下面这个列出每个时期的羊水深度正常值，各位孕妈可以对照数据数据参考一下。
孕周均值标准差孕周均值（单位cm）标准差143.310.79153.600.82163.550.63173.930.96184.140.72194.300.68204.550.74214.630.76224.780.75235.090.74245.090.74256.340.80265.420.74275.470.74285.540.82295.500.75305.500.75315.510.66325.480.68335.490.65345.480.67355.400.57365.420.66375.230.66385.110.71394.950.71404.740.54414.650.39
