Jukka Uotila

Objective: This study identifies clinically relevant thresholds for normal and excessive uterine activity (UA) in relation to umbilical artery (UmA) pH. Methods: This blinded secondary analysis included 625 term singleton pregnancies from a randomized controlled trial (NCT02941393, ClinicalTrials.gov ) cohort with intrauterine pressure (IUP) monitoring, cephalic presentation, and umbilical cord blood sampling at birth. Measures included IUP expressed as Montevideo units (MVUs), contraction frequency per 10 min, and uterine baseline tone. Associations between UA and UmA pH (≤7.15) or base excess (linear) were assessed using linear and logistic regression and Student's t ‐test. Results: With an IUP cutoff >250 MVUs, the proportion of neonates with pH ≤7.15 increased from 16.8% to 25.6% (OR 1.68, 95% CI 1.10–2.59; P = 0.017). Among oxytocin‐stimulated labors ( n = 579), an IUP cutoff >200 MVUs was associated with an increase in pH ≤7.15 from 14.7% to 21.4% (OR 1.58, 95% CI 1.02–2.44; P = 0.038). Elevated baseline tone showed a similar association, with the incidence of pH ≤7.15 increasing from 16.6% to 23.6% at a threshold >20 mmHg (OR 1.59, 95% CI 1.06–2.39; P = 0.025). A significant downward shift in UmA pH distribution was observed at a contraction frequency >5/10 min (7.23 [0.09] vs. 7.22 [0.09]; P = 0.042), and among oxytocin‐stimulated labors, this shift occurred already at >4/10 min (7.24 [0.08] vs. 7.23 [0.09]; P = 0.016). Conclusion: Suggested thresholds associated with neonatal acidemia are IUP ≤250 MVUs, contraction frequency ≤5/10 min, and baseline tone ≤20 mmHg. For oxytocin‐stimulated labors, lower thresholds (IUP ≤200 MVUs and contraction frequency ≤4/10 min) appear safer.

Introduction: Sufficient contractions are necessary for a successful delivery but each contraction temporarily constricts the oxygenated blood flow to the fetus. Individual fetal or placental characteristics determine how the fetus can withstand this temporary low oxygen saturation. However, only a few studies have examined the impact of uterine activity on neonatal outcome and even less attention has been paid to parturients’ individual characteristics. Our objective was therefore to find out whether fetuses compromised by maternal or intrapartum risk factors are more vulnerable to excessive uterine activity.Material and methods: Uterine contractile activity was assessed by intrauterine pressure catheters. Women (n = 625) with term singleton pregnancies and fetus in cephalic presentation were included in this secondary, blind analysis of a randomized controlled trial cohort. Intrauterine pressure as Montevideo units (MVU), contraction frequency/10 min and uterine baseline tone were calculated for 4 h prior to birth or the decision to perform cesarean section. Uterine activity in relation to umbilical artery pH linearly or ≤7.10 was used as the primary outcome. Need for operative delivery (either cesarean section or vacuum‐assisted delivery) due to fetal distress was analyzed as a secondary outcome. In addition, belonging to vulnerable subgroups with, for example, chorioamnionitis, hypertensive or diabetic disorders, maternal smoking or neonatal birthweight p < 0.001). Among parturients with suspected chorioamnionitis, every increasing 10 MVUs increased the likelihood of umbilical artery pH ≤7.10 (odds ratio [OR] 1.17, 95% confidence interval [CI] 1.02–1.34, p = 0.023). The need for operative delivery due to fetal distress was increased among all laboring women by every increasing 10 MVUs (OR 1.05, 95% CI 1.01–1.09, p = 0.015). This association with operative deliveries was further increased among parturients with hypertensive disorders (OR 1.23, 95% CI 1.05–1.43, p = 0.009) and among those with diabetic disorders (OR 1.13, 95% CI 1.04–1.28, p = 0.003).Conclusions: Increasing intrauterine pressure impairs umbilical artery pH especially among parturients with suspected chorioamnionitis. Fetuses in pregnancies affected by chorioamnionitis, hypertensive or diabetic disorders are more vulnerable to high intrauterine pressure.

Objective: To investigate whether the use of intrauterine tocodynamometry versus external tocodynamometry (IT versus ET) during labour reduces operative deliveries and improves newborn outcome. As IT provides more accurate information on labour contractions, the hypothesis was that it may more appropriately guide oxytocin use than ET.Design: Randomised controlled trial.Setting: Two labour wards, in a university tertiary hospital and a central hospital.Population: A total of 1504 parturients with singleton pregnancies, gestational age ≥37 weeks and fetus in cephalic position: 269 women with uterine scars, 889 nulliparas and 346 parous women with oxytocin augmentation.Methods: Participants underwent IT (n = 736) or ET (n = 768) during the active first stage of labour.Main outcome measures: Primary outcome: rate of operative deliveries. Secondary outcomes: duration of labour, amount of oxytocin given, adverse neonatal outcomes.Results: Operative delivery rates were 26.9% (IT) and 25.9% (ET) (odds ratio 1.05, 95% CI 0.84–1.32, P = 0.663). The ET to IT conversion rate was 31%. We found no differences in secondary outcomes (IT versus ET). IT reduced oxytocin use during labours with signs of fetal distress, and trial of labour after caesarean section.Conclusions: IT did not reduce the rate of operative deliveries, use of oxytocin, or adverse neonatal outcomes, and it did not shorten labour duration.Tweetable IT (versus ET) reduced oxytocin use in high‐risk labours but did not influence operative delivery rate or adverse neonatal outcomes.

Introduction: Our objective was to compare the efficacy of a 200‐μg misoprostol vaginal insert vs oral misoprostol regarding the cesarean section rate and the time interval to vaginal delivery in nulliparous women with unfavorable cervix.Material and methods: In this prospective multicenter trial, 283 nulliparous women at term with Bishop score P < 0.001), whereas no difference was found in the cesarean section rate (33.8% vs 29.6%, odds ratio [OR] 1.21, 95% confidence interval [CI] 0.66‐1.91, P = 0.67). Other induction methods and labor augmentation with oxytocin and/or amniotomy were less frequent in the misoprostol vaginal insert group (OR 0.32, 95% CI 0.18‐0.59 and OR 0.56, 95% CI 0.32‐0.99, respectively). Need for tocolysis and meconium‐stained amniotic fluid were more common in the misoprostol vaginal insert group (OR 3.63, 95% CI 1.12‐11.79 and OR 2.38, 95% CI 1.32‐4.29, respectively). Maternal and neonatal adverse events did not differ between groups.Conclusions: Misoprostol vaginal insert proved to shorten the time to vaginal delivery and to reduce the use of other methods of labor induction and augmentation, but it did not reduce the cesarean section rate compared with oral misoprostol. The benefit of more rapid delivery associated with misoprostol vaginal insert should be weighed against the greater risks for uterine hyperstimulation and meconium‐stained amniotic fluid.

Background and aim. To compare perinatal outcome in groups of planned vaginal breech delivery, elective cesarean section with the fetus in breech presentation, and planned vaginal delivery with the fetus in cephalic presentation in a university hospital with a tradition of managing breech deliveries by the vaginal route. Methods. A cohort study from a 7-year period 1995–2002, including 590 planned vaginal deliveries with a term (> 37 weeks) singleton fetus in breech presentation, 396 elective cesarean sections with a term singleton fetus in breech presentation, and 590 control women intending vaginal delivery with a singleton term fetus in cephalic presentation. Results. The Apgar scores were lower in the group of planned vaginal breech delivery, but in other outcome measures there were no significant intergroup differences. The overall neonatal morbidity was small (1.2% vs. 0.5% vs. 0.3% in the respective study groups) if compared to a recently published randomized multicenter study. Conclusions. Selective vaginal breech deliveries may be safely undertaken in units having a tradition of vaginal breech deliveries.

The total peroxyl radical-trapping antioxidant parameter (TRAP) of plasma from nine patients suffering from severe preeclampsia was compared with that from nine control patients sharing the same weeks of pregnancy. Measurement of TRAP was by a new chemiluminescent method. The mean TRAP in preeclamptic patients was 1288 ± 110 µmol/l and in control patients 970 ± 153 µmol/l (p<0.001). TRAP was highly correlated with plasma uric acid (r=0.86), and 91% of the increase in TRAP was due to increase in uric acid, which raises a question of the possible antioxidative role of uric acid in preeclampsia.