highly significantp <0.001
Trend of preterm birth From the final set for analyses, (N = 4 392 427), we can observe a highly significant increase (p <0.001) in the rates of PTB by period (Table 2 ).
Trend of preterm birth From the final set for analyses, (N = 4 392 427), we can observe a highly significant increase (p <0.001) in the rates of PTB by period (Table 2 ).