Variations in mortality and morbidity by gestational age among infants born at term.

OBJECTIVE: To examine the risks of infant death and neonatal morbidity by week of gestation at term. STUDY DESIGN: National U.S. birth cohort study on the basis of singleton live births in 1995-2001 at 37 to 41 completed weeks gestational age (GA), with exclusion of congenital anomalies. Main outcomes included neonatal, postneonatal, and cause-specific infant death; low-Apgar score at 5 minutes; receipt of neonatal mechanical ventilation >or=30 minutes; neonatal seizures; birth injury; and meconium aspiration syndrome. To reduce confounding by indication, we carried out a secondary analysis restricted to low-risk deliveries. RESULTS: In non-Hispanic white women, the mortality rate decreased with increasing GA from 37 to 39 weeks, remained stable from 39 to 40 weeks, and then (for neonatal death) increased at 41 weeks. Rates of low 5-minute Apgar score and mechanical ventilation showed a U-shaped relation across term GAs, and rates of meconium aspiration syndrome and birth injury rose with increasing GA. Results were similar among infants born to low-risk mothers and in non-Hispanic black women. CONCLUSIONS: Term infants show considerable heterogeneity across gestational age in neonatal and late infant outcomes, even when born to mothers at low risk. Recent trends toward earlier labor induction may have adverse health impacts.

The Pediatric Respiratory Assessment Measure: a valid clinical score for assessing acute asthma severity from toddlers to teenagers.

OBJECTIVE: To determine the performance characteristics of the Preschool Respiratory Assessment Measure (PRAM) in preschool and school-aged children with acute asthma. STUDY DESIGN: In a prospective cohort study, we examined the validity, responsiveness, and reliability of the PRAM in children aged 2 to 17 years with acute asthma. The study involved more than 100 nurses and physicians who recorded the PRAM on triage, after initial bronchodilation, and at disposition. Predictive validity and responsiveness were examined using disposition as outcome. RESULTS: The PRAM was recorded in 81% (n = 782) of patients at triage. The PRAM at triage and after initial bronchodilation showed a strong association with admission (r = 0.4 and 0.5, respectively; P < .0001), thus supporting its ability to distinguish across severity levels. The responsiveness coefficient of 0.7 indicated good ability to identify change after bronchodilation. The PRAM showed good internal consistency (Cronbach alpha = 0.71) and inter-rater reliability (r = 0.78) for all patients and across all age groups. CONCLUSIONS: Good performance characteristics were observed in all age groups, making the PRAM an attractive score for assessing asthma severity and response to treatment.

Are babies born to short, primiparous, or thin mothers "normally" or "abnormally" small?

OBJECTIVES: To examine whether the smaller size of infants born to primiparous, short, or thin mothers is associated with increased risks of perinatal mortality. STUDY DESIGN: We compared gestational age-specific patterns of "revealed" small-for-gestational-age (SGA) birth (number of SGA births expressed as a proportion of fetuses remaining in utero at each gestational age) with the patterns for perinatal mortality among singleton late fetal deaths and live births (n = 791,523) to Swedish mothers in 1992 to 2001. RESULTS: Based on a single standard for SGA, primiparae were at substantially higher risk of revealed SGA throughout gestation, paralleling the pattern for perinatal mortality. However, for short and thin women, risks of revealed SGA were much more consistent with those for perinatal mortality when SGA was based on height-specific or body mass index-specific standards, respectively, rather than on the single standard. Overweight and obese mothers had lower revealed SGA rates based on either standard but higher perinatal mortality rates. CONCLUSIONS: Slower fetal growth due to maternal short stature or low prepregnancy body mass index appears to be physiologic, whereas the slower growth of fetuses born to primiparous women is associated with higher risks of perinatal death.