Prevalence and associated factors of neonatal microcephaly in Thailand 2014-2018

Abstract

The concern of neonatal microcephaly became high after Zika outbreaks occurred worldwide. Thailand was one of the affected countries. The estimation of neonatal microcephaly prevalence was crucial for public health preparedness and response. The epidemiological characteristics of microcephaly specifically to Thailand were vital to developing clinical management and guideline. The objectives of this study were to estimate the prevalence, describe the epidemiological characteristic and identify associated factors of neonatal microcephaly in Thailand during 2014-2018. This study was a cross-sectional study using data from the health data center, ministry of public health Thailand, 69% of live birth in Thailand was included in this database. Neonatal microcephaly is a newborn who has head circumference (HC) less than the 3rd percentile of standard HC by gestational age (GA) and sex. Univariate and multivariate analyses were performed to identify associated factors by using chi-square and multiple logistic regression, respectively. During 2014-2018, we obtained 121,448 records of a newborn who can evaluate the head size. The prevalence of neonatal microcephaly was 14.5%. Multivariate analysis showed that small for gestational age (SGA) (Adjusted OR 5.34, 95% CI 3.24, 8.81, P-value <0.001), birth length less than the 10th percentile of standard (Adjusted OR 2.92, 95% CI 1.36, 6.29, P-value 0.01), elderly pregnancy (Adjusted OR 1.84, 95% CI 1.07, 3.18, P-value 0.03), and 1st gravida (Adjusted OR 2.01, 95% CI 1.37, 2.95, P-value <0.001) were significantly associated factors of neonatal microcephaly. The prevalence of neonatal microcephaly in Thailand was higher than expected. The international head circumference chart may not suitable for the Thai newborn. The associated factors were birth weight, length, maternal age, and gravida. The standard head circumference for the Thai newborn is needed. The other associated factors may study in the future.