Mild Maternal Iron Deficiency Anemia during Pregnancy and Lactation in Guinea Pigs Causes Abnormal Auditory Function in the Offspring

Abstract

Iron deficiency (ID) anemia (IDA) adversely affects different aspects of the nervous system such as myelinogenesis, neurotransmitters synthesis, brain myelin composition, and brain fatty acid and eicosanoid metabolism. Infant neurophysiological outcome in response to maternal IDA is underexplored, especially mild to moderate maternal IDA. Furthermore, most human research has focused on childhood ID rather than prenatal or neonatal ID. Thus, our study evaluated the consequences of mild maternal IDA during pregnancy and lactation on the offsprings' auditory function using the auditory brainstem response (ABR). This technique provides objective measures of auditory acuity, neural transmission times along the peripheral and brainstem portions of the auditory pathway, and postnatal brain maturation. Female guinea pigs (n = 10/group) were fed an iron sufficient diet (ISD) or an iron deficient diet (IDD) (144 and 11.7 mg iron/kg) during their acclimation, gestation, and lactation periods. From postnatal d (PNd) 9 onward, the ISD was given to all weaned offspring. ABR were collected from the offspring on PNd24 using a broad range of stimulus intensities in response to 2, 4, 8, 16, and 32 kHz tone pips. IDA siblings (n = 3), compared with the IS siblings (n = 5), had significantly elevated ABR thresholds (hearing loss) in response to all tone pips. These physiological disturbances were primarily due to a sensorineural hearing loss, as revealed by the ABR's latency-intensity curves. These results indicate that mild maternal IDA during gestation and lactation altered the hearing and nervous system development of the young offspring.