Intrauterine growth retardation: fluctuation of fetal pH measured between beginning and at the completion of labor

Neonatal morbidity associated with disproportionate intrauterine growth retardation at term

We set out to compare neonatal morbidity between disproportionate intrauterine growth retarded newborn infants and proportionate retarded ones at term, based on ponderal index. This is a prospective study of 185 single pregnancies with evidence of intrauterine growth retardation at term. Sixty three cases (34%) were disproportionate and 122 (66%) proportionate in terms of ponderal index. All were born in the University Hospital 'Principe de Asturias' of Alcala de Henares, Madrid, Spain. Proportionate or disproportionate intrauterine growth retardation diagnosis was established using the ponderal index (weight/length3). The following outcomes of neonatal morbidity were investigated: (1) perinatal asphyxia (meconium-stained amniotic fluid, abnormal fetal heart rates, newborn acidosis or low Apgar score 7 at 5 minutes) and/or (2) early neonatal medical complications. Disproportionate intrauterine growth retardated newborn infants presented higher rates of perinatal asphyxia (54% vs. 32%, P 0.01), with higher abnormal fetal heart rates (37% vs. 15%, P 0.01), higher frequency of arterial pH 7.20 (31% vs. 16%, P 0.05); and also higher rates of early neonatal medical complications (40% vs. 11%, P 0.001), mainly hypoglycaemia (25% vs. 4%, P 0.01). Morbidity among disproportionate intrauterine growth retardated Aconates is significantly higher compared with proportionate ones, demonstrating the heterogeneity of the intrauterine growth retardation population. Proportionate and disproportionate intrauterine growth retardation should be diagnosed as early as possible, since the majority of the morbidity is intimately related to this difference.

Abnormal fetal cerebral and umbilical Doppler measurements in fetuses with intrauterine growth restriction predicts the severity of perinatal morbidity

PURPOSE

This prospective study was performed to determine if the ratio of the middle cerebral artery (MCA) S/D ratio (ratio of peak systolic blood flow velocity to diastolic velocity) to the umbilical artery (UA) S/D ratio (MCA/UA S/D ratio) predicts the degree of neonatal morbidity in fetuses suspected of having intrauterine growth restriction (IUGR).

METHODS

Sixty-one fetuses were identified prospectively by sonography as having an estimated fetal weight below the 10th percentile for gestational age. The 61 fetuses underwent Doppler sonography in the third trimester and then were stratified into 3 groups based on the MCA/UA S/D ratio: group A, MCA/UA S/D ratio > 1.0 (controls; n = 37); group B, MCA/UA S/D ratio < or = 1.0 (intracerebral blood flow redistribution; n = 16); and group C, reversed or absent UA diastolic flow (n = 8). Outcome variables assessed included gestational age at delivery, birth weight, UA pH, mode of delivery, respiratory distress syndrome requiring intubation, and intracranial hemorrhage.

RESULTS

The mean MCA/UA S/D ratios in groups A and B were 1.69 + /- 0.61 and 0.59 + /- 0.24, respectively (p < 0.01). The mean gestational ages at delivery for groups A, B, and C were 34.7, 33.2, and 29.0 weeks, respectively. The mean birth weights were below the fifth percentile for age for groups B and C and significantly related to the severity of abnormal Doppler findings (p < 0.01) after correction for age. Mean UA pHs were 7.25 + /- 0.01, 7.19 + /- 0.01, and 7.14 + /- 0.13 for groups A, B, and C, respectively, with significant differences between groups A and B (p < 0.05) and groups A and C (p < 0.05). Respiratory distress syndrome and intracranial hemorrhage were not associated with abnormal Doppler findings after correction for gestational age. The interval between the abnormal Doppler examination and delivery (p < 0.001) and the occurrence of fetal distress requiring cesarean section (p < 0.001) were significantly related to the severity of Doppler findings.

CONCLUSIONS

In fetuses with suspected IUGR, abnormal MCA/UA S/D ratios are strongly associated with low gestational age at delivery, low birth weight, and low UA pH. Abnormal MCA/UA S/D ratios are also significantly associated with shorter interval to delivery and the need for emergent delivery.

Fetal cardiotocography and acid-base status during cesarean section

OBJECTIVE

To assess the fetal well-being during cesarean section, in relation to the previous fetal condition.

DESIGN

Observational study.

SETTING

University Hospital. PATIENTS PARTICIPANTS: 204 women undergoing cesarean section (203 intrapartum cesarean sections): 177 with general anesthesia and 27 with spinal anesthesia.

MATERIAL AND METHODS

We compared the fetal heart records of the last 30 min before cesarean section (during the first stage of labor) with those during cesarean section. Scalp blood analysis 30 min before the beginning of anesthesia induction was compared with umbilical artery analysis at delivery.

MAIN OUTCOME MEASURES

Cardiotocography. Acid-base analysis. Apgar scores.

RESULTS

During cesarean section there was a reduction in uterine activity, an increase in silent tracings and a decrease in late decelerations. Umbilical artery pH was lower than scalp pH (7.23+/-0.06 vs 7.30+/-0.06). Oxygen saturation was also lower (14.43+/-8.58% vs 18.99+/-8.4%). The values of pCO2 and of base deficit were higher. During cesarean section low values of modified Fischer scores were associated with low pH values of umbilical artery and low Apgar scores.

CONCLUSION

Silent tracings appearing during cesarean section usually do not indicate fetal distress. Poor intracesarean fetal heart tracings were associated with worse indicators of neonatal well-being. Although umbilical pH were lower than scalp values, when the correction described in the literature was applied, the difference was of little clinical relevance. It is concluded that anesthesic, pharmacological and surgical events have slight repercussion in fetal well being. However, in a few cases fetal heart monitoring during cesarean section could detect otherwise undiagnosed cases of transient acidemia or depression in the fetus.