Risk factors for meconium aspiration in meconium stained amniotic fluid.

Meconium aspiration syndrome (MAS) is a life-threatening respiratory disease in infants born through meconium stained amniotic fluid (MSAF). The purpose of this study was to determine risk factors for MAS in the newborns of mothers who had meconium stained amniotic fluid in labour. A retrospective study of all full-term pregnancies with MSAF from May 2003 to October 2004 was designed at a teaching hospital. Development of MAS was the primary outcome. Maternal details, mode of delivery and neonatal details (Apgar score, reassuring or non-reassuring fetal heart rate tracing and birth weight) were evaluated. During the study period, there were 2,603 deliveries of whom 302 (11.6%) had MSAF. MAS developed in 64 of these infants (21.1%). Compared with healthy neonates with MSAF, those with MAS had higher rate of non-reassuring fetal heart rate (FHR) tracing, thick meconium and Apgar score < or =5 at 5 min. The neonatal birth weight was lower in the MAS group, maternal age, parity, gestational age and mode of delivery were not significantly different in the two group. We found the severity of meconium, low Apgar score at 5 min and non-reassuring FHR tracing was associated with MAS in MSAF pregnancies.     

Prevention of meconium aspiration

The aim of the study was to determine the risk of meconium aspiration by perinatal and obstetric characteristics and to give directions for prophylactic management. 67 infants with meconium-stained amniotic fluid received intrapartum pharyngeal suctioning and postpartum direct laryngoscopy and suctioning of the trachea. The risk for the presence of meconium in airways is increased if meconium is visible at the vocal cords (p less than 0.01), amniotic fluid showing thick meconium staining (p less than 0.001) Fischer-score being below 7 points (p less than 0.05) or Apgar-score being below 8 points(p less than 0.05).Immediately after delivery inspection of the vocal cords is necessary by direct laryngoscopy. Suctioning of the trachea under direct vision after delivery should be done if meconium is visualized at the vocal cords. Meticulous care of the fetus exposed to a meconium containing amniotic fluid environment and the avoidance of acute fetal stress may decrease the incidence of meconium aspiration.     

Variables associated with meconium aspiration syndrome in labors with thick meconium

OBJECTIVE: To examine the possible maternal and fetal variables associated with meconium aspiration syndrome in labors with thick meconium. STUDY DESIGN: The fetal heart rate tracings, cord pH, Apgar scores and maternal risk factors were evaluated in singleton pregnancies with vertex presentation and thick meconium in labor. The study included 33 consecutive fetuses which developed a moderate or severe meconium aspiration syndrome and 104 consecutive fetuses which had a favorable outcome. RESULTS: Significant differences between fetuses with meconium aspiration syndrome and healthy fetuses were found in the following parameters: baseline FHR (154+/-17 vs. 136+/-10, P<0.0001), small accelerations/30 min (1.47+/-1.52 vs. 3.04+/-1.2, P<0.0001), large accelerations/30 min (1.46+/-1.96 vs. 3.5+/-2.31, P<0.0003), decelerations/30 min (4.9+/-3.9 vs. 2.4+/-2.1, P<0.0034), number of fetuses with reduced beat-to-beat variability (9/33 vs. 0/104, P<0.0001), cord pH (7.21+/-0.09 vs. 7.33+/-0.08, P<0.0013) and Apgar scores at 1 min (5+/-2 vs. 8+/-1, P<0.0001) and Apgar scores at 5 min (8+/-2 vs. 9.7+/-0.6, P<0.0001). Maternal risk factors were found in two of 33 sick infants and in 13 of 104 healthy infants. CONCLUSION: Thick meconium by itself is not associated with adverse fetal outcome. However, the incidence of meconium aspiration syndrome increases in cases of a non-reassuring FHR.     

Simultaneous use of intrapartum fetal pulse oximetry and amnioinfusion in meconium stained amniotic fluid

OBJECTIVE: Fetal pulse oximetry is a minimally invasive, simple technique which continuously helps to reflect in utero well-being. The presence of meconium in the amniotic fluid may be a clinical sign of fetal hypoxaemia. Amnioinfusion has a beneficial effect on the incidence of meconium aspiration syndrome (MAS), and the presence of meconium below the level of the vocal cords. STUDY DESIGN: We studied the impact of amnioinfusion combined with fetal pulse oximetry on the incidence of meconium aspiration syndrome and operative delivery. RESULTS: The retrospective analysis revealed that the presence of meconium below the level of vocal cords was significantly reduced. The frequency of cesarean section is decreased, however, it did not reach statistical significance. CONCLUSION: Fetal pulse oximetry may be used in combination with amnioinfusion and cardiotocography (CTG) to reduce the risk of meconium aspiration syndrome and the number of instrumental deliveries and improve perinatal outcome.     

Labor induction versus expectant management for postterm pregnancies: a systematic review with meta-analysis

OBJECTIVE: To compare routine labor induction with expectant management for patients who reach or exceed 41 weeks' gestation. DATA SOURCES: Computerized databases, references in published studies, and textbook chapters in all languages were used to identify randomized controlled trials (RCTs) evaluating induction and expectant management of labor for postterm pregnancies. METHODS OF STUDY SELECTION: We identified RCTs that compared induction and expectant management for uncomplicated, singleton, live pregnancies of at least 41 weeks' gestation and evaluated at least one of the following: perinatal mortality, mode of delivery, meconium-stained fluid, meconium aspiration syndrome, meconium below the cords, fetal heart rate (FHR) abnormalities during labor, cesarean deliveries for FHR abnormalities, abnormal Apgar scores, and neonatal intensive care unit (NICU) admissions. The primary outcomes assessed were cesarean delivery rate and perinatal mortality. TABULATION, INTEGRATION, AND RESULTS: Sixteen studies met inclusion criteria for this review. For each study with binary outcomes, an odds ratio (OR) with 95% confidence intervals (CIs) was calculated for selected outcomes. Estimates of ORs for dichotomous outcomes were calculated using fixed and random-effects models. Homogeneity was tested across the studies. Compared with women allocated to expectant management, those who underwent labor induction had lower cesarean delivery rates (20.1% versus 22.0%) (OR 0.88; 95% CI 0.78, 0.99). Although subjects whose labor was induced experienced a lower perinatal mortality rate (0.09% versus 0.33%) (OR 0.41; 95% CI 0.14, 1.18), this difference was not statistically significant. Similarly, no significant differences were noted for NICU admission rates, meconium aspiration, meconium below the cords, or abnormal Apgar scores. CONCLUSION: A policy of labor induction at 41 weeks' gestation for otherwise uncomplicated singleton pregnancies reduces cesarean delivery rates without compromising perinatal outcomes.     

A modified fetal heart rate tracing interpretation system for prediction of cesarean section

Objective: To investigate whether a modified version of the 2008 National Institute of Child Health and Human Development (NICHD) interpretation system upon admission decreases cesarean delivery risk. Methods: This retrospective cohort study ascribed a modified category to the first 30?min of fetal heart rate (FHR) tracings in labor. Category I was divided into two subsets (Ia and Ib) by the presence of accelerations. Category II was divided into four subsets (IIa–IId) based on baseline FHR, variability, response to stimulation and decelerations. Log-binomial regression was used to calculate risk ratios (RR) and 95% confidence intervals (CI). Results: A category was ascribed to 910 women. Most FHR tracings were Category Ia (65.8%), Ib (7.7%), IIb (11.8%) and IId (14.0%). Category Ib tracings (fewer than two accelerations) were 2.26 (95% CI: 1.13-4.52) times more likely to result in cesarean delivery for abnormal FHR tracing than Category Ia tracings. A similar increase in risk was seen when comparing Category IIb and Category IId with Category Ia. Conclusion: Application of a modified version of the 2008 NICHD FHR interpretation system to the initial 30?min of labor can identify women at increased risk of cesarean delivery for abnormal FHR tracing.     

Prophylactic amnioinfusion during labor complicated by meconium: a preliminary report

The purpose of this prospective and randomized study is to evaluate the safety and efficacy of prophylactic transcervical amnioinfusion in the management of labor complicated by meconium. A preexisting intrauterine pressure catheter was used for amnioinfusion. The incidence of thick meconium was significantly lower after amnioinfusion, compared with standard management (5% versus 62% p less than 0.0005). This was also demonstrated with spectrophotometry. Significant differences between the amnioinfusion group and the control group were found for the following: arterial cord pH less than 7.20 (16% versus 38%, p less than 0.05); meconium more than trace below the vocal cords at delivery (0% versus 29%, p less than 0.05) and need for positive pressure ventilation at birth (16% versus 48%, p less than 0.05). No complications related to amnioinfusion were observed. We conclude that (1) transcervical amnioinfusion during labor complicated by meconium is a simple and apparently safe procedure, and that (2) amnioinfusion effectively decreases the frequency of thick meconium, the frequency of neonatal acidemia, the frequency of more than trace meconium below the vocal cords, and the need for positive pressure ventilation.     

The effect of meconium on perinatal outcome: a prospective analysis

Objective: To evaluate the effect of meconium-stained amniotic fluid (AF) on perinatal outcome. Methods: A prospective observational study was performed, comparing perinatal outcome of parturients with thick and thin meconium-stained AF to those with clear AF. Results: The rate of meconium-stained AF was 18.1% (106/586). Of those, 78 (13.3%) patients had thin and 28 (4.8%) had thick meconium-stained AF. The rate of oligohydramnios was significantly higher among pregnancies complicated with thick meconium-stained AF (OR 7.2, 95% CI 2.1-24.1; p = 0.002). A significant linear association, using the Mantel-Haenszel test for linearity, was found between the thickness of the meconium and abnormal fetal heart rate patterns during the first and second stages of labor, low Apgar scores at 1 min and the risk for Cesarean section. A statistically significantly higher risk for neonatal intensive care unit admission was observed among patients with thick meconium as compared to those with clear AF (OR 11.4, 95% CI 2.0-59.3; p = 0.006), even after adjustment for oligohydramnios and abnormal fetal heart rate patterns. Conclusions: Thick, and not thin, meconium-stained AF, was associated with an increased risk for perinatal complications during labor and delivery. Therefore, thick meconium-stained AF should be considered a marker for possible fetal compromise, and lead to careful evaluation of fetal well-being.     

Randomised trial of amnioinfusion during labour with meconium stained amniotic fluid

Objective To assess the effect of amnioinfusion during labour with meconium stained amniotic fluid on caesarean section rate and perinatal outcome.
Design Prospective randomised controlled study.
Setting A tertiary care teaching hospital in India.
Population Women in labour at term with meconium stained amniotic fluid.
Methods Two hundred women in labour with ≥37 weeks gestation, single cephalic presentation with moderate or thick meconium were randomised to control and amnioinfusion groups at a 1:1 ratio. Amnioinfusion was performed using 500mL of normal saline over a period of 30 minutes in a study group. The control group received routine care. Both groups had intermittent auscultation of fetal heart rate during labour.
Main outcome measures The primary outcome measure was caesarean section rate. Secondary outcome measures were meconium aspiration syndrome, 1 minute and 5 minute apgar  <7  , hypoxic ischaemic encephalopathy, neonatal intensive care unit admission, meconium at the level of vocal cords.
Results The caesarean section rate in the amnioinfusion group was less than the control group (RR 0.47; 95% CI 0.24–0.93). Amnioinfusion was associated with a significant decrease in the incidence of meconium at the vocal cords (   P = 0.001  ); improvement in 1 minute apgar scores (   P <0.05  ), respiratory distress (   P = 0.002  ) and fewer admissions to nursery compared with the controls. This sample size was inadequate to study the impact on meconium aspiration syndrome.
Conclusion Amnioinfusion in an under resourced labour ward decreases caesarean section rates and fetal morbidity.     

Pregnancy-induced hypertension is an independent risk factor for meconium aspiration syndrome: A retrospective population based cohort study

ObjectiveMeconium aspiration syndrome (MAS), possibly resulting from fetal hypoxia, is a respiratory distress disorder in the infant. Pregnancy-induced hypertension (PIH) can cause placental dysfunction and lead to fetal hypoxia, which may induce the development of MAS. Therefore, the aim of this study was to determine the association between PIH and MAS and to identify the predictive risk factors.Materials and methodsThis was a retrospective cohort study. We selected patients with newly diagnosed PIH and a matched cohort group from the Taiwan National Health Insurance Research Database (NHIRD), from January 1, 2000 till December 31, 2013. For each patient in the PIH cohort, 4 subjects without PIH, matched for age and year of delivery, were randomly selected as the comparison cohort. The incidence of meconium aspiration syndrome was assessed in both groups.ResultsAmong the 23.3 million individuals registered in the NHIRD, 29,013 patients with PIH and 116,052 matched controls were identified. Patients who experienced PIH had a higher incidence of MAS than did those without PIH. According to a multivariate analysis, PIH (odds ratio [OR] = 1.70, 95% confidence interval [CI] = 1.49–1.93, p < 0.0001) was independently associated with increased risk of MAS. Additionally, age ≥30 years (OR = 1.26, 95% CI = 1.12–1.42, p = 0.0001), nulliparity (OR = 1.13, 95% CI = 1.01–1.27, p = 0.0367) and patients with diabetes mellitus (OR = 3.09, 95% CI = 1.35–7.09, p = 0.0078) were also independent risk factors of MAS.ConclusionPatients with PIH obtained higher subsequent risk for the development of MAS than those without PIH. Besides, age ≥30 years, nulliparity and patients with diabetes mellitus are the independent risk factors of developing MAS.     

Intrapartum late deceleration develops more frequently in pre-eclamptic women with severe proteinuria

AIM: Our purpose was to investigate the effect of proteinuria associated with pre-eclampsia on intrapartum fetal heart rate patterns. METHODS: A retrospective study was performed involving 79 pregnant women with pre-eclampsia and 19 pregnant women with gestational hypertension (GH). Pre-eclampsia was then classified into two groups according to the degree of proteinuria (> or = or < 3 + dipstick), which was classified as severe urinary protein (UP; n = 35) and mild UP (n = 44) at delivery. Intrapartum fetal heart rate (FHR) monitoring was classified as either no deceleration, moderate variable deceleration, severe variable deceleration (sVD), prolonged deceleration (PD), occasional deceleration or recurrent late deceleration (rLD). We evaluated the prevalence of non-reassuring FHR (sVD, PD or rLD), the prevalence of intrauterine growth restriction (IUGR), and cord blood gas status in the three groups. The prevalence of non-reassuring FHR and cord blood gas status of these three groups was also compared with their prevalence in 65 women with low-risk pregnancies. Multiple logistic regression analysis was performed to determine the association between rLD and maternal-fetal parameters. RESULTS: Levels of systolic and diastolic blood pressure were similar among the three groups. Severe UP was diagnosed significantly earlier, was associated with significantly lower gestational age, and infants with lighter birth weight (P < 0.05) compared with GH and mild UP. The prevalence of IUGR in severe UP was higher than in GH (54%v. 21%, P < 0.05); however, no differences were found in the prevalence of IUGR between mild and severe UP (43%v. 54%, P = 0.33). The prevalence of non-reassuring FHR in GH was not statistically significant in the low-risk pregnancies (5%v. 9%, P = 0.58). In mild and severe UP, the non-reassuring FHRs were more predominant (30% and 43%, respectively) than in low-risk pregnancies and GH (P < 0.05). The rLD was more common in the group with severe UP and accounted for 40% of all FHR patterns. There was no difference in the incidence of low pH among the groups. However, fetuses in pregnancies involving severe UP were significantly hypoxemic when compared with others. Multiple logistic regression analysis showed that worsening proteinuria (odds ratio [OR], 5.5; 95% confidence interval [CI], 2.4-12.9) and IUGR (OR, 3.8; 95% CI, 1.2-11.5) increased the risk of rLD. Rates of preterm birth at less than 32 weeks (OR, 0.7; 95% CI, 0.2-2.5) and severe hypertension (OR, 0.5; 95% CI, 0.2-1.3) were not significant. CONCLUSION: In pre-eclampsia, the presence of severe proteinuria is associated with an increased likelihood of rLD.     

Intrapartum amnioinfusion for meconium-stained amniotic fluid: a systematic review of randomised controlled trials

BACKGROUND: Amnioinfusion (AI) is thought to dilute meconium when present in the amniotic fluid and so reduces the risk of meconium aspiration. OBJECTIVES: To evaluate if AI reduces meconium aspiration syndrome (MAS) and other indicators of morbidity in babies born to women with meconium-stained amniotic fluid (MSAF). SEARCH STRATEGY: PubMed, Medline, EMBASE, and the Cochrane Controlled Trials Register from January 1980 to May 30, 2005, using the keywords 'amnioinfusion' and 'meconium'. SELECTION CRITERIA: Randomised trials comparing AI with no AI for women in labour with MSAF. Trial quality was evaluated using pre-established criteria. DATA COLLECTION AND ANALYSIS: The following morbidity indicators were assessed: MAS, 5-minute Apgar score < 7, arterial cord pH < 7.2, and caesarean section. Studies were stratified according to the level of peripartum surveillance (standard versus limited). Typical relative risks (RRs) with their 95% confidence intervals were calculated for each outcome using a random effects model. MAIN RESULTS: In clinical settings with standard peripartum surveillance, we found no evidence that AI reduced the risk of MAS (RR 0.59, 95% CI 0.28-1.25), 5-minute Apgar score < 7 (RR 0.90, 95% CI 0.58-1.41), or caesarean delivery (RR 0.89, 95% CI 0.73-1.10). In clinical settings with limited peripartum surveillance, AI appeared to reduce the risk of MAS (RR 0.25, 95% CI 0.13-0.47). CONCLUSION: In clinical settings with standard peripartum surveillance, the evidence does not support the use of AI for MSAF. In settings with limited peripartum surveillance, where complications of MSAF are common, AI appears to reduce the risk of MAS. However, this finding requires confirmation by further studies.     

Delivery room risk factors for meconium aspiration syndrome

The objective of this study is to identify risk factors for meconium aspiration syndrome (MAS) in newborns born through meconium-stained amniotic fluid (MSAF). From May 27, 1994 to June 9, 1997 maternal and neonatal data were prospectively collected on all infants born through MSAF. Development of MAS was the primary outcome. Using bivariate and logistic regression analysis we identified risk factors for MAS. There were 8,967 births during this period: 7.9% (708 of 8,967) were delivered through MSAF. Respiratory symptoms developed in 6.8% (48 of 708) of births. Of these, 50% (24 of 48) were excluded due to the diagnosis of transient tachypnea of the newborn (17), respiratory distress syndrome (4), group B streptococcus pneumonia (1), congenital cytomegalic inclusion disease (1), and supraventricular tachycardia (1). Of the 24 infants with respiratory symptoms consistent with MAS, 45.8% (11 of 24) required ventilatory support, one required extracorporeal-membrane oxygenation. Bivariate analysis identified six risk factors ( p <0.05): Apgar <7 at 1 minute, Apgar <7 at 5 minutes, thick meconium, fetal distress, suction of infant's stomach by delivery room team at <5 minutes of age, and need for resuscitation. Tracheal meconium was very prevalent in our population at 74% of all intubated infants, and was not significantly associated with MAS. Logistic regression analysis identified four independent risk factors. Looking at multiple prediction models, an infant with fetal distress, Apgar <7 at 1 and 5 minutes and thick meconium has a 79.8% probability of developing respiratory symptoms. If these risk factors are not present, there is a 0.8% risk. In our cohort, this group had 16.7% positive predictive value (4 of 24) and 99.6% negative predictive value (657 of 660). In meconium deliveries, infants with thick meconium, fetal distress, and Apgar scores <7 at 1 and 5 minutes are at high risk for development of respiratory symptoms. Infants delivered in the absence of all of these risk factors are at low risk for development of MAS.     

In utero meconium suctioning may prevent meconium aspiration

OBJECTIVE: To assess usefulness of in utero meconium suctioning using endoscopic approach. Materials and METHODS: In utero meconium suctioning under direct endoscopic visualization was successfully performed in 11 fetuses in whom thick meconium was detected upon rupture of the membranes. A gas-sterilized flexible fiberoptic scope with an operational channel was introduced via cervix, and meconium was aspirated from the fetal mouth. Definitive suction was performed in all neonates immediately after birth. RESULTS: Endoscopic meconium suctioning was successfully performed in 11 out of 16 fetuses with retrieval of 3-12 ml of meconium. Only 1 neonate in this series of cases had meconium below the vocal cords and none developed meconium aspiration syndrome postnatally. CONCLUSION: Because fatal meconium aspiration syndrome is largely an intrauterine event, the concept of in utero prophylactic meconium suctioning may serve as an effective modality for its prevention.     

Impact of fetal blood sampling on vaginal delivery and neonatal outcome in deliveries complicated by pathologic fetal heart rate: a population based cohort study

OBJECTIVE: To compare the impact of electronic fetal monitoring (EFM) alone vs. EFM with additional fetal blood sampling (FBS) in vaginal deliveries complicated by pathologic fetal heart rate (FHR). METHODS: All deliveries in Hesse between 1990 and 2000 were evaluated for participation in this study. Inclusion criteria comprised (1) pathologic fetal heart rate, (2) singleton pregnancy, (3) cephalic presentation, (4) vaginal delivery, and (5) gestational age at delivery of more than 35 weeks' gestation. In order to analyze the meaning of additional risk factors at birth for the effectiveness of FBS two subgroups were selected depending on the presence of additional risk factors at birth. To examine the impact of FBS in deliveries with pathologic FHR on the mode of delivery and on neonatal outcome, univariate regression analysis was performed and odds ratios (OR) and their corresponding 95% confidence intervals (95% CI) were calculated. RESULTS: The study population comprised 49,560 deliveries, among deliveries complicated by pathologic FHR, 26% underwent FBS. Deliveries with pathologic FHR and controlled by FBS, with no additional antepartum risk factors, were associated with an increase in spontaneous births OR 1.41 (95% CI 1.27-1.58), and in the presence of additional risk factors OR 1.24 (1.19-1.30). Short-term neonatal outcome parameters were characterized by a lower frequency of severe fetal acidosis (umbilical artery pH <7.0) OR 0.55 (0.42-0.72), and Apgar score <5 after 5 min, OR 0.71 (0.55-0.90). CONCLUSION: In vaginal deliveries with pathologic FHR the use of FBS as an additional means of intrapartum fetal surveillance is associated with less vaginal operative deliveries, and with an improved short-term neonatal outcome.     

Meconium-stained amniotic fluid in labor: a randomized trial of prophylactic amniofusion

OBJECTIVES: To investigate the effect of amnioinfusion in women with meconium-stained amniotic fluid on the rate of cesarian sections and on neonatal morbidity. STUDY DESIGN: A randomized controlled trial. A total of 206 women with meconium-stained amniotic fluid were assigned to receive amnioinfusion via two-way catheter or no amnioinfusion (control group). The catheter was inserted and other treatment was the same in both groups. RESULTS: Amnioinfusion decreased the rate of cesarian sections for fetal distress (RR 0.23, 95% CI 0.07-0.79) and increased mean pH at birth (7.24+/-0.1 versus 7.21+/-0.1, P<0.05). It also decreased the frequency of variable fetal heart rate decelerations (RR 0.74, 95% CI 0.59-0.92), and of meconium below the vocal cords in neonates (RR 0.37, 95% CI 0.19-0.69). CONCLUSIONS: Amnioinfusion improves the neonatal outcome and reduces the frequency of cesarian sections.     

The influence of maternal epidural analgesia upon intrapartum fetal oxygenation.

OBJECTIVE: The use of maternal epidural analgesia in labor may be associated with non-reassuring fetal heart rate (FHR) patterns. We aimed to assess changes in fetal oxygen saturation (FSpO(2)) during epidural analgesia in labor. METHODS: This was a prospective observational study. Twenty healthy parturients were enrolled following the inclusion criteria. Informed consent was obtained. Mode of delivery, use of oxytocin, maternal blood pressure, umbilical cord blood analysis, Apgar score, and neonatal outcomes were evaluated. Ropivacaine at a low concentration of 0.1% (1 mg/mL) co-administered with an opioid (fentanyl 2.5 microg/mL) was used. The values of fetal oxygen saturation were registered continuously 10 minutes before the administration of the analgesic drug and during the following 30 minutes after administration. Pulse oximetry was used simultaneously with cardiotocography (CTG). RESULTS: The average value for fetal oxygen saturation before the analgesic drug administration was 44.3 +/- 8.8%; during the first 10 minutes following administration it was 41.3 +/- 7.2% (p = 0.25) and during the following 20 minutes it was 43.05% +/- 6.9% (p = 0.63). There was no direct relationship between non-reassuring CTG pattern appearance and FSpO(2) <30% (RR = 1.11, 95% CI 0.76-1.64). No significant correlation was found between FSpO(2) values within the first 30 minutes of epidural analgesia and neonatal acidotic status (pH or=30%.     

Is meconium passage a risk factor for maternal infection in term pregnancies?

OBJECTIVE:To study the association between meconium and maternal infection. METHODS:This was a retrospective cohort study of 678 pregnant women. All term deliveries during a 31-month period with meconium passage were included. Each meconium delivery was matched with a consecutive delivery without meconium at the same gestational age. RESULTS: The overall infection rate was 16%, with 13% of the infections directly related to the pregnancy, labor, and delivery. The endometritis rate was 5%, with 7.1% and 3% in the meconium and no-meconium group, respectively. The chorioamnionitis rate was 8.3%, with 9.5% in the meconium and 7.1% in the no-meconium group. Factors found to be associated with overall obstetric infections had the following odds ratios (ORs) and 95% confidence intervals (CIs): meconium (OR 1.8, 95% CI 1.1, 2.8), internal monitoring (OR 3.4, 95% CI 1.9, 5.9), amnioinfusion (OR 2.0, 95% CI 1.3, 3.3), number of vaginal exams (OR 4.5, 95% CI 2.8, 7.1), length of labor (OR 2.8, 95% CI 1.8, 4.4), and cesarean (OR 3.1, 95% CI 1.9, 5.1). Logistic regression analyses revealed the following ORs and 95% CIs: 1) for endometritis-cesarean (OR 4.2, 95% CI 1.9, 8.9), internal monitoring (OR 2.5, 95% CI 1.1, 5.9), and meconium (OR 2.5, 95% CI 1.1, 5.5), and 2) for chorioamnionitis-length of labor greater than 10 hours (OR 2.7, 95% CI 1.4, 5.6), number of vaginal exams greater than seven (OR 3.4, 95% CI 1.7, 6.6), and use of internal monitors (OR 2.5, 95% CI 1.2, 5.3). CONCLUSION: Meconium passage increases the risk of postpartum endometritis but not chorioamnionitis. Length of labor, internal monitoring, and number of vaginal exams are risk factors for chorioamnionitis.     

Changes in fetal heart rate and uterine patterns associated with uterine rupture

OBJECTIVE: To determine changes in fetal heart rate (FHR) and uterine patterns preceding complete uterine rupture. STUDY DESIGN: FHR and uterine patterns of 50 women with uterine rupture were compared with 601 tracings of controls without scarred uteri. Tracings were interpreted using the National Institute of Child Health and Human Development Research Planning Workshop guidelines. RESULTS: Interobserver and intraobserver agreements of FHR and uterine tracings in the uterine rupture group were excellent (kappa of .96 for both variables). Comparing tracing patterns during the first stage, higher rates of severe fetal bradycardia (4.0% vs. 1.0%, P = .064), fetal tachycardia (8.0% vs. 2.3%, P = .042), reduced baseline variability (24.0% vs. 12.5%, P = .021), uterine tachysystole (10.0% vs. 0.8%, P < .001) and disappearance of contractions (6.0% vs. 0, P < .001) were noted among patients with uterine rupture as compared to the controls. During the second stage of labor, patients with uterine rupture had significantly higher rates of reduced baseline variability (47.8% vs. 7.7%, P < .001), severe variable decelerations (26.1% vs. 6.4%, P = .004), uterine tachysystole (22.0% vs. 0.5%, P < .001) and disappearance of contractions (13.0% vs. 0, P < .001). Using a backward, stepwise multiple logistic regression model, severe fetal bradycardia (OR = 8.2, 95% CI 2.2-31.0, P = .002) and uterine tachysystole (OR = should alert the 8.0, 95% CI 1.7-37.9, P = .008) were found to be independent patterns preceding uterine rupture during the first stage of labor. Likewise, during the second stage, reduced baseline variability (OR = 4.2, 95% CI 1.4-12.3, P = .009) and uterine tachysystole (OR = 42.3, 95% CI 10.6-168.3, P < .001) were independently associated with uterine rupture in another multivariable analysis. CONCLUSION: Abnormal monitor patterns among women presenting with risk factors for uterine rupture, specifically uterine tachysystole, reduced baseline variability and severe bradycardia, should act as warning signs to the obstetrician.