Does hypovitaminosis A in mothers cause congenital malformation of eye?

Introduction: Congenital malformation is important cause of child hood blindness, we would like to study factors responsible for it. Methods: This was retrospective cohort study We collected data from our hospital EMR from 2008 to 2019.WE retrieved total number of Pediatric patients outdoor and children with congenital malformed eyes. We also explored history of night blindness in mothers during pregnancy we exported data in excel sheet , type of anomalies calculated using descriptive analyses of SPSS 22. Results: Our cohort consisted of 1435(1.42%) children out of 100946 of total outdoor of pediatric ophthalmology. We found various anomalies in our analyses, out of total 423(29.47%) had history of night blindness to mother during pregnancy suggesting vitamin A deciency. Conclusion: Hypovitaminosis A in mother has inuence maldevelopment and congenital anomalies of eye based on clinical observation.


Introduction
Blindness in children causes a deep impact on the psychological, emotional, and socioeconomic growth of the family. It has been observed that unlike adult blindness, which is 80% avoidable (either preventable or treatable), only less than 50% of the causes are preventable in children. The prevalence globally has been reported to be as high as 1.5 per 1000 children in contrast to the high-income countries where the gure is only 0.3 per 1000 [1,2].
As the prevalence of blindness in children is relatively lower than that in adults, a large sample size is required to provide accurate data on the occurrence and causes of childhood blindness. The current rate is known to be 0.8/1000 [3,4]. The studies from India have shown that there has been an overall increase in congenital globe anomalies over the past two decades, and recent investigations have asserted that the condition contributes to nearly 40% of all causes of Childhood blindness [1,2,3,4]. To tackle the current causes of ocular morbidity attributed to whole globe and retinal abnormalities, a careful genetic counselling of parents before childbirth is necessary.
Treatable refractive error caused 33.3% of the blindness, followed by 16.6% resulting from preventable causes (8.3% each due to vitamin A de ciency and amblyopia after cataract surgery). The other major causes included congenital eye anomalies (16.7%) and retinal degeneration (16.7%) [3].
Upon examining the etiological causes, childhood disorders (mainly corneal infections) as a cause of blindness have declined in the Southern part of the country but are still prevalent in the North and Northeastern parts (especially in the rural pockets) [1,2]. Data also indicate that congenital anomalies and retinal causes are increasing in certain regions of the country [1,2].
However, the etiology is still not known for a majority of the causes (Khanna).

Methods
After obtaining approval from the Hospital Ethical Committee, we retrieved data from the Electronic Medical Records pertaining to the period 2008-2019. All children with congenital malformation were enlisted, and all information regarding the type of anomalies, family history, maternal history, and birth history of the child were acquired. Speci cally, details regarding night blindness in mothers during the last trimester of pregnancy was collected. We documented the total number of fresh outdoor cases, number of children having congenital malformation of the eye, and mothers experiencing night blindness during the last trimester.

Results
Our cohort consisted of 1435 cases. We found that--children were totally examined at the Department of Paediatric Ophthalmology, of which 1435 (%) children exhibited congenital malformation of the eye.  [7].
Horneby asserted the presence of epidemiological and laboratory evidence supporting a hypothesis of genetic (recessive) predisposition to the teratogenic effects of mild-to-moderate maternal vitamin A de ciency during pregnancy. This fact may explain the high prevalence of congenital eye anomalies in certain Asian countries where maternal de ciency of the vitamin is common and consanguineous marriages are popular. Besides, other congenital malformations commonly found in association with ocular coloboma (e.g. Esophageal stulae and heart defects in CHARGE association) might also be related to the de ciency [8].
The results revealed that 43% of the parents were consanguineous, 19% had a positive family history, and that the frequency of coloboma was the highest in the second-born children. Eleven (16%) mothers had a history of night blindness while they were pregnant with the affected child, 7 (8%) had consumed medication during the rst trimester (abortifacients in two cases), 3% had reported fever in the rst trimester, and 11 (13%) had exposure to agricultural chemicals [8].
According to Ward et al., during embryogenesis, information encoded in the genome is translated into cell proliferation, morphogenesis, and early stages of differentiation. Embryonic pattern arises from the spatial and temporal regulation and coordination of these events. The vitamin A (retinol) derivative, retinoic acid (RA), is essential for normal development. Mammalian embryos are protected against vitamin A de ciency by maternal retinoid homeostasis until the stored retinoids fall to very low levels. Retinol binding protein, which is synthesized in the yolk sac placenta of rodent embryos and in the syncytiotrophoblast of the human placenta, is imperative for the embryo to access retinol. Synthesis and metabolism of RA may involve cytoplasmic binding proteins, but the observation that mutants lacking these proteins are normal or near-normal suggests that they are not essential. Severe congenital vitamin A de ciency results in a spectrum of malformations, including defects of the eyes, lungs, cardiovascular system, and urogenital system [9].

Declarations
Ethics and Consent: Patient and parental consent was obtained for minor and approval from hospital ethical committee also was obtained approval no is dn/23/2020