Cardiotocography

Antenatal cardiotocography (CTG) has been widely used for more than 20 years to monitor moderate- to high-risk pregnancies. Observational studies have reported very low rates of perinatal loss in high-risk pregnancies monitored in this way [50,51]. Four randomized controlled trials comparing CTG with other methods of antepartum fetal monitoring were the subject of a Cochrane review [52]. Women with post-term pregnancy were included in these trials. On the basis of the information presented in this review, the antenatal CTG has no significant effect on perinatal outcome or on interventions such as elective delivery. Miyazaki and Miyazaki [53] reported a series of 125 women with post-term pregnancies where a reactive CTG was recorded within 1 week of delivery. Ten adverse outcomes were reported from this group - four antepar-tum deaths, one neonatal death, one case of neonatal encephalopathy and four cases of fetal distress on admission in early labour. The poor performance of antenatal CTG in this series and in the randomized trials may relate to errors in interpretation or excessive intervals between tests. Numerical analysis using computerized calculations of the baseline rate and variability may reduce the potential for human error [54]. Weiner et al. [55] compared the value of antenatal testing with computerized CTG, conventional CTG, Biophysical Profile Scores and Umbilical Artery Doppler. Three hundred and thirty-seven pregnant women who were delivered after 41 weeks' gestation and who had 610 antenatal tests were included in this study. Ten of 12 fetuses with reduced fetal heart rate variation on computerized CTG had a trial of labour. Nine of these 10 fetuses had fetal distress during labour. Seven of the 12 fetuses with reduced fetal heart rate variation were aci-dotic at delivery (umbilical artery pH < 7.2). Overall, there were 10 acidotic fetuses at delivery in the study group. Only two of them had an umbilical systolic/diastolic ratio >95th percentile, three had an amniotic fluid index <5, and five had fetal heart rate decelerations before labour. Fetuses who demonstrated an abnormal intrapartum fetal heart rate tracing or who were acidotic at delivery had a

Table 22.3 Randomized trials of routine versus selective induction at 41-42 weeks' gestation

Gestation at

Table 22.3 Randomized trials of routine versus selective induction at 41-42 weeks' gestation

Gestation at

Trial

Size

trial entry

Method of induction

Method of fetal surveillance

Perinatal deaths

Augensen et al. [90]

4O9

29O

Oxytocin and amniotomy

CTG

0

Bergsjo et al. [74]

188

284

Membrane sweep, oxytocin,

Fetal movement, ultrasound,

1 in induction arm

amniotomy

urinary oestriol

2 in selective arm

Cardozo et al. [75]

363

29O

PGE2, oxytocin, amniotomy

Fetal movement, CTG

1 in selective arm

1 in induction arm

Chanrachakul &

249

29O

Amniotomy and oxytocin

CTG, AFI

0

Herabutya [91]

Dyson et al. [72]

3O2

287

PGE2, oxytocin, amniotomy

CTG, AFI

1 in selective arm

Hannah et al. [70]

34O7

287

PGE2, oxytocin, amniotomy

Fetal movement, CTG, AFI

2 in selective arm

Heden et al. [92]

238

295

Amniotomy, oxytocin

CTG, AFI

0

Henry et al. [73]

112

29O

Amniotomy and oxytocin

Amnioscopy

2 in selective arm

Herabutya et al. [93]

1O8

294

PGE2, oxytocin

CTG

1 in selective arm

James et al. [94]

74

287

Extra-amniotic saline if

Fetal movement, BPS

0

Bishop score <5;

membrane sweep,

amniotomy and

oxytocin

Katz etal. [71]

156

294

Amniotomy, oxytocin

Fetal movement, amnioscopy

1 in each arm

oxytocin challenge

Martin et al. [95]

22

287

Laminaria, oxytocin

CTG, AFI

0

NICHD [96]

44O

287

CTG, oxytocin, amniotomy

CTG, AFI

0

Roach & Rogers [97]

2O1

294

PGE2

CTG, AFI

0

Suikkari et al. [98]

119

29O

Amniotomy, oxytocin

CTG, human placental

0

lactogen, oestriol. AFI

Witter & Weitz [99]

2OO

287

Oxytocin, amniotomy

Oestriol, oxytocin challenge

0

significantly higher rate of reduced fetal heart rate variation or decelerations before labour. The authors conclude that computerized CTG may improve fetal surveillance in post-term pregnancy. The obvious criticism of this study is the 'circular argument' of using an antepartum CTG abnormality to predict an intrapartum CTG abnormality.

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Pregnancy Diet Plan

Pregnancy Diet Plan

The first trimester is very important for the mother and the baby. For most women it is common to find out about their pregnancy after they have missed their menstrual cycle. Since, not all women note their menstrual cycle and dates of intercourse, it may cause slight confusion about the exact date of conception. That is why most women find out that they are pregnant only after one month of pregnancy.

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