1]. Apart from these etiological factors, there are hemorrhagic complications that can cause anemia. These include hemorrhagic disease of the newborn, as well as cerebral hemorrhages, particularly intraventricular hemorrhages [4]. Some authors have reported repeated blood sampling for laboratory tests as a risk factor associated with the onset of anemia in newborns [11]. All these factors have led learned societies to recommend preventive measures for anemia in premature newborns. These include systematic iron and multivitamin supplementation and treatment with erythropoietin [7][12][13]. To limit blood loss, it has been recommended to delay cord clamping after delivery and to limit blood sampling [14].

About the characteristics of the mothers, most mothers of newborns with anemia were uneducated. Although this study found no link between maternal education and the occurrence of anemia, it has been shown that educated mothers are more receptive to advice on care and therefore on the prevention of certain risk situations [15]. This study found that 4 or more pregnancy monitoring was associated with a reduced risk of anemia in premature newborns. In general, it is during pregnancy monitoring at PNC that many situations of maternal and neonatal morbidity are detected and managed. These are usually maternal conditions such as nutritional deficiencies, obstetric hemorrhages, and pregnancy-induced toxemia. PNC also provide an opportunity to investigate maternal anemia, which is one of the main causes of anemia and low birth weight. For all these reasons, the WHO now recommends at least one antenatal care visit per month during pregnancy [16].

Antimalarial chemoprophylaxis based on sulfadoxine-pyrimethamine in mothers provides statistically significant protection against anemia in premature newborns. Intermittent preventive treatment is a key intervention during pregnancy to reduce the risk of malaria in pregnant women, and therefore anemia. This treatment is recommended from the onset of active fetal movements until the end of pregnancy in all malaria-endemic countries [17]. Another systematic treatment in our context is iron supplementation. This therapeutic measure compensates for the physiological anemia of pregnant women. During pregnancy, anemia is mainly secondary to increased iron and folic acid requirements, which has led the WHO to recommend this treatment. In addition to its role in hematopoiesis, folic acid is involved in the maturation of the fetal central nervous system [18]. Furthermore, in this study, iron and folic acid supplementation was a statistically significant protective factor against anemia. The type of pregnancy was not associated with the occurrence of anemia in premature newborns in this study. The same results have been reported by other authors in the subregion [8][11][19].

Males were more represented, as found by Lasme et al. and Eyebe et al., without any statistically significant link [8][20]. In contrast, Mah et al. reported a predominance of females, but no link with the occurrence of anemia. In addition, the latter study found a statistically significant risk of death among female newborns (p = 0.002) [19]. The proportion of very low birth weight (less than 1500 g) found in this study was lower than that reported by Dick-Amon F et al. (45%) [5]. Anemia has been reported as a risk factor for low birth weight [12]. In this study, clinical signs were dominated by pallor, respiratory distress, and hypotonia. Lasme Guillao et al. reported pallor (42.7%) as the most common clinical sign, followed by tachypnea (22.5%) and tachycardia (17.7%) [8]. Compared to associated pathologies in newborns, neonatal infection was the most common. Other authors have also found a significant association between infection and anemia, with frequencies ranging from 56.4% to 77% [8][11][21]. Anemia is a common complication of infectious diseases in general due to the acute hemolysis they cause. These infections affect 10% to 30% of premature newborns and are responsible for increased short- and long-term mortality and morbidity [12]. In this study, no statistically significant link was found between deaths in newborns and the presence of anemia, a result corroborated by the study by Koum et al. [21]. Anemia has been described as a major cause of neonatal morbidity and mortality by several authors, suggesting its systematic screening and adequate management [11][19][22].

Anemia in premature infants is a major cause of neonatal morbidity at the Issaka Gazoby Maternity Hospital. The factors associated with the onset of anemia were related to perinatal characteristics, including pregnancy monitoring, iron and folic acid supplementation, and antimalarial chemoprophylaxis based on sulfadoxine-pyrimethamine, suggesting that these strategies should be reinforced. Full-term delivery and hypotrophy also appear to be linked to the occurrence of anemia in premature newborns, hence the need to gain a few weeks before delivery. The aim is to prevent premature delivery and effectively manage associated pathologies in newborns to improve the prognosis.