Psychosocial factors and small-for-gestational-age infants among parous Scandinavian women

BACKGROUND

We wanted to analyze the association between small-for-gestational-age (SGA) births, defined as a newborn with a birthweight below the 15th percentile-for-gestational age, and socioeconomic and psychosocial risk factors.

METHODS

Information on social background, psychological status, and life events was collected prospectively by use of questionnaires in the second and third trimester of pregnancy. The respondents were 1552 women who expected their second or third child and took part in a Scandinavian multicenter study of fetal growth and perinatal outcome.

RESULTS

No significant differences were found in relational stress, state and trait anxiety, depression, and physical strain between SGA and non-SGA births, whereas smoking around time of conception and low prepregnant body mass were significant SGA birth predictors. Maternal and paternal education of nine years or less increased the SGA birth risk (RR 1.46 (95% CL 1.12; 1.92) and RR 1.34 (95% CL 1.01; 1.79), respectively. The increased risk from a low maternal education was still significant when body mass and low paternal education were controlled, but not after adjustment for maternal smoking. A protective effect of paternal, but not maternal, education of 12 years or more was also observed and retained its effect when maternal smoking and body mass were controlled.

CONCLUSION

In this seemingly homogeneous Scandinavian population, parental education and maternal body proportion and life style influenced the prevalence of small-for-gestational-age births. Relational stress, anxiety, depression, and physical strain did not influence birth outcome.

Prediction of fetal growth based on maternal serum concentrations of human chorionic gonadotropin, human placental lactogen and estriol

BACKGROUND

The purpose was to determine the usefulness of maternal serum concentrations of human chorionic gonadotropin (hCG), human placental lactogen (hPL) and estriol as predictors of fetal growth.

METHOD

From a large cohort serum obtained serially at 17, 25, 33 and 37 weeks of gestation were analyzed for randomly selected pregnancies resulting in small for gestational age (SGA, n = 102) and non-SGA (n = 112) infants.

RESULTS

There were no significant correlations between birthweight ratio (ratio of birthweight to mean weight for gestational age) and hCG, but between birthweight ratio on one hand and estriol for all stages of pregnancy (r = 0.19-0.38, p < 0.01 - p < 0.001) and hCL except at 33 weeks (r = 0.11-0.40, p ns-p < 0.001) on the other. There were statistically significant, but small median differences and substantial overlaps between the SGA and non-SGA infants for hCG at 17 and 37 weeks, for hPL at 17, 33 and 37 weeks, and for estriol at all the stages of pregnancy. The sensitivity and positive predictive value of low hormone concentrations (below the 10th percentile) in predicting the birth of an SGA infant were in the range of 6-26% and 17-39%, respectively. The corresponding specificity and prediction of a non-SGA infant from normal levels were 91-93% and 85-88%.

CONCLUSIONS

HPL and estriol, but not hCG concentrations, are positively related to the size of the fetus, but the relationships are too weak to be of predictive value in an unselected population.

Coexistence of hemimegalencephaly and chronic encephalitis. Detection of cytomegalovirus by the polymerase chain reaction

We report the extraordinary association of hemimegalencephaly with chronic encephalitis and cytomegalovirus (CMV) positivity in a 5-month-old infant with intractable seizures and a left hemisphere resection. Microscopy revealed a severe neuronal migration disorder (NMD) with fusion of gyri, marked disarray of neuronal lamination, neuronal gigantism and extensive neuronal heterotopias. Also widespread were microglial nodules, gliosis and nodular calcifications and some foci of frank necrosis with calcification. Occasional perivascular and leptomentingeal lymphocytic infiltrates were present. No viral inclusions were identifiable. Polymerase chain reaction on multiple specimens showed unequivocal CMV positivity. In intrauterine CMV infection. NMDs such as polymicrogyria are well recognized, but the association of hemimegalencephaly with CMV infection has not previously been described. Our finding of chronic encephalitis with CMV positivity and hemimegalencephaly in the same patient raises questions about the role of CMV in the etiopathogenesis of the NMD.

Cell division in placentas of appropriate and small-for-gestational-age infants. A flow cytometry study

BACKGROUND

The purpose of this study was to examine if placentas of small- for-gestational-age (SGA) and non-SGA infants differ with respect to proliferative cell activity.

METHOD

Cell cycle distribution was studied in placentas from 181 SGA (birthweight < 10th percentile) and 528 non-SGA births by flow cytometry measurements of relative DNA content.

RESULTS

The fraction of cells in various cell cycle phases (G1-, S- and G2-phases) did not differ with gestational age from 30 to 43 weeks in either of the groups. The placentas of the SGA infants had a significantly lower mean (+/-1 SEM) growth fraction than placentas of non-SGA infants (S-phase 5.2 +/- 0.2 vs 5.5 +/- 0.1, p = 0.05, and G2-fraction 5.4 +/- 0.2 vs 6.3 +/- 0.1, p < 0.001), but the overlaps of the distributions were large. Thus sensitivity, specificity and predictive values of low fractions did not differ substantially-from a purely random prediction of SGA.

CONCLUSIONS

Cell division in the placenta is maintained until and beyond term. Placentas of SGA infants have on average, lower proliferative activity than placentas of non-SGA infants, but the difference is too small to be of predictive value in identifying intrauterine growth retardation.

Intrauterine growth pattern by the tendency to repeat small-for-gestational-age births in successive pregnancies

BACKGROUND

Fetuses of women who repeat small-for-gestational-age births in successive pregnancies may have a different intrauterine growth pattern than SGA birth of non-repeater mothers. Also repeated SGA births may grow differently depending on whether the tendency to repeat is due to some external factors such as cigarette smoking ("false repeaters") or due to genetic or intrinsic factors ("true repeaters").

MATERIAL AND METHODS

Fetal growth were compared in a "nested case-control" study within a longitudinal (cohort) study, comparing three types of SGA births, 23 of "true repeater" mothers, 46 of "false repeater" mothers and 65 of non-repeater mothers, and these were compared with 1017 non-SGA births. Fetal growth was compared using a regression analysis based on repeated measurements (four for each woman).

RESULTS

For mean abdominal diameter the "true repeater" SGA births grew more slowly towards the end of pregnancy. However, the growth curves show only minor differences between the three types of SGA births, but the patterns are grossly different from the growth of non-SGA births (controls).

CONCLUSION

The intrauterine growth retardation starts early in pregnancy, and is not strikingly different between births of repeater and non-repeater mothers.

The relationship between maternal characteristics and fetal and neonatal anthropometric measurements in women delivering at term: a summary

BACKGROUND

We wanted to determine the relationship between a number of maternal characteristics and various fetal and neonatal anthropometric measurements determined by ultrasound and at birth.

METHODS

A total of 1205 term singleton maternal-infant pairs were studied. Various ultrasound measurements obtained at 18, 24, 30 and 36 weeks' gestation and neonatal anthropometric measurements obtained at birth were studied in relationship to various maternal characteristics using univariate and multivariate techniques.

RESULTS

Black race, female sex, cigarette smoking, drug use, having a previous low birthweight infant, maternal hypertension and being short or thin or failing to gain weight each resulted in a birthweight decrease of 100 to 300 g. The effect of each of these characteristics on each ultrasound measurement, the timing of the effect, and its ultimate effect on neonatal anthropometric measurements are described.

CONCLUSION

The data presented in this paper provide a more complete understanding of the relationship between maternal characteristics, infant sex, and various fetal ultrasound and neonatal measurements.

Growth and development during the first year in a cohort of low income term-born American children

BACKGROUND

Infants born small for gestational age (SGA) are at risk for poor postnatal growth and development. This study evaluates biologic and environmental determinants of outcome during the first year of life in a cohort of low income term-born American infants.

METHODS

Seven hundred and seventeen of 949 (76%) singleton births to women followed from early pregnancy were studied over their first year of life and measures of growth, home environment, physical and cognitive development were obtained. Infants were categorized as SGA or non-SGA based on birthweight < 15th percentile for gestational age. SGA and non-SGA children's outcomes were analyzed by race, gender and symmetry.

RESULTS

SGA infants were demographically similar to non-SGA infants but significantly lower in mean maternal height, weight and education. Birthweight, crownheel length and head circumference were all significantly smaller in SGA infants. By age 1 year, the SGA children were still shorter, lighter and had smaller head circumferences than the non-SGA children though their rate of growth during the first year was significantly greater for length and head circumference. Cognitive functioning as measured by the Bayley Scales of Infant Development and the Fagan Test of Infant Intelligence did not differ significantly except for a lower Bayley Psychomotor Development Index (PDI) in SGA infants. Since most of these children live in economically disadvantaged households, any negative consequences of poor intrauterine growth may be influenced by postnatal environment and longer term follow-up will be necessary to assess this relationship.

The relationship between maternal dietary intake and infant birthweight

BACKGROUND

Zinc and folate are important for fetal growth. However, the relationship between the dietary intake of these nutrients and pregnancy outcome is not settled.

METHODS

A prospective study was conducted to ascertain the relationship between maternal dietary zinc and folate intake (n = 1398), serum zinc and folate levels (n = 289), and infant birthweight. Twenty-four hour recalls were used to measure energy, zinc, folate and other nutrient intakes at 18 and 30 weeks of gestation. Subjects in the study were offered daily folic acid (1.0 mg) and iron (60 mg as ferrous sulfate) at enrollment.

RESULTS

Maternal zinc nutriture as assessed by serum and dietary intake was not associated with birthweight or length of gestation. There was a small but significant positive association between maternal folate intake and adjusted infant birthweight (beta = 0.05, p = 0.03). The indirect measures of maternal nutritional status including maternal pre-pregnancy weight (beta = 8.0, p = 0.0001) and weight gain during pregnancy (beta = 18.1, p = 0.0001) were stronger predictors of adjusted infant birthweight as compared to energy intake and intake of zinc and folate. An increase of 320, 290, and 48 g in infant birthweight was associated with the 90th-10th percentile difference for pre-pregnancy weight, weight gain during pregnancy, and folate intake respectively.

CONCLUSION

These results indicate that pre-pregnancy weight and weight gain during pregnancy are both strong predictors of infant birthweight. Folate intake, although significantly associated with birthweight, was a weak predictor while maternal intake of zinc and other nutrients was not associated with birthweight.

Small-for-gestational-age (SGA) infants born at term: growth and development during the first year of life

BACKGROUND

The purpose was to compare growth patterns and psychomotor development of healthy small-for-gestational-age (SGA) and non-SGA infants, and identify factors predictive of outcome at 13 months of age.

METHOD

A total of 265 SGA infants and 329 non-SGA controls were identified from a multicenter cohort of 5722 para 1 and 2 women who had been followed during pregnancy. The infants were examined at 2 days and at 13 months of age. Psychomotor development at 13 months was assessed with The Bayley Scale of Infant Development.

RESULTS

The SGA infants showed partial catch-up growth, but had still lower (mean +/- SEM, p < 0.0001) weight (9750 +/- 65 vs 10505 +/- 67 g), crown-heel length (75.9 +/- 0.2 vs 77.5 +/- 0.2 cm) and head circumference (46.9 +/- 0.1 vs 47.7 +/- 0.1 cm) than the non-SGA infants at 13 months. The SGA children scored equally well on the motor (PDI 106.8 +/- 1.0 vs 107.2 +/- 0.8) but lower on the mental scale (MDI 112.1 +/- 0.8 vs 116.5 +/- 0.7, p < 0.0001) of the Bayley Scale, and the asymmetric SGA scored lower than the symmetric SGA infants (MDI 110.2 +/- 1.3 vs 113.3 +/- 0.9, p = 0.05). In a multivariate regression analysis the parents' growth parameters had the greatest effect on growth measures at 13 months while education and maternal smoking had no significant effect. SGA vs non-SGA status had the greatest effect on growth velocities during infancy. For mental development only SGA vs non-SGA status and the mothers' education made significant contributions, but only accounted for 6% of the variance.

CONCLUSION

The negative impact of intrauterine factors on growth are partly abolished by catch-up growth during infancy, and growth parameters at one year of age are mostly determined by genetic factors even in SGA infants. Decreased intrauterine growth may possibly have a negative effect on brain growth and mental developmental potential.

Choices in the 1990s for the management of pediatric cerebral arteriovenous malformations

A retrospective 45-year analysis of the management of 160 children with intracranial arteriovenous malformations at The Hospital for Sick Children, Toronto, reveals substantially improving outcomes which relate to more efficient diagnoses and treatments. 80% of children will declare their malformation by means of spontaneous intracranial hemorrhage. For those children who present with hemorrhage or epilepsy, 80% will require an operation. The overall mortality rate has declined to 12% since 1975 and that for the cerebellar lesions from 67 to 42%. 53% of the patients operated upon will be neurologically normal. Endovascular embolization of a child's AVM is a customized, partial solution for a limited number of children. Stereotactic radiosurgery will be used increasingly to obliterate those small lesions in children which are unassociated with hemorrhage or are the residua of an operation. As many as 10% of children (15/160) with diagnosed AVMs cannot be helped with operative or other interventional therapies. The recognition of the pediatric stroke syndromes, the early triage and diagnosis of a child's cerebral hemorrhage, the operative and anaesthetic technologies and the adjunct therapies - choices of the nineties - have resulted in a 66% decline in the overall mortality from this vascular lesion as well as greater assuredness that for most the lesion can be permanently obliterated.

Home apnea monitoring and sudden infant death syndrome

OBJECTIVE

To estimate the U.S. national prevalence of apnea monitor use by birth weight classification and to examine the relationship between the use of apnea monitors and the occurrence of Sudden Infant Death Syndrome (SIDS).

DESIGN AND SETTING

Data obtained from the 1988 National Maternal and Infant Health Survey (NMIHS) were used. Prevalence estimates of apnea monitor use were obtained by weighting survey data, and the relationship between monitor use and SIDS was accomplished by a case-control analysis using SIDS deaths and live controls obtained from the NMIHS.

OUTCOME MEASURE

Weighted estimates of the prevalence of apnea monitor use and odds ratios for the odds of use of an apnea monitor among SIDS victims compared with the odds of use of an apnea monitor among living controls.

RESULTS

The national prevalence estimates for home apnea monitor use among birth weight strata of 500 to 1,499 g, 1,500 to 2,499 g, and 2,500 g or more for blacks were 19.9, 2.6, and 1.1% compared with 44.0, 8.8, and 1.2% for non-blacks. The only significant association between the use of apnea monitors and SIDS was for black 500- to 1,499-g infants. The adjusted odds ratio for SIDS among monitored black 500- to 1,499-g infants vs unmonitored infants was 3.93 (1.09, 14.17).

CONCLUSIONS

This analysis suggests a marked difference in reported monitor use between U.S. black and non-black infants. In addition, black very low birth weight infants at highest risk for SIDS appear to be preferentially selected for monitoring. The protective effect of home apnea monitoring in this survey population is unclear.

Medical, psychosocial, and behavioral risk factors do not explain the increased risk for low birth weight among black women

OBJECTIVE

Our purpose was to determine whether various demographic, behavioral, housing, psychosocial, or medical characteristics explain the difference in pregnancy outcome between black and white women.

STUDY DESIGN

A sample of 1491 multiparous women with singleton pregnancies, 69% of whom were black and 31% of whom were white and who enrolled for care between Oct. 1, 1985, and March 30, 1988, participated in the study. The frequencies of various demographic, medical environmental, and psychosocial risk factors among black and white women were determined. The outcome measures were birth weight, gestational age, fetal growth restriction, preterm delivery and low birth weight.

RESULTS

White infants were heavier and born later than black infants. The white women in this sample smoked more cigarettes, moved more frequently, and had worse psychosocial scores. The black women had lower incomes, were less likely to be married, and had more hypertension, anemia, and diabetes. Besides race, only maternal height, weight, blood pressure, diabetes, and smoking had a consistent impact on outcome and did not explain the difference in outcome between the two groups.

CONCLUSION

In this low-income population, many of the risk factors for low birth weight were more common among white women than black women. Nevertheless, black women had more infants born preterm, with growth restriction, and with low birth weight than did white women. The various maternal characteristics studied did not explain these differences.

Procedure of lateral canthal advancement for the treatment of coronal synostosis

The procedure of lateral canthal advancement has been used at the Hospital for Sick Children, Toronto, since 1973. The patients treated by this technique between 1973 and 1993 consisted of 41 with unilateral coronal synostosis, 13 with trigonocephaly and 29 with craniofacial dysostosis. The results have been excellent in patients with unilateral coronal synostosis and trigonocephaly. Furthermore, 17 of the infants with craniofacial dysostosis needed no further treatment after their initial operation.

Prenatal weight gain patterns and birth weight among nonobese black and white women

OBJECTIVE

To examine the association between prenatal weight gain patterns and birth weight, using Institute of Medicine (IOM) guidelines.

METHODS

Data from a prospective follow-up study of risk factors for fetal growth restriction were used to examine the impact of low weight gain on mean birth weight. A total of 415 nonobese (body mass index [BMI] less than 26) black (n = 275) and white (n = 140) women who delivered at term were included in this analysis. Linear regression analysis was used to examine the impact of low first-trimester gain (less than 2.3 kg with low BMI [less than 19.8]; less than 1.6 kg with normal BMI [19.8-26.0]) and low second- and third-trimester rates of gain (less than 0.38 kg/week with low BMI; less than 0.37 kg/week with normal BMI) on mean birth weight while controlling for selected sociodemographic and reproductive variables.

RESULTS

Patterns with low gain in the first and second or in the second and third trimesters were associated with significant decreases in mean birth weight, ranging from 206 to 265 g; low gain in only the first or third trimester was not associated with a significant decrease in mean in birth weight. The impact of low gain on mean birth weight varied by ethnic group.

CONCLUSION

These observations suggest that inadequate patterns of prenatal weight gain, defined by IOM guidelines, are associated with decreased birth weight, particularly when the patterns involve low second-trimester gain.

Supratentorial primitive neuroectodermal tumors in children

A retrospective review of 36 children diagnosed with a supratentorial primitive neuroectodermal tumor (PNET) at the Hospital for Sick Children was performed for the period 1970-1995. All children but one received their initial treatment at our institution. There were 18 males and 18 females and the median age at diagnosis was 35 months. Twenty-two PNETs were lobar, 3 were deep in the hemisphere, and 10 were located in the pineal region. One child presented with intracranial leptomeningeal disseminated disease. The tumors were mostly undifferentiated although 22 had some evidence of differentiation along one or more neuroepithelial lines. Five children had a biopsy, 24 had subtotal resection, and 7 had gross total resection. Twenty-six children had adjuvant radiotherapy and 13 had chemotherapy. At last follow-up 30 patients were dead and 6 were alive. The median survival was 23 months and the 2, 3, and 5 year survivals were 50%, 34%, and 18% respectively. All of the survivors received craniospinal radiation and 4 received chemotherapy. There was a statistically significantly worse survival in young children. There was a trend to better survival in children treated since 1984, and in children undergoing gross total resection. Because of the extremely poor survival, we recommended that all children undergo gross total resection followed by chemotherapy. For children older than 3 years of age craniospinal radiation should also be given.

Current treatment of thalamic gliomas in children

Historically, the outcome of children with thalamic gliomas has been poor. Because of the potential for severe perioperative mortality, conservative approaches toward these lesions have been commonly instituted. However, recent improvements in therapeutic approaches have been numerous. These refinements have most importantly centered on improving the neurosurgical technique of tumor resection by integrating computer-assisted, stereotactic approaches. In so doing, perioperative mortality has dropped from as high as 40% to as low as 0-1%. Gross total resection confirmed with postoperative imaging is becoming an expectation. However, because of anatomical limitations or malignant histology, incomplete resections will undoubtedly occur in an effort to preserve neurological function. At the same time, not all residual disease implies a poor outcome. Indolent, low-grade gliomas of childhood are not limited to the cerebellum or optic/hypothalamic regions, and histologically similar lesions in the region of the thalamus occur with some frequency. In this case scenario, incompletely resected low-grade lesions should be followed sequentially with routine imaging; further therapy, be it surgical or adjuvant, is instituted only if disease progression is documented. Children found to have malignant gliomas of the thalamus should undergo surgical resection in an effort to relieve them of any existing mass effect. Subsequently, adjuvant therapy is utilized depending on the exact histopathology and the child's age. Thus, what evolves from recent data and current surgical techniques is an aggressively directed therapy based upon anatomical considerations and tumor type.

Infantile spasms: cerebral blood flow abnormalities correlate with EEG, neuroimaging, and pathologic findings

This ongoing study examines abnormalities of cerebral perfusion in a consecutive series of children with infantile spasms and correlates cerebral blood flow (CBF) abnormalities with electroencephalographic (EEG), neuroimaging, and pathologic findings. A consecutive series of children with infantile spasms, diagnosed by standard clinical and EEG criteria, had cerebral perfusion studies using 99Tc-HmPAO single photon emission computed tomography (SPECT), together with neuroimaging studies using computed tomography (CT) and/or magnetic resonance imaging (MRI), interpreted independently and correlated with surgical pathologic findings. Twenty children aged 2-13 months (mean 9.3 months) were studied over a 4-year period; 60% had symptomatic infantile spasms due to cerebral dysgenesis (33%), other congenital lesions (25%), tuberous sclerosis (17%), or other causes (25%), and the remaining patients were cryptogenic (40%). CBF abnormalities were present in 85%: multifocal decrease (40%), focal increase (25%), diffuse decrease (15%), and focal increase (10%), while the remaining 15% had normal cerebral blood flow. Focal cortical lesions may lead to infantile spasms, even in cryptogenic patients diagnosed by functional neuroimaging such as 99Tc-HmPAO SPECT. In selected patients, surgical excision of the cortical lesions leads to improved seizure control and possibly outcome. The localization and surgical excision of focal cortical lesions in infantile spasms required further investigation with functional and structural neuroimaging, EEG, and intraoperative electrocorticography.

Exercise, employment, other daily activities, and adverse pregnancy outcomes

The relations of exercise, employment, and other daily activities during pregnancy with pregnancy outcomes were examined using data from the Missouri Maternal and Infant Health Survey. Maternal surveys were available for the following singleton birth categories: 450 fetal deaths; 782 very low birth weight (VLBW, < 1,500 g); 802 moderately low birth weight (MLBW, 1,500-2,499 g); and 794 normal birth weight (NBW, > or = 2,500 g). All mothers were Missouri residents at the time of their December 1989 to March 1991 deliveries. It was found that VLBW mothers had exercised during pregnancy significantly less than NBW mothers. When compared with NBW mothers before pregnancy, VLBW mothers had been just as likely not to exercise as NBW mothers (odds ratio (OR) = 0.88, 95% confidence interval (CI) 0.69-1.12). During the first, second, and third trimesters, the odds ratios decreased to 0.70 (95% CI 0.53-0.92), 0.54 (95% CI 0.40-0.74), and 0.33 (95% CI 0.20-0.53), respectively. The VLBW mothers also were less likely to exercise during the third trimester than MLBW mothers (OR = 0.34, 95% CI 0.21-0.54) or mothers with fetal deaths (OR = 0.36, 95% CI 0.19-0.67). During the 3 months after pregnancy, none of the exercise odds ratios were statistically significant between groups. No significantly increased risks were found between employment during pregnancy or other daily activities and adverse pregnancy outcome. The study supports the recently relaxed guidelines of exercise during pregnancy.

What's new in pediatric neurosurgery

During the past year, there have been some significant papers dealing with pediatric neurosurgical problems. These papers deal with arteriovenous malformations, spinal cord injury, brain tumors and hydrocephalus. The papers are summarized in the following review.

Location of epileptic foci on interictal and immediate postictal single photon emission tomography in children with localization-related epilepsy

Several neuroimaging techniques that supplement electrophysiologic methods of evaluating pediatric patients with localization-related epilepsies before surgery assess both structural and functional abnormalities. For example, single photon emission computed tomography (SPECT) with technetium-99m-hexamethylpropyleneamine oxime (99mTc-HMPAO) has been used to demonstrate abnormal cerebral perfusion. States of cerebral perfusion during the interictal and immediate postictal periods have been reported to correlate with epileptiform foci identified by electroencephalogram (EEG). Between January 1987 and March 1993, we studied 55 pediatric patients with intractable seizures with prolonged video EEG telemetry in the epilepsy monitoring unit, followed by computed tomography, magnetic resonance imaging, and SPECT, before surgery to determine whether SPECT studies with 99mTc-HMPAO improved the accuracy of locating the epileptic focus. Interictal SPECT was performed on all patients, and immediate postictal SPECT (within 10 minutes after seizure ended) on 17 patients monitored in the epilepsy monitoring unit. In 15 (88%) of the 17, the combination of interictal and postictal SPECT studies yielded results corresponding to the EEG abnormality, a result significantly better than that obtained from interictal studies alone: 21 (55%) of 38 (chi 2 = 5.647, P = .0175). SPECT scans showed localized abnormal perfusion in the ipsilateral temporal lobe in all six patients with mesial temporal sclerosis, but precise results were not obtained in cases of dual pathology and neuronal migration disorders. Depiction of cerebral perfusion by interictal and immediate postictal SPECT studies can lead to greater accuracy in the localization of epileptic foci.

Prematurity, sudden infant death syndrome, and age of death

OBJECTIVE

To determine if preterm infants are at greater risk for sudden infant death syndrome (SIDS) than term infants and to determine if the postconceptional age of SIDS deaths varies by gestational age at birth.

METHODS

A cohort analysis was conducted using data from the 1987 United States' Birth Cohort Linked Birth/Infant Death Certificate tapes. SIDS was defined as the death of any infant who was > 24 weeks gestation at birth; weighed > 500 g at birth; was assigned an International Classification of Diseases-9th Revision (ICD-9) underlying cause of death of 7980; and had an autopsy.

RESULTS

The overall SIDS rate using our definition was 1.20 deaths/1000 live births. The SIDS rates by gestational age categories of 24 to 28 weeks, 29 to 32 weeks, 33 to 36 weeks, and 37 or more weeks were 3.52, 3.01, 2.27, and 1.06 deaths/1000 live births, respectively. Because of misclassification of gestational age among the most preterm infants, a restricted analysis was conducted on SIDS victims whose gestational ages fell within cutoff values derived from a methodology that excluded gestational age assessments assumed to be invalid. This subgroup analysis showed a mean (standard deviates) postconceptional age of death for SIDS for infants of 24 to 28 weeks, 29 to 32 weeks, and 33 to 36 weeks gestation to be 45.8 (8.3), 47.3 (8.6), and 48.0 (8.3) weeks, respectively, compared with 52.3 (8.5) weeks for term infants (ANOVA P = .0001).

CONCLUSIONS

We infer from this analysis that preterm infants are at higher risk for SIDS than term infants, and that the postconceptional age of peak vulnerability for SIDS may differ by 4 to 6 weeks between preterm and term infants.

Relationship of psychosocial status to low prenatal weight gain among nonobese black and white women delivering at term

OBJECTIVE

To examine the association of six indices of psychosocial well-being with low prenatal weight gain.

METHODS

Scales assessing depression, trait anxiety, stress, mastery, self-esteem, and social support were self-administered at mid-pregnancy to 536 black and 270 white low-income, nonobese, multiparous women who subsequently delivered at term. All women had one or more risk factors for fetal growth restriction. The association of individual scale scores with prenatal weight gain values below current Institute of Medicine guidelines was examined while controlling for sociodemographic and reproductive variables, and for time between last weight observation and delivery.

RESULTS

None of the scales were associated with low gain among black women. Among white women, poor scores (worst quartile) on four of the scales were associated with increased adjusted odds ratios for low gain, including 2.5 for high trait anxiety, 3.0 for increased levels of depression, 3.9 for low mastery, and 7.2 for low self-esteem. When scale scores and weight gain were examined as continuous variables, poor scores on five of the six scales were associated with lower weight gain values among white women (scores on the stress scale were the exception).

CONCLUSION

These data suggest an important role for psychosocial factors in the etiology of low prenatal weight gain among white women but show no such role for black women. Along with reports of wide inter-individual variability in the energy costs of pregnancy, these data also suggest that attempts to manipulate pregnancy weight gain through dietary means will meet with variable success until psychosocial and other factors affecting prenatal energy intake and/or utilization are further delineated.