| Value | Category | 
                                    
                    
                        | 1 | contracciones mas de 12 horas | 
                                    
                    
                        | 2 | contracciones menos de 12 horas | 
                                    
                    
                        | 11 | .B | 
                                    
                    
                        | Sysmiss |  | 
                            
            Warning: these figures indicate the number of cases found in the data file. They cannot be interpreted as summary statistics of the population of interest.