Lakota Kruse

Impact of mode of delivery on neonatal complications: Trends between 1997 and 2005

Objective. This study examined whether rates of selected neonatal complications vary by mode of delivery and whether these rates are changing as a result of the increasing cesarean delivery rate. Method. Birth certificates in New Jersey from 1997 to 2005 were matched to hospital discharge records for mothers and newborns. Results. In New Jersey, the total cesarean section rate for 2005 was 35.3%, a relative increase of 46% since 1997 (from 24.2%). Rates of transient tachypnea of the newborn (TTN) and respiratory distress syndrome (RDS), regardless of mode of delivery, increased between 1997 and 2005 from 3.3 to 3.9% and 2.1 to 2.4%, respectively. Newborn injuries declined sharply (from 4.1 to 2.6%), whereas intra-ventricular hemorrhage (IVH) rates remained stable. The rates of RDS, TTN and IVH were highest for cesarean delivery without trial of labor, while the rate of injuries was highest for instrumental vaginal delivery. Conclusion. Neonatal complication rates varied by mode of delivery and decreased with gestational age.

Ambient Air Pollution and the Risk of Stillbirth

The purpose of the present study was to examine the risk of stillbirth associated with ambient air pollution during pregnancy. Using live birth and fetal death data from New Jersey from 1998 to 2004, the authors assigned daily concentrations of air pollution to each birth or fetal death. Generalized estimating equation models were used to estimate the relative odds of stillbirth associated with interquartile range increases in mean air pollutant concentrations in the first, second, and third trimesters and throughout the entire pregnancy. The relative odds of stillbirth were significantly increased with each 10-ppb increase in mean nitrogen dioxide concentration in the first trimester (odds ratio (OR) = 1.16, 95% confidence interval (CI): 1.03, 1.31), each 3-ppb increase in mean sulfur dioxide concentration in the first (OR = 1.13, 95% CI: 1.01, 1.28) and third (OR = 1.26, 95% CI: 1.03, 1.37) trimesters, and each 0.4-ppm increase in mean carbon monoxide concentration in the second (OR = 1.14, 95% CI: 1.01, 1.28) and third (OR = 1.14, 95% CI: 1.06, 1.24) trimesters. Although ambient air pollution during pregnancy appeared to increase the relative odds of stillbirth, further studies are needed to confirm these findings and examine mechanistic explanations.

Delayed diagnosis of critical congenital cardiovascular malformations (CCVM) and pulse oximetry screening of newborns

Objective: Congenital cardiovascular malformations (CCVMs) are relatively common with a prevalence of 5–10 per 1000 live births. Pulse oximetry screening is proposed to identify newborns with critical CCVMs which are missed by routine prenatal ultrasound and by pre‐discharge physical examinations. The purpose of this study was to identify the number of infants with a delayed diagnosis of critical CCVMs potentially detectable by pre‐discharge pulse oximetry screening.

Physician cesarean delivery rates and risk-adjusted perinatal outcomes

OBJECTIVE To compare perinatal outcomes in obstetric practices with high and low cesarean delivery rates. METHODS We conducted a population-based study based on 171,295 singleton births in New Jersey in 1996 and 1997. Vital certificate data for each birth were linked to the corresponding hospital discharge records. Nonsubspecialist obstetricians were divided into three groups based on their cesarean delivery rates during the study period: low (less than 18%), medium (18–27%), and high (greater than 27%). Perinatal mortality, rates of birth injury, and uterine rupture were compared among the physician groups after adjustment for differences in patient risks. RESULTS Physicians in the frequent cesarean delivery group performed more cesarean deliveries for all major indications. Perinatal mortality rates were comparable among the three physician groups. Low and very low birth weight infants delivered by the high-rate physicians did not have a lower risk of mortality. The risk of intracranial hemorrhage was significantly higher for infants delivered by low-rate physicians than for those delivered by medium-rate physicians (adjusted relative risk [RR] 1.53; 95% confidence interval [CI] 1.07, 2.19). Relative to deliveries by medium-rate physicians, deliveries by low-rate physicians were associated with a lower overall risk of uterine rupture (adjusted RR 0.56; 95% CI 0.34, 0.92). Medium-and high-rate groups had similar occurrences of birth injury and uterine rupture. CONCLUSION Low cesarean delivery rates reduced the rate of uterine rupture and were not associated with increased perinatal mortality. The data suggest a small increase in intracranial hemorrhages in infants delivered by physicians who perform relatively few cesarean deliveries.

Disparities in asthma hospitalizations among children seen in the emergency department.

We examined the race/ethnicity variation in the risk of hospitalization among children seen in the emergency department (ED) for asthma. ED and hospitalization records for children 1 to 19 years of age in New Jersey for 2004 and 2005 were linked. The dataset identified 47,548 ED and hospitalizations among 37,216 children. ED and hospitalization rates indicated persistent disparities in pediatric asthma. ED admission rates were similar across race/ethnic groups, suggesting similar management of pediatric asthma patients once they are seen in the ED. Integrating existing ED and hospitalization records will enhance asthma surveillance and the targeting of interventions to reduce race/ethnicity disparities.

Longitudinal Patterns of Breastfeeding Initiation

Breastfeeding, in spite of proven benefits and energetic promotion, lags behind national goals, is less prevalent in disadvantaged populations, and declines across successive children in a family. Using longitudinally linked data from the New Jersey Electronic Birth Certificate (EBC) from 1996 to 2001, we found considerable fluidity in breastfeeding status at hospital discharge for births to the same mother. Among mothers who breastfed exclusively after the first birth, only 69% did so after the second (we refer to this as recurrence). Among mothers who exclusively formula fed after the first birth, 16% initiated exclusive breastfeeding after the second birth (referred to as recruitment). Combination feeding the first born, i.e., breastfeeding supplemented by formula, was followed by exclusive breastfeeding for 38% of second births. Rates of recurrence and recruitment differed in distinct ways by race/ethnicity and immigrant status. We conclude that breastfeeding initiation is not necessarily or exclusively a matter of fixed preferences, and that opportunities exist to expand breastfeeding to realize national goals by enhancing both recurrence and recruitment.

Does ambient air pollution trigger stillbirth

Objective: We previously reported an increased risk of stillbirth associated with increases in trimester-specific ambient air pollutant concentrations. Here, we consider whether sudden increase in the mean ambient air pollutant concentration immediately before delivery triggers stillbirth. Methods: We used New Jersey linked fetal death and hospital discharge data and hourly ambient air pollution measurements from particulate matter ⩽2.5 mm (PM2.5), carbon monoxide (CO), nitrogen dioxide (NO2), and sulfur dioxide (SO2) monitors across New Jersey for the years 1998–2004. For each stillbirth, we assigned the concentration of air pollutants from the closest monitoring site within 10 km of the maternal residence. Using a time-stratified case-crossover design and conditional logistic regression, we estimated the relative odds of stillbirth associated with interquartile range (IQR) increases in the mean pollutant concentrations on lag day 2 and lag days 2 through 6 before delivery, and whether these associations were modified by maternal risk factors. Results: The relative odds of stillbirth increased with IQR increases in the mean concentrations of CO (odds ratio [OR] = 1.20, 95% confidence interval [CI] = 1.05–1.37), SO2 (OR = 1.11, 95% CI = 1.02–1.22), NO2 (OR = 1.11, 95% CI = 0.97–1.26), and PM2.5 (OR = 1.07, 95% CI = 0.93–1.22) 2 days before delivery. We found similar associations with increases in pollutants 2 through 6 days before delivery. These associations were not modified by maternal risk factors. Conclusion: Short-term increases in ambient air pollutant concentrations immediately before delivery may trigger stillbirth.

Prenatal Care and Subsequent Birth Intervals

CONTEXT Prenatal care generally includes contraceptive and health education that may help women to control their subsequent fertility. However, research has not examined whether receipt of prenatal care is associated with subsequent birthspacing. METHODS Longitudinally linked birth records from 113,662 New Jersey women who had had a first birth in 1996-2000 were used to examine associations between the timing and adequacy of prenatal care prior to a womans first birth and the timing of her second birth. Multinomial logistic regression analyses adjusted for social and demographic characteristics, hospital and year of birth. RESULTS Most women (85%) had initiated prenatal care during the first trimester. Women who had not obtained prenatal care until the second or third trimester, or at all, were more likely than those who had had first-trimester care to have a second child within 18 months, rather than in 18-59 months (odds ratios, 1.2-1.6). Similarly, women whose care had been inadequate were more likely than those who had had adequate care to have a short subsequent birth interval (1.2). The associations were robust to alternative measures of prenatal care and birth intervals, and were strongest for mothers with less than 16 years of education. CONCLUSIONS Providers should capitalize on their limited encounters with mothers who initiate prenatal care late or use it sporadically to ensure that these women receive information about family planning.

Amniotic fluid embolism-risk factors, maternal and neonatal outcomes

Objective. To investigate demographic characteristics, risk factors, maternal and neonatal outcomes of all cases of amniotic fluid embolism that occurred in New Jersey during 1997–2005. Methods. Information was derived from a perinatal linked dataset provided by the MCH-Epidemiology Program in the New Jersey Department of Health. Bivariate analysis for dichotomous variables used the Chi-square test. Stepwise logistic regression models were created to assess the influence of potential risk factors and p value < 0.05 considered statistically significant. Results. Forty-five cases of amniotic fluid embolism were identified among 1,004,116 deliveries, for a prevalence rate of 1 in 22,313 pregnancies. Statistically, significant association was found with multifetal pregnancy, caesarean section, placenta previa, placental abruption, eclampsia and cervical laceration. The rate of maternal complications such as coagulopathy, seizures, neurological damage, shock and cardiac arrest were significantly greater in the cases as compared with the overall study population. Neonatal morbidity was significant as demonstrated by higher NICU admissions and neonatal intubation rates and lower 5-min Apgar scores. Conclusions. Significant correlation was identified between historically reported risk factors and amniotic fluid embolism. The fetal and maternal mortality rates were lower compared with previous studies, attributed both to improvements in perinatal healthcare and reporting of ‘milder’ cases.

Risk of peripartum hysterectomy by mode of delivery and prior obstetric history: data from a population-based study

PurposeTo provide an estimate of the incidence of peripartum hysterectomy in the state of New Jersey and calculate the effect of mode of delivery and prior obstetric history.MethodsA perinatal-linked dataset provided by the Maternal Child Health Epidemiology Program in the New Jersey Department of Health was used to obtain information from birth certificates and hospital discharge records. Using multivariate logistic regression, various demographic and clinical factors were assessed for association with peripartum hysterectomy.ResultsA total of 1,004,116 births were identified between 1997 and 2005 and 853 peripartum hysterectomies were performed (0.85/1,000 deliveries). Parity increased the risk of hysterectomy with nulliparous women having approximately half the risk compared to multiparous women. Cesarean delivery with no previous c-section almost doubled the risk (OR 2.20, CI 1.80–26.69) while in the presence of a previous c-section the risk was almost four times higher (OR 4.51, CI 3.76–5.40). Operative vaginal delivery did not result in any increase in the risk.ConclusionsMode of delivery and prior obstetric history are major risk factors for peripartum hysterectomy. Patients desiring cesarean delivery need to be counseled on the risk of this serious complication.