Parental consanguinity increases the risk of congenital malformations

Abstract

Introduction: Congenital malformation is a physical or structural abnormality present either prenatally or after birth. These anomalies are either primary or secondary malformation. Primary malformations adversely affect body functions, however, the secondary malformations are the structural defects which may have less or no effect on body functions. Primary congenital anomalies show marked variations globally with respect to prevalence. The aim of the current study was to further add to the scientific evidences on the pattern and prevalence of congenital anomalies in cousins and non-cousins’ marriages in Khyber Pakhtunkhwa.

Material and Methods: Data of 200 patients (divided into two groups) was collected by convenience sampling through cross-sectional survey. Group-I consisted of 100 gravidas who were diagnosed with anomalous foetus either hydrocephalous, anencephaly or cleft lip/palate and Group-II comprised of infants with inborn heart defects were selected.

Results: The study shows 68% consanguineous and 32% non-consanguineous marriages. Hydrocephalous shows the highest rate of incidence (55%) followed by anencephaly (40%) cleft lip/palate (5%), Ventricular Septal Defect (43%), Atrial Septal Defect (29%), Patent Ductus Arteriosus (16%) and Tetralogy of Fallot (12%). The relative risk of hydrocephalus and anencephaly in consanguineous and non-consanguineous marriage was 0.98 while the relative risk of Ventricular Septal Defect and Patent Ductus Arteriosus was 1.1. Rate of miscarriages was comparatively high in cousin marriages. Frequency of CM was higher in multigravida compared to primigravida. Detection rate of hydrocephalus was highest in second trimester, cleft lip/palate in third trimester and anencephaly in first trimester.

Conclusion: Parental consanguinity is one of the major risk factors for structural, neurological and cardiac anomalies.