In 48 cases of primiparae

electronic fetal heart rate monitoring during the course of labor revealed abnormal patterns in 51 cases. These cases were regarded as fetal ditress. the incidence was 9.31%.After 37 weeks of pregnancy

the incidence of abnormal patterns of monitoring increased with gestationai age

during 37-39+6 weeks

40-41+6 weeks and≥42 weeks

the incidence vas 5.3%

10.6% and 23.5% respectively.Abnormal ftal heart rate was discovered by auscultation and heavy meconium-stained amniotic fluid were found in 30(58.8%) of these 51 cases

while no abnormal clinical manfestation was found in 21(41.8%) cases. The frequency of low Apgar scores at on and five minuts was obviously higher in those with abnormal patterns than those with normal patterns The incidence of low one minute score was significantly increased in those with abnormal patterns accompanied by diminished baseline variability.It is believed that iatrapartum electronic fetal heart rate monitoring has a role in early detection of iutrauterinc fetal sphyXia and reduction of perinatal morbidity and mortality.