L. F. Goodman1,4, G. Jensen1, T. Nomindelger3, R. Nurjanar2, T. Gantuya3, D. Farmer1 1University Of California – Davis,Surgery,Sacramento, CA, USA 2National Center For Maternal And Child Health,Pediatric General Surgery,Ulaanbaatar, ., Mongolia 3National Center For Maternal And Child Health,Surveillance Department,Ulaanbaatar, ., Mongolia 4Harvard School Of Public Health,Epidemiology,Boston, MA, USA
Introduction: Neonatal mortality in Mongolia declined from 32 per 1000 live births in 1990 to 7.8 per 1000 in 2015. As deaths from infectious disease and birth trauma have been reduced, congenital anomalies have become a relatively more important cause of neonatal mortality. This study sought to determine the prevalence at birth of major congenital anomalies, risk factors associated with anomalies and anomaly-associated neonatal mortality, and the proportion of anomalies that are surgically treatable.
Methods: The National Center for Maternal and Child Health (NCMCH) has maintained an electronic national database of congenital anomalies since 2014, including ICD10 codes, clinical characteristics, risk factors, and reporting physician response to “Treatable with surgery?” The Center for Health Development (CHD) maintains a nation-wide vital registry. Combining the data, we determined the prevalence at birth of major congenital anomalies, with a particular focus on those that are surgically treatable in Mongolia. We also examined risk factors for anomalies and for neonatal death, including infant characteristics, maternal home, and season of birth, among others.
Results: Preliminary analyses of the case series of 1,364 infants in the NCMCH registry suggest prevalence at birth of 8.92 major anomalies per 1000 live births in 2014 (95% CI 7.33-8.55) and 8.87 in 2015 (95% CI 8.24-9.54, birth denominator from CHD). Only 265 (19.4 percent) of infants had anomalies diagnosed in the prenatal period. Of 1,364 infants with major anomalies, 234 or 17.2 percent died within the first 28 days of life. Comparing the 234 neonatal mortality cases to the 1,130 alive at 28 days, there was no significant difference in the gender distribution. The group that died had significantly lower mean birth weight, higher proportion of low and very low birth weight, and lower mean gestational age. A larger proportion of those who died were from rural areas, and a smaller proportion of those who died were considered to be treatable with surgery. A larger proportion of those who died had anomalies diagnosed in the prenatal period.
Conclusion: As expected, the neonates who died were smaller, earlier, and more from rural areas. More of those who died were diagnosed in the prenatal period, though this may reflect more severe anomalies, more easily diagnosed with ultrasound. There are many potentially confounding and effect modifying factors that differ among those who died before 28 days and those who did not. Next steps include determining the prevalence at birth of each ICD10 grouping of anomalies, and carefully controlled regression analyses to determine risk factors for anomalies and anomaly-associated neonatal mortality.
