Main baseline characteristics of patients , including age ( 36.1 4.5 vs 35.7 5.8 ) , body mass index ( 34.9 5.1 vs 35.1 4.9 kg/m ( 2 ) ) , and parity ( 2.1 0.4 vs 1.9 0.9 ) , were not significantly different between the DOE and OHT groups ( P > .05 ) .