Year Mean SD No of countries p
1990-1991 290.0 348.3 115 0.008
        (0.038)
1997-1998 195.4 246.2 140 0.58 (significant)
        Not significant difference
2007-2008 212.7 309.8 175 difference
Table 1: Mean and SD of global maternal mortalities among 3 periods. The maternal mortality was significantly decreased between earlier and later periods.