Objective  To analyze the incidence rate and epidemiological characteristics of birth defects in Liaoning province.

  Methods  We collected and analyzed the surveillance data on all birth defects diagnosed during perinatal period and within one year after birth among all live births and stillbirths in Liaoning province from 2006 through 2015.

  Results  The average incidence rate of birth defect was 205.9/10 000 during the 10-year period in the province. The top 5 birth defects were congenital heart disease, cleft lip and palate, polydactylia, neural tube defects, and congenital hydrocephalus, which together accounting for 51.9% of all the birth defects reported. Of all the birth defects reported, 35.1% were intrauterine stillbirths, stillbirths, infant deaths, and termination of pregnancy. The incidence rate of birth defects was 225.5/10 000 in the male fetuses and infants and significantly higher than that (177.7/10 000) in the female fetuses and infants. The incidence rate of neural tube defects and angioma were higher in the female fetuses than in the male fetuses, but the rate of congenital heart disease, hydrocephalus, hypospadias, cleft lip, and palate were higher in the male fetuses than in the female fetuses. The top ten birth defects differed obviously between perinatal pregnancies and pregnancies less than 28 gestational weeks.

  Conclusion  Congenital heart disease is one of the main defects affecting birth outcomes and population quality in Liaoning province. With the general application of ultrasonic screening and prenatal genetic screening, the incidence of neural tube defects in perinatal period was significantly decreasing. However, there was no significant reduction in the rate of major birth defects during the whole pregnancy.