Risk Of Meconium Aspiration Syndrome Research Articles

Frequency of PPHN in Neonates Having Confirmed Diagnosis of Meconium Aspiration Syndrome

Background: Optimal oxygenation, avoidance of respiratory and metabolic acidosis, normal blood pressure, sedation & pulmonary vasodilator treatment are among the management techniques for persistent pulmonary1hypertension of the newborn. Aim: To find frequency of PPHN in neonates having confirmed diagnosis of meconium aspiration syndrome. Study Design: Descriptive cross sectional study. Methodology: Total 240 neonates who fulfilled inclusion criteria were enrolled from Pediatrics Medicine Ittifaq hospital Lahore after getting informed consent form parents or attendants. Basic information like gestational age, gender, birth weight, APGAR score at 7 minutes, mode of delivery were taken (on antenatal record). All cases with confirmed diagnosis of MAS were underwent 2D Echocardiography and PPHN were diagnosed as per operational definition. All diagnostic procedure was done by a single consultant cardiologists. SPSS 20.0 was utilized to analyze the data. For quantitative data, mean and standard deviation were provided, while frequencies and percentages were provided for qualitative factors. Post stratification Chi-square test was applied taking p-value ≤ 0.05 as significant. Results: The mean birth weight was 3211.02±412.10 grams with min & max birth weight as 2500 and 3882 g. The mean APGAR score was 7.95±1.41. There were 85(35.4%) cases who had PPHN while 155(64.6%) cases did not have positive diagnosis of PPHN. Conclusions: It was concluded that frequency of PPHN in neonates having confirmed diagnosis of meconium aspiration syndrome is very high. So early screening during antenatal visits and adopting preventive strategies can only minimize the risk of meconium aspiration syndrome thus preventing PPHN. Keywords: Persistent Pulmonary Hypertension, Meconium Aspiration Syndrome, Meconium Stained Amniotic Fluid

Assessment of Change in Practice of Routine Tracheal Suctioning Approach of Non-Vigorous Infants Born through Meconium-Stained Amniotic Fluid: A Pragmatic Systematic Review and Meta-Analysis of Evidence outside Randomized Trials

Aim: The 2015 recommendation of the International Liaison Committee on Resuscitation of no routine tracheal suctioning in non-vigorous neonates born through meconium-stained amniotic fluid (MSAF) was based on very low certainty of evidence (CoE) necessitating ongoing monitoring. The aim of this systematic review was to perform a meta-analysis of observational studies comparing the effect of implementing immediate resuscitation without routine tracheal suctioning versus with routine suctioning in neonates born through MSAF. Methods: MEDLINE, Embase, CENTRAL, and Web of Science were searched. Observational studies with a before-and-after design were included. Two authors extracted data independently. CoE based on GRADE recommendations was performed. Results: 13 studies were included. Clinical benefit or harm could not be excluded for the composite primary outcome of mortality or requirement of extracorporeal membranous oxygenation (ECMO) (relative risk, 95% confidence interval: 0.74 [0.47–1.17]), and mortality (0.68 [0.42–1.11]). “Routine tracheal suctioning” epoch had possibly lesser risk of meconium aspiration syndrome (MAS) when compared to “no routine tracheal suctioning” epoch (0.68 [0.47–0.99]). “Routine tracheal suctioning” epoch also possibly had a lower risk of hospital admission for respiratory symptoms, requirement of non-invasive respiratory support, invasive mechanical ventilation, surfactant treatment, air leak, and low-flow oxygen therapy. Clinical benefit or harm could not be excluded for the outcome of mortality or ECMO among those diagnosed with MAS (1.09 [0.86–1.39]), but “routine tracheal suctioning” was possibly associated with lower risk of respiratory morbidities among those diagnosed with MAS. The CoE was very low for most of the outcomes evaluated. Conclusions: Due to the very low CoE for the outcomes evaluated, no definitive conclusions can be drawn warranting the need for additional studies.

Determinants of meconium aspiration syndrome among neonates admitted to neonatal intensive care unit at Nigist Eleni Mohammed Memorial Comprehensive Specialized Hospital, South Ethiopia: Unmatched case-control study.

Objective:To identify determinants of meconium aspiration syndrome among neonates admitted to the neonatal intensive care unit at Nigist Eleni Mohammed Memorial Comprehensive Specialized Hospital, South Ethiopia, in 2022.Method:A facility-based unmatched case–control study was used to identify meconium aspiration syndrome with a total sample size of 249 from January to April 2022. Data were entered by using EpiData version 3.1 and analyzed using SPSS version 24 software. Descriptive findings were presented by frequency tables and percentages. Multicollinearity was checked and the goodness of fit test was done. To determine the independent determinants associated with meconium aspiration syndrome, bivariate analysis was done and variables with a p value of <0.05 were taken to multivariate logistic regression analysis. Adjusted odds ratio with a 95% confidence interval was calculated, and statistical significance was declared at a p value less than 0.05.Result:Two hundred forty-nine (83 cases and 166 controls) mothers with their respective neonates were included in this study and that made the overall response rate 100%. Preeclampsia (adjusted odds ratio: 3.35, 95% confidence interval: 1.02, 10.97), antepartum hemorrhage (adjusted odds ratio: 3.63, 95% confidence interval: 1.50, 8.78), duration of labor (adjusted odds ratio: 4.34, 95% confidence interval: 1.83, 10.30), premature rupture of membrane (adjusted odds ratio: 16.02, 95% confidence interval: 5.66, 45.29), and obstructed labor (adjusted odds ratio: 4.57, 95% confidence interval: 1.42, 14.70) were determinants of meconium aspiration syndrome.Conclusion:In this study, preeclampsia, antepartum hemorrhage, duration of labor, premature rupture of membrane, and obstructed labor were determinants of meconium aspiration syndrome. Therefore, to reduce the risk of meconium aspiration syndrome, prevention, early identification, and management of these obstetrical factors may help to reduce meconium aspiration syndrome locally.

Optimal delivery timing for twin pregnancies: A population-based retrospective cohort study.

The optimal timing of delivery for twin pregnancies remains controversial. This study examined the risks of adverse neonatal outcomes and neonatal deaths according to gestational age at delivery in order to determine the optimal gestational age of delivery for twin pregnancies. This is a retrospective study of twin pregnancies delivered between 34 and 40weeks of gestation from 1995 to 2000 in the United States. The primary outcomes evaluated were neonatal morbidity and mortality. The composite outcome of neonatal morbidity included the following variables: Apgar score lower than 7 at 5minutes, assisted ventilation <30minutes, assisted ventilation ≥30minutes, hyaline membrane disease, meconium aspiration syndrome, neonatal seizures, birth injury, anaemia, and congenital malformations. Logistic regressions were applied to calculate adjusted odds ratios of the adverse outcomes according to the gestational week at delivery, with either individual twins or twin pairs as the unit of analysis. A total of 466038 twins from 233019 pregnancies from the US National Center for Health Statistics matched the multiple birth data set included in the study. The composite neonatal morbidity and mortality risks declined from 34 to 38weeks of gestation and increased thereafter in both individual and pair twins stratified analyses. Amongst neonatal adverse outcomes, the risk of low Apgar score and hyaline membrane disease decreased progressively towards 38weeks of gestation, only to increase again towards 40weeks. The risk of meconium aspiration syndrome increased after 38weeks, in both individual and pair twins. There were no differences in the risk of birth injury and neonatal seizures when stratified by gestational age. The optimal timing for twin delivery appears to be at 38weeks of gestation, although individual maternal, foetal, and pregnancy characteristics should be considered when determining the best timing for delivery.

The risk of meconium aspiration syndrome (MAS) increases with gestational age at term

Objective To examine the risk of meconium aspiration syndrome (MAS) by the week of gestational age in pregnancies with meconium-stained amniotic fluid (MSAF). Methods This is a retrospective cohort study derived from term pregnancies at a single tertiary institution over an 18-year period. Outcomes analyzed included MAS, acidemia, and Apgar scores. Univariate analysis was performed using chi-square and multivariable logistic regression was used to adjust for potential confounders. Results A total of 34,303 deliveries ≥37 weeks were included; 23.7% were complicated by MSAF. Of the total study cohort, 272 (0.7%) neonates were diagnosed with MAS; this represented 3% of all deliveries complicated by MSAF. In the presence of MSAF, the risk of MAS increased with gestational age, from 1.3% at 38 weeks to 4.8% at 42 weeks (p < .001). Similarly, the risk of acidemia increased from 3.0% at 38 weeks to 7.0% at 42 weeks (p < .001). These findings were also demonstrated in patients with MAS in the absence of MSAF. The risk for both MAS and acidemia in the presence of MSAF persisted after controlling for potential confounders (aOR 1.31 [95% CI 1.18–1.46] and 1.20 [95% CI 1.05–1.37], respectively). Conclusion In women with MSAF, as gestational age increases, the risk of meconium aspiration syndrome also increases. Other factors with late-term and post-term pregnancy besides the presence of meconium may contribute to the evolution of MAS.

Propensity score method for analyzing the effect of labor induction in prolonged pregnancy.

There is an ongoing debate on the optimal time of labor induction to reduce the risks associated with prolonged pregnancy. Registry-based study of 212716 term, singleton cephalic deliveries between 2006 and 2012 in Finland comparing the outcomes of labor induction with those of expectant management in five, three-day gestational age periods between 40 and 42weeks (group 1: 40+0 -40+2 ; group 2: 40+3 -40+5 ; group 3: 40+6 -41+1 ; group 4: 41+2 -41+4 ; group 5: 41+5 -42+0 ). Using Poisson regression, induced deliveries in each of the gestational age periods were compared with all ongoing pregnancies. Propensity score matching was applied to reduce confounding by indication. In the gestational age groups 1 and 2, labor induction significantly decreased the risk of meconium aspiration syndrome [relative risk (RR) 0.40, 95% confidence interval (CI) 0.18-0.91 (group 1), RR 0.44, 95% CI 0.21-0.91 (group 2)] but increased the risk for prolonged hospitalization of a neonate [RR 1.30, 95% CI 1.10-1.54 (group 1) and RR 1.23, 95% CI 1.03-1.47 (group 2)]. In groups 3 and 4, labor induction significantly increased the risk for emergency cesarean section [RR 1.17, 95% CI 1.06-1.28 (group 3) and RR 1.19, 95% CI 1.09-1.29 (group 4)] but still reduced the risk for meconium aspiration syndrome. In group 5, labor induction did not affect the risk for any of the studied outcomes (operative delivery, obstetric trauma, neonatal mortality, respirator treatment, Apgar <7). Propensity score matching is a novel approach to studying the effect of labor induction. It highlighted the conflicting maternal and neonatal risks and benefits of the intervention, and supported expectant management as a valid option, at least until close to 42weeks.

Meconium Stained Amniotic Fluid: Factors affecting Maternal and Perinatal Outcomes at Jimma University Specialized Teaching Hospital, South West Ethiopia

Background: Meconium is not only a potential sign of fetal hypoxia but is also a potential toxin if the fetus aspirates particulate matters with a gasping breath in utero or when it takes its first breaths following birth. In addition to this the condition of the mother who gives birth in such circumstances is a concern. Methods: A hospital based cross-sectional descriptive study was carried out on labouring mothers with meconium stained amniotic fluid who delivered in the labor ward of Jimma University Specialized Hospital during October1, 2012 to December 30, 2012. All labouring mothers with meconium stained amniotic fluid (MSAF) during the study period were included. Data on history of the patient, patient specific demographics and obstetric information was collected using pretested structured questionnaire. Relevant data was abstracted from the neonatal chart and the logbook in the neonatology ward. Statistical tests of association using SPSS (version 16.0, IBM Corporation) were employed at the level of significance of 5%. Results: The overall rate of meconium stained amniotic fluid was 15.4% (151/979) and 74.8% of the cases had moderate to thick meconium stained amniotic fluid. Mode of delivery in 70.2% of cases was operative delivery; and those mothers with a grade three meconium stained liquor had about 5 times increased risk of operative delivery when compared with mothers with grade 1 staining (OR=4.66, 95%CI:1.52-14.30). First minute Apgar score was less than 7 in 88% of the new born while it was less than 4 in 15% of the cases. However, there was no statistically significant association between the thickness of meconium and low first minute Apgar score. Those babies who were delivered with operative delivery had 16 times increased risk of low 5th minute Apgar score. Among the 27.1% of new born sent to the Neonatal Intensive Care Unit, 71.4% (19.9% of the total) were diagnosed to have Meconium Aspiration Syndrome with clinical examination alone. Those new-borns with first minute Apgar score<7 had three times increased risk of MAS (95% CI: 1.087-10.668) and the presence of meconium stained secretion in the oropharynx of a new born resulted in 9 times increased risk of Meconium Aspiration Syndrome. Conclusion: The study revealed that Moderate to thick meconium stained amniotic fluid was associated with increased risk of operative delivery, low 5th minute Apgar score and Meconium Aspiration Syndrome. Shortening the threshold for intervention for labor with fetal heart rate abnormalities in the presence of meconium stained amniotic fluid and introducing further fetal evaluation methods like fetal scalp PH analysis are recommended.

Endotracheal Suction for Nonvigorous Neonates Born through Meconium Stained Amniotic Fluid: A Randomized Controlled Trial

To assess whether endotracheal suctioning of nonvigorous infants born through meconium stained amniotic fluid (MSAF) reduces the risk and complications of meconium aspiration syndrome (MAS). Term, nonvigorous babies born through MSAF were randomized to endotracheal suction and no-suction groups (n=61 in each). Risk of MAS, complications of MAS and endotracheal suction, mortality, duration of neonatal intensive care unit stay, and neurodevelopmental outcome at 9 months were assessed. Maternal age, consistency of meconium, mode of delivery, birth weight, sex, and Apgar scores were similar in the groups. In total, 39 (32%) neonates developed MAS and 18 (14.8%) of them died. There were no significant differences in MAS, its severity and complications, mortality, and neurodevelopmental outcome for the 2 groups. One infant had a complication of endotracheal suctioning, which was mild and transient. The current practice of routine endotracheal suctioning for nonvigorous neonates born through MSAF should be further evaluated. Clinical Trial Registry of India: CTRI/2013/03/003469.

Complications fœtales et néonatales des grossesses prolongées

To evaluate fetal and neonatal outcomes related to prolonged pregnancy. This study is based on Pubmed search, Cochrane library and HAS recommendations. The risk of fetal complications including macrosomia (6 %), oligohydramnios (10 %-15 %), abnormal fetal heart rate pattern and meconium-stained fluid is increased in prolonged pregnancy (≥ 41(+0) weeks). The rate of stillbirth was estimated between 1.6 ‰ and 3.0 ‰ live births according to countries in post-term pregnancies (≥ 42(+0) weeks). The risk of umbilical cord pH less than 7.10, Apgar score at five minutes inferior to 7, ICU admissions and perinatal asphyxia is increased in post-term infants (≥ 42(+0) weeks) compared with term infants. The risk of neurologic complications including neonatal convulsion, hypoxic ischemic encephalopathy, cerebral palsy, developmental deviations and epilepsy in childhood is increased in post-term infants. The risk of meconium aspiration syndrome, neonatal sepsis, and birth trauma including shoulder dystocia and bone fracture is increased in post-term infants. The rate of perinatal mortality increases in post-term infants. The perinatal mortality in post-term infants could be explained by perinatal asphyxia and meconium aspiration syndrome. The risk of perinatal complications and mortality are increased in prolonged pregnancy.

Intrapartum Amnioinfusion in Meconium Stained Amniotic Fluid: An Update

The presence of meconium is associated with an increase in perinatal mortality and morbidity and remains a concern of both obstetriciansand neonatologists. Approximately 8 to 16% of pregnancies may be complicated by the presence of meconium in amniotic fluid. In aboutone third cases, meconium may be present below vocal cords. This poses a risk of meconium aspiration syndrome, which carries amortality rate as high as 25%. Amnioinfusion is a procedure whereby a physiologic solution is infused into the uterine cavity to replace ordilute amniotic fluid. It has been found to relieve umbilical cord compression and dilute meconium, thus reducing the risk of meconiumaspiration. Improved perinatal outcomes have been documented in different studies where intrapartum transcervical amnioinfusion wasadministered to women with meconium stained liquor. It remains a cheap, feasible and good alternative in low resource settings wherefacilities for electronic fetal monitoring are limited.

139: Risk of meconium aspiration syndrome increases with gestational age at term

Meconium is associated with prolonged gestation; thus, it is no surprise that postterm pregnancy is associated with meconium aspiration syndrome (MAS). However, are there other aspects of a prolonged pregnancy which leads to MAS? Given this background, we sought to examine the outcomes by gestational age in women with meconium stained amniotic fluid (MSAF).

A Cochrane Pocketbook: Pregnancy and Childbirth

A Cochrane Pocketbook: Pregnancy and Childbirth

Amnioinfusion for the Prevention of the Meconium Aspiration Syndrome

Meconium-stained amniotic fluid is reported in up to 22% of term deliveries, and varying proportions of infants delivered through meconium-stained fluid develop meconium aspiration syndrome, a condition with reported casefatality rates ranging from 5% to 40%. Randomized trials suggest that amnioinfusion of saline is associated with a reduced risk of meconium aspiration syndrome and operative delivery. This international, randomized, controlled study enrolled 2003 women from 13 countries who had thick meconium staining of amniotic fluid during labor and a singleton fetus with a gestational age of 36 weeks or more. A total of 1998 women were randomly assigned to amnioinfusion or standard care after being stratified according to the presence or absence of variable fetal heart rate decelerations. Amnioinfusion was done by infusing 800 mL of sterile saline transcervically over 40 minutes and continuing until a maximum of 1500 mL was delivered. A total of 1975 women were available for analysis. The study groups were comparable sociodemographically and in baseline obstetric characteristics. More than 90% of women in both groups underwent continuous fetal heart rate monitoring. A composite primary outcome, including perinatal death, moderate or severe meconium aspiration syndrome, or both, occurred in 4.5% of infants in the amnioinfusion group and 3.5% of the control group, for a relative risk (RR) of 1.26 (95% confidence interval [CI], 0.82-1.95). The respective rates of moderate or severe meconium aspiration syndrome were 4.4% and 3.1 %, yielding a RR of 1.39 (95% CI, 0.88-2.19). There were 5 perinatal deaths in each group (0.5%). Mild respiratory distress occurred in approximately 3% of each group. Stratified analysis showed no significant effect of amnioinfusion on the frequency of the primary outcome whether or not fetal heart decelerations were present. Rates of oropharyngeal suctioning, laryngoscopy, and intubation in the delivery room were comparable, as were the proportions of infants having meconium below the vocal cords. Fetal heart rate monitoring demonstrated abnormalities that justified clinical intervention in 14.1% of the amnioinfusion group and 13.9% of the control group (RR, 1.02; 95% CI, 0.79-1.30). No significant group differences were found in rates of cesarean delivery, maternal fever in the peripartum period, maternal death, or serious morbidity. Amnioinfusion for thick meconium staining of amniotic fluid did not lower the risk of perinatal death, moderate or severe meconium aspiration syndrome, or other serious neonatal disorders in this study, and it should not be recommended for this indication when standard peripartum surveillance is assured.

An international randomized controlled trial of amnioinfusion for thickly meconium stained amniotic fluid

To determine if amnioinfusion (AI) for thickly meconium stained amniotic fluid reduces (1) perinatal death and/or moderate to severe meconium aspiration syndrome (primary outcome measure), (2) cesarean section, (3) other indicators of serious neonatal and maternal morbidity. In 56 centres in 13 countries, 1998 laboring women at ≥36 weeks gestation with thickly meconium stained liquor were stratified according to the presence or absence of variable fetal heart rate decelerations and randomized either to standard care or to AI, consisting of a transcervical bolus of 800 mL saline over 40 minutes, followed by infusion of 2 mL/minute to a maximum of 1500 mL. The composite primary outcome measure included perinatal death and/or severe or moderate meconium aspiration syndrome (MAS) based on clinical respiratory distress (severe: requiring mechanical ventilation; moderate: requiring oxygen supplementation at a FiO2 ≥ 40% or of ≥48 hours duration) as blindly adjudicated by a group of 3 neonatologists. Perinatal death and/or moderate or severe MAS occurred in 44 (4.5%) babies in the amnioinfusion group and 34 (3.4%) babies in the control group (RR = 1.3, 95% CI = 0.8-2.0). There was a trend toward more frequent cesarean delivery in the AI group (32% vs 29%; RR = 1.1; 95% CI 1.0-1.3). The distribution of other indicators of severe neonatal morbidity including arterial cord pH < 7.05 and severe maternal morbidity were similar in the two treatment groups. We found no evidence of heterogeneity of treatment effect, either across stratum as defined above, or across centres. For women in labor with thickly meconium stained amniotic fluid, amnioinfusion does not reduce the risk of meconium aspiration syndrome, cesarean delivery, or other major indicators of maternal or neonatal morbidity.

Racial disparity in meconium-stained amniotic fluid and meconium aspiration syndrome in the United States, 1989–2000

Objective To estimate the prevalence of meconium-stained amniotic fluid and meconium aspiration syndrome, as well as the differences in case fatality from meconium aspiration syndrome, between non-Hispanic black and non-Hispanic white infants. Methods We studied non-Hispanic black and non-Hispanic white live births with weights greater than 2.5 kg and gestational ages greater than 35 weeks, using the linked US birth and infant death cohorts for three periods: 1989–1991, 1995–1997, and 1998–2000. We used logistic regression to estimate the risks of meconium-stained amniotic fluid and meconium aspiration syndrome and to estimate the case fatality of meconium aspiration syndrome by maternal race, birth weight, period, and pregnancy complications. Results Risk of meconium-stained amniotic fluid was 80% higher in non-Hispanic blacks when compared with non-Hispanic whites (birth weight–adjusted odds ratio [OR], 1.81, 95% confidence interval [CI] 1.80, 1.82). The prevalence of pregnancy complications did not explain this racial disparity. Risk of meconium aspiration syndrome in non-Hispanic blacks was 67% higher when compared with non-Hispanic whites (birth weight–adjusted OR 1.67, 95% CI 1.64, 1.70). The case fatality rate of meconium aspiration syndrome was similar between non-Hispanic blacks and non-Hispanic whites in the three periods, with rates of 15.5, 15.2, and 11.2 per 1000 in non-Hispanic blacks and 13.5, 11.2, and 10.1 per 1000 in non-Hispanic whites in 1989–1991, 1995–1997, and 1998–2000, respectively. Conclusion Our results suggest that when compared with non-Hispanic whites, non-Hispanic blacks are at significantly greater risk for meconium-stained amniotic fluid and meconium aspiration syndrome but not for meconium aspiration syndrome case fatality.

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.

Racial Differences in the Risk of Meconium Aspiration Syndrome in Relation to Meconium Stained Amniotic Fluid, Fetal Distress and Prolonged Labor

Racial Differences in the Risk of Meconium Aspiration Syndrome in Relation to Meconium Stained Amniotic Fluid, Fetal Distress and Prolonged Labor

Value of Amnioinfusion in Reducing Meconium Aspiration Syndrome

Infusing normal saline into the uterine cavity, or amnioinfusion, is used to reduce the risk of meconium aspiration syndrome in babies born to women in whom the pregnancy is complicated by thick, meconium-stained amniotic fluid. In this retrospective review of 436 such pregnancies amnioinfusion was performed in 110. In 18.2% of infants in the amnioinfusion group meconium was found in the trachea compared with 29.1% of infants in the untreated group. In the treated group respiratory distress occurred in 2.7%, and meconium aspiration syndrome in 1.8%, whereas in the untreated group these frequencies were 10.1 and 5.5%, respectively. We conclude that saline amnioinfusion in pregnancies complicated by thick, meconium-stained amniotic fluid reduces the risk of respiratory distress in the newborn.

Meconium aspiration syndrome: Intrapartum and neonatal attributes

To identify the fetus and newborn at risk for meconium aspiration syndrome the perinatal characteristics of 238 infants delivered through meconium-stained amniotic fluid were prospectively examined. All infants with meconium-stained amniotic fluid were routinely suctioned with a DeLee apparatus before tracheal intubation and suctioning. The type and presence of meconium in the trachea, neonatal breathing before intubation, and Apgar scores were recorded in the delivery room. Intrapartum fetal monitoring data were collected for 80% (190/238) of the mothers and umbilical artery pH for 74% (177/238) of the newborns. Despite suctioning with a DeLee apparatus and endotracheal suctioning, meconium was present in the trachea in 87/238 (37%) and meconium aspiration syndrome developed in 22 (9.2%). A total of 73% of newborns who had meconium aspiration syndrome were delivered through thick meconium. Thick meconium, the presence of fetal tachycardia, and absence of intrapartum fetal cardiac accelerations identified the fetus at high risk for meconium aspiration syndrome. The presence of these monitoring findings and thick meconium should alert obstetricians to the possibility of a fetus that requires intervention. Low umbilical artery pH, Apgar scores less than 5, and meconium in the trachea further characterized the newborn at high risk for meconium aspiration syndrome. The combination of these findings may best identify the infant delivered through meconium-stained amniotic fluid who requires close observation for meconium aspiration syndrome.