a decreasing trendP < 0.01
From 2010 and 2020, the prevalences of birth defects were 187.28, 227.81, 204.96, 189.61, 221.87, 218.39, 182.03, 179.96, 163.14, 160.34, 164.75 per 10,000 fetuses, respectively, and showed a decreasing trend (χ 2 trend = 246.44, P < 0.01) (Table 1 ).