Latent Iron Deficiency at Birth Influences Auditory Neural Maturation in Late Preterm and Term Infants
Condition: Latent Iron Deficiency at Birth
MeSH terms: Anemia, Iron-Deficiency; Iron Deficiencies
Study type: Observational

Summary: 
      This study evaluates auditory neural maturation by auditory brainstem evoked response in late
      preterm and term infants with in utero iron deficiency compared with neonates with normal in
      utero iron status.
    

Detailed description: 
      Iron is an essential nutrient for brain development. During early human development, iron is
      required for multiple neurodevelopmental processes. To meet the iron requirements of a
      developing brain, active transfer of iron occurs across the placenta during the last
      trimester of pregnancy and therefore most term infants have iron replete status at birth.
      However, maternal iron deficiency during pregnancy, a global health problem, can negatively
      affect the fetal iron status. In addition, prematurity, maternal diabetes mellitus,
      preeclampsia, maternal smoking, and intrauterine growth restriction during pregnancy have
      also been associated with decreased iron transfer to the fetus often leading to in utero iron
      deficiency.

      Cord serum ferritin (SF) level at birth provides a good measurement of fetal tissue iron
      storage concentration and is therefore often used to evaluate in utero iron status. The
      absolute and interpeak latencies on auditory brainstem evoked response (ABR) are often used
      as surrogate outcome measures for neural maturation in the neonates. The absolute latencies
      for each of these ABR waves and the interpeak latencies (IPL, I-III, III-V, and I-V) are
      influenced by the degree of myelination, neuronal development, synaptic function, and axonal
      growth in the auditory nervous system. The absolute latencies and IPL decrease as the
      auditory neural system matures with age in neonates.

      Although iron is essential for auditory neural maturation during the perinatal period, there
      is a paucity of data regarding the concomitant effect of in utero iron deficiency on auditory
      neural maturation in late preterm and term infants. The present prospective study is planned
      with an objective to determine the association of in utero iron deficiency as evaluated by
      cord ferritin with auditory neural maturation at birth in ≥ 34 weeks GA infants.
    

Intervention name(s): Auditory brainstem evoked response (ABR)
Intervention type(s): Device
Intervention description(s): Bilateral monaural auditory brainstem response (ABR) test would be recorded in each subject with a Bio-logic Navigator Evoked Response System (Bio-logic Systems, USA) between 24 and 48 hours after birth by an audiologist skilled in administering ABR to newborn infants. ABRs shall be performed using 80 dB nHL broadband click stimuli with insert earphones and with the subject lying supine in a quiet room and normal skin temperature. The clicks would be presented at a repetition rate of 29.9/second, and three runs of 2000 repetitions to be recorded for each ear. The 2 most replicable runs for each ear shall be averaged and used for analysis. Absolute latencies of waves I, III, V and IPL (I-III, III-V, and I-V) shall be measured and considered outcomes
Observational model: Cohort
Time perspective: Prospective
Sampling method: Non-Probability Sample
Study population: 
        All neonates born between 34 - 42 weeks of gestation at Sir Ganga Ram Hospital during study
        period would be evaluated for enrolment in the study till 30 neonates each enrolled in the
        three groups: appropiate for gestational age, small for gestational age, infants of
        diabetic mother.