Early and late growth and blood pressure in adolescence

OBJECTIVE

To assess the effect of growth during infancy and childhood on blood pressure in adolescence.

DESIGN

Birth cohort study.

SETTING

Pelotas, southern Brazil.

PARTICIPANTS

749 adolescents with complete information on birth weight and gestational age, as well as on anthropometric data at all three follow up visits (mean age 20 months, 42 months, and 15 years).

MAIN OUTCOME MEASUREMENTS

Systolic and diastolic blood pressure at adolescence.

RESULTS

After controlling for possible confounding variables, birth weight was negatively associated with systolic blood pressure, one unit increase in standard deviation score of birth weight for gestational age was associated with a decrease of 1.23 mm Hg (95% confidence intervals -2.03 to -0.43) in systolic blood pressure. Weight for age z score at the age of 15 years showed a strong positive association with systolic blood pressure, one unit increase in standard deviation score of birth weight for gestational age was associated with an increase of 4.4 mm Hg (95% confidence intervals 3.50 to 5.3). Diastolic blood pressure was not associated with birth weight. For adequate for gestational age infants, the positive association between weight in adolescence and blood pressure became stronger when previous weights were added to the model.

CONCLUSION

This study showed that early--as well as--late catch up growth is associated with increased systolic blood pressure in adolescence, whereas only late catch up is related with diastolic blood pressure. These findings suggest that catch up growth, irrespective of age, is associated with increased blood pressure in adolescence.

Comparison of two methods for assessing injuries among preschool children

BACKGROUND

Most studies of injuries use health services records or recall rather than prospective methods, and there is no information on how these different methods compare. This study was aimed at comparing a report (retrospective) with a diary (prospective) for recording childhood injuries.

METHODS

The study included 1,273 and 620 children, the retrospective and prospective subsamples, respectively, from a population based birth cohort in Pelotas, southern Brazil. The reported incidence of injuries in the preceding month were compared with those reported over month by diary (prospective study).

RESULTS

Both methods were well accepted and 92.7% of the diaries were returned. One or more injuries per child month were reported for 20.8% (retrospective) and 48.4% (prospective) of the children. The total number of reported injuries for the 620 children were 145 (retrospective) and 715 (prospective). Using the prospective method as the gold standard, the retrospective method detected only 20.2% of all injuries. Under-reporting did not vary significantly with maternal education, but was greater (51.8%) for injuries requiring medical care than for those managed at home (18.3%; p=0.003).

CONCLUSIONS

The diary was well accepted and resulted in higher incidences of reported injuries than the recall method, particularly for injuries that did not require medical care. Use of this method should be promoted to provide more complete epidemiological information to guide preventive strategies.

Short-term benefits of catch-up growth for small-for-gestational-age infants

BACKGROUND

Recent studies suggest that small newborns who present rapid postnatal growth may have an increased risk of chronic diseases in adulthood. On the other hand, it is widely assumed that catch-up growth is desirable for low birthweight children, but the literature on this subject is limited.

METHODS

Population-based cohort study in southern Brazil, with 3582 children examined at birth, 20 and 42 months of age. Catch-up growth from 0 to 20 months was related to subsequent risks of hospital admissions and mortality.

RESULTS

Children who were small-for-gestational-age (SGA) but presented substantial weight gain (> or =0.66 z-score) up to the age of 20 months had 65% fewer subsequent hospital admissions than other SGA children (5.6% versus 16.0%; P < 0.001). Mortality to age 5 years was 75% lower (3 versus 13 per 1000, a non-significant difference based on a small number of deaths) for rapid-growing SGA children compared to the remaining SGA children. Their admission and mortality rates were similar to those observed for children born with an appropriate birthweight for their gestational age (AGA). Similar positive effects of rapid growth were found for AGA children.

CONCLUSION

There appear to be definite benefits associated with catch-up growth. Growth promotion efforts for infants who are born small should take into account their possible short- and long-term consequences.

Ethnicity and infant health in Southern Brazil. A birth cohort study

BACKGROUND

Black children present more health problems than white children, but little information is available from less developed countries. Ethnic inequalities may vary according to country, and studies from developing countries are needed to evaluate possible differentials and their magnitude, and identify social and health interventions.

METHODS

Birth cohort study in Pelotas, Southern Brazil. Information collected during the perinatal period in hospitals, and at home at 1, 3, 6 and 12 months of age. In all, 5305 children were studied at birth, 96.8% of the sample of 1461 at 6 months, and 93.4% of this sample at 12 months of age.

RESULTS

Of the children, 28% were African Brazilian. Socioeconomic position was lower among families of black children, and mothers presented a number of unfavourable characteristics. Black children presented higher prevalences of low birthweight (LBW), preterm and small-for-gestational age (SGA), were less often immunized, had more deficits of weight-for-age and height-for-age, and higher early neonatal and infant mortality. When a number of covariates, including antenatal care, were added to a multiple regression analysis the odds ratios were markedly reduced, but there was still a clear trend towards worse results for black children. Black mothers had some aspects of antenatal care of lower quality and were submitted less frequently to caesarean sections and episiotomies.

CONCLUSIONS

Black infants experienced a much worse health status than white infants. Socioeconomic and other variables played a major role in determining inequalities between these ethnic groups. Antenatal care was especially important in explaining differentials in risk between black and white children.

[Health care of very low birth weight infants in Montevideo, Uruguay: a comparison between public and private sectors]

OBJECTIVE: To compare morbidity and mortality in very low birthweight infants admitted to public and private intensive care units in Montevideo, Uruguay. METHODS: Longitudinal design. All very low birth weight infants born in public hospitals of Montevideo between May 1st and October 31st, 1999, were included in the study and followed up until they were discharged from hospital, or died. The quality of care, and morbidity and mortality rates obtained in private intensive care units were compared with those observed in public intensive care units (infants who were never transferred). RESULTS: Of 141 infants, 19 were excluded from the study (13 died at the delivery room and six were transferred to intensive care units of other public hospitals). Of the remaining 122 infants, 61 were kept at the intensive care units of public hospitals, and 61 were transferred to a private unit. The infants who were transferred presented lower gestational age and increased neonatal depression. However, mortality among infants treated at intensive care units of public hospitals was twice as high (Hazard Ratio 1.8; 95%CI 1.1-3.4; P=0.04), especially in infants who weighed less than 1,000g (Hazard Ratio 2.4; 95%CI 1.1-5.5; P=0.04). CONCLUSIONS: The health status of very low birth weight infants treated at intensive care units of public and private hospitals in Montevideo, Uruguay, was assessed. Mortality was lower, and health care was better in neonatal units of private hospitals.

Infant mortality due to perinatal causes in Brazil: trends, regional patterns and possible interventions

CONTEXT

Brazilian infant and child mortality levels are not compatible with the country's economic potential. In this paper, we provide a description of levels and trends in infant mortality due to perinatal causes and malformations and assess the likely impact of changing intermediate-level determinants, many of which are amenable to direct interventions through the health or related sectors.

TYPE OF STUDY

Review paper.

METHODS

Two main sources of mortality data were used: indirect mortality estimates based on censuses and surveys, and rates based on registered deaths. The latter were corrected for under-registration. Combination of the two sources of data allowed the estimation of cause-specific mortality rates. Data on current coverage of preventive and curative interventions were mostly obtained from the 1996 Demographic and Health Survey. Other national household surveys and Ministry of Health Statistics were also used. A thorough review of the Brazilian literature on levels, trends and determinants of infant mortality led to the identification of a large number of papers and books. These provided the background for the analyses of risk factors and potential interventions.

RESULTS

The indirect infant mortality rate estimate for 1995-97 is of 37.5 deaths per thousand live births, about six times higher than in the lowest mortality countries in the world. Perinatal causes account for 57 % of all infant deaths, and congenital malformations are responsible for 11.2 % of these deaths. Mortality levels are highest in the Northeast and North, and lowest in the South and Southeast; the Center-West falls in between. Since surveys of the North region do not cover rural areas, mortality for this region may be underestimated.

CONCLUSIONS

A first priority for the further reduction in infant mortality in Brazil is to improve equality among regions, since the North and Northeast, and particularly rural areas, still show very high death rates. Further reductions in infant mortality will largely depend on decreasing deaths due to perinatal causes. Improvements in the coverage and particularly in the quality of antenatal and delivery care are urgently needed. Another intervention with a potential important impact on infant mortality is the promotion of family planning. Improving birth weight might lead to an 8 % reduction in infant mortality but the efficacy of available interventions is low.

The epidemiological transition in maternal and child health in a Brazilian city, 1982-93: a comparison of two population-based cohorts

Two studies carried out in 1982 and 1993 in the city of Pelotas, Southern Brazil, provide a unique opportunity for assessing the impact on maternal and child health of the economic and health care changes, which took place in Brazil in this period. The cohorts of mothers and infants of 1982 and 1993 were studied from the time of delivery. In both years, all mothers identified in the city's maternity hospitals answered a standardised questionnaire and their infants were examined. Over 99% of all children born in the city in each of the 2 years were included in the cohorts. Deaths occurring among these children were monitored prospectively, as well as all hospital admissions in the 1993 cohort. In the 1982 study, attempts were made to locate a 25% sample of the children at the mean age of 12 months using the addresses collected at the hospital (82% of the children were located), and all of the cohort children at the mean age of 20 months and 42 months, through a city census (87% were located in both follow-ups). In the 1993 study, 20% of all children plus all low birthweight infants were sought at 12 months of age, using the addresses collected at the hospital, and 95% were successfully traced. There was a 12% fall in the number of births occurring in 1993 (5,304 births), in comparison with 1982 (6,011 births), in spite of the increase in the population of reproductive age in the city during the decade. There was a marked difference in maternal height and weight at the beginning of pregnancy, with women giving birth in 1993 being, on average, 3.4 cm taller and 2.5 kg heavier than those who gave birth in 1982. The proportion of preterm babies (<37 weeks), measured by the date of last menstrual period, increased from 5.6% in 1982 to 7.5% in 1993. The median duration of breast feeding increased from 3.1 months in 1982 to 4.0 months in 1993. At 12 months of age, the prevalence of deficit of weight for age decreased from 5.4% in 1982 to 3.7% in 1993. The prevalence of deficit of height for age, however, increased from 5.3% to 6.1%. The perinatal mortality rate dropped 31%, from 32.2 per 1,000 births in 1982 to 22.1 deaths per 1,000 births in 1993. There was also a marked reduction in the infant mortality rate, from 36.4 per 1,000 livebirths in 1982 to 21.1 per 1,000 livebirths in 1993. The findings of the study indicate that there were improvements in the decade for most of the indicators evaluated, with the exception of birthweight and gestational age. It appears that improvements in perinatal and infant mortality rates are largely due to improvements in the health care sector.

Breast-feeding has a limited long-term effect on anthropometry and body composition of Brazilian mothers

The effect of lactation on maternal nutrition is controversial. Some studies have shown that breast-feeding reduces maternal weight, whereas some have not. All studies have been restricted to the first 2 y after delivery. We investigated the effect of lactation on maternal nutrition 5 y after delivery. All mothers giving birth in the city of Pelotas, Brazil, in 1993 were interviewed and weighed soon after delivery; information was also obtained on prepregnancy weight. In 1994, information on breast-feeding duration and pattern was collected for a 20% subsample. They were seen again in 1998, and those eligible (nonsmokers, no subsequent pregnancy, last birth weight > or = 2500 g) underwent measurements for weight, height, waist, hip and arm circumferences, triceps and subscapular skinfolds. The following indices were calculated in 312 women: body mass index, waist/hip ratio, arm fat area, the percentage of body fat assessed through skinfolds, and weight and body mass index change since before conception. The percentage of body fat was also measured through bioimpedance for half of the sample. After adjustment for confounding, all outcomes generally showed a similar pattern, i.e., mothers who breast-fed for 6-11.9 mo had lower measurements than those with shorter or longer durations. However, only the association with bioimpedance was significant (P < 0.03), and that for arm fat area tended to be significant (P = 0.06). Exclusive or predominant breastfeeding at 4 mo was associated with lower waist circumference (P = 0.05) and the percentage of body fat measured through skinfolds (P = 0.04). This study suggests that the relationship between breast-feeding and long-term changes in maternal weight is complex and, in this population, not particularly strong.

[Risk factors for suspicion of developmental delays at 12 months of age]

OBJECTIVE: To investigate the prevalence of positive screening test for developmental delays in a cohort of children born in Pelotas, Brazil in 1993, and their risk factors. METHODOLOGY: A sample of 20% (1,363 children) of a cohort of children born in Pelotas, Brazil, was studied at 12 months of age regarding their development. The Denver II Test was used. The children who failed in two or more items of the test were suspected of having development delay. A set of independent variables was chosen taking into account the hierarchical relations between risk factors according to the conceptual framework (socioeconomic, reproductive and environmental, birth conditions, childreńs care, nutrition and morbidity). Analyses were performed using Mantel-Haenszel X2 and multivariate technique through conditional logistic regression, to control for possible confounding. RESULTS: At 12 months of age, 34% (463) of the total of 1,363 children failed in the screening test. After adjusting for possible confounding variables, failure was associated with family lower income children (OR= 1.5), very low birth weight (OR= 4.0), gestational age less than 37 weeks (OR= 1.6), more than three siblings (OR= 1.9), and duration of breastfeeding less than three months (OR=1.6), or no breastfeeding (OR= 1.9). Children who presented weight/age at six months of age less or equal to -2 z score of the reference population presented a risk 10 times greater of having failure in the Denver II Test. CONCLUSIONS: This study reinforces the multiple etiology of development delays and the concept of cumulative risk effect. In this population those who are economically disadvantaged accumulate risk factors (social, economic and environmental) that may render to deficits in their development.

[Asthmatic children's risk factors for emergency room visits, Brazil]

OBJECTIVES

To study a sample of asthmatic children to get to know how the disease is managed by caretakers and to identify predictive factors associated with attendance in emergency room for asthma.

METHODS

A cross-sectional study nested in a cohort was undertaken in the urban area of Pelotas, Southern Brazil. 981 children aged 4-5 years, who belong to the cohort of 1993, participated in this study.

RESULTS

The asthma prevalence in the children sample was 25.4%. Morbidity for asthma was quite high: 31% of the children were seen in emergency rooms in the last year, 57% attended medical clinics and 26% were hospitalized in the first 4 years of life. The crude analysis identified the following predictive factors for emergency room visits: low educational level (RO=4.1), low family income (RO=6. 5), 3 or more children sleeping in the same room (RO=2.2), severity of asthma attacks (RO=2.7), use of asthma medicines in the last year (RO=1.9) and hospitalizations due to asthma (RO=3.0). Multivariate analyses using logistic regression were used to adjust each variable for the effect of the remainder.

CONCLUSIONS

The asthma prevalence among preschool children in Pelotas is high, resulting therefore in high morbidity. The predictor factors for emergency room visits due to asthma found, after multivariate analysis, were mother's low educational level, severity of the asthma attacks and hospitalization.

[Diagnosis of overweight in adolescents: comparative study of the performance different criteria for body mass index]

OBJECTIVE

In an attempt to simplify the screening process for detecting obesity in adolescence, the performance of different cutoff values for body mass index (BMI) was assessed in a population-based cohort in Southern Brazil.

METHODS

A total of 493 adolescents aged 15-16 years who lived in the city of Pelotas, Brazil, were studied. Obesity was defined according to the WHO criteria taking into account age and sex (a BMI equal to or greater than the 85th percentile of the NHANES I reference, plus subscapular and triceps skinfold equal to or greater than the 90th percentile of the same reference). Different BMI cutoff values were used to assess their specificity and sensitivity.

RESULTS

For boys, BMI>/=25 kg/m(2) showed the best performance for detecting obesity, with a sensitivity of 90% and only 5% of false positives. The Brazilian proposed criteria that was used had 100% sensitivity but up to 23% of false positives. Higher cutoff values were also tested, but there was a slight increase in specificity, accompanied by a marked reduction in sensitivity.

CONCLUSIONS

The BMI cutoff of 25 kg/m(2) presented the best performance for screening obesity in the studied sample, and it is recommended for adolescents aged 15 and more in populations with similar characteristics. It provides a single cutoff value to be used in primary health services, eliminating the need for age and sex-specific values and skinfold measurements, and it is also consistent with the cutoff value proposed to identifying overweight adults.

[Hospitalization for bronchiolitis: a risk factor for recurrent wheezing]

This longitudinal study evaluated the role of hospitalization for acute bronchiolitis as a risk factor for recurrent wheezing. Participants were children from a 1993 cohort in a southern Brazilian city. Hierarchical multivariate analysis showed that previous hospitalization for bronchiolitis was the most important risk factor for recurrent wheezing, with an odds ratio of 4.9. This strong association is consistent with a casual relationship hypothesis.

Explaining trends in inequities: evidence from Brazilian child health studies

There is considerable international concern that child-health inequities seem to be getting worse between and within richer and poorer countries. The "inverse equity hypothesis" is proposed to explain how such health inequities may get worse, remain the same, or improve over time. We postulate that as new public-health interventions and programmes initially reach those of higher socioeconomic status and only later affect the poor, there are early increases in inequity ratios for coverage, morbidity, and mortality indicators. Inequities only improve later when the rich have achieved new minimum achievable levels for morbidity and mortality and the poor gain greater access to the interventions. The hypothesis was examined using three epidemiological data sets for time trends in child-health inequities within Brazil. Time trends for inequity ratios for morbidity and mortality, which were consistent with the hypothesis, showed both improvements and deterioration over time, despite the indicators showing absolute improvements in health status between rich and poor.

[Maternal nutrition and duration of breastfeeding in a birth cohort in Pelotas, Brazil]

OBJECTIVE

The effects of maternal nutritional status on the duration of breastfeeding are inconsistent in the literature. A population-based cohort study was set to investigate this relationship.

METHODS

Nine hundred and seventy seven mothers giving birth in 1993 (20% of that year's births) were studied. Studied maternal characteristics included nutritional status, social, economic, and demographic variables. The effects of these variables on the prevalence of breastfeeding at six months were analyzed through logistic regression. Cox regression was applied to analyze the effects on the duration of breastfeeding.

RESULTS

Multivariate logistic regression analysis showed a higher prevalence of breastfeeding among women with a pre-pregnancy weight of 49 kg or more (odds ratio = 1.31; CI(95%) 1.04 - 1.64). The association with maternal height was not significant (p=0.06). Cox regression also showed a non-significant protective effect of having a higher pre-pregnancy weight (hazard ratio = 0.91; CI(95%) 0.82 - 1.01). The duration of breastfeeding duration was not associated with maternal height. Weight gain during pregnancy was not associated with breastfeeding in either analyses. Other variables associated with the duration of breastfeeding in both analyses were maternal age, parity, smoking, and gestational age. Family income was associated with the prevalence of breastfeeding at six months, and birthweight was associated with the duration of breastfeeding.

CONCLUSIONS

Pre-pregnancy nutritional status is a stronger predictor of breastfeeding than weight gain during pregnancy.

Rates and implications of caesarean sections in Latin America: ecological study

OBJECTIVES

To estimate the incidences of caesarean sections in Latin American countries and correlate these with socioeconomic, demographic, and healthcare variables.

DESIGN

Descriptive and ecological study.

SETTING

19 Latin American countries.

MAIN OUTCOME MEASURES

National estimates of caesarean section rates in each country.

RESULTS

Seven countries had caesarean section rates below 15%. The remaining 12 countries had rates above 15% (range 16.8% to 40.0%). These 12 countries account for 81% of the deliveries in the region. A positive and significant correlation was observed between the gross national product per capita and rate of caesarean section (r(s)=0.746), and higher rates were observed in private hospitals than in public ones. Taking 15% as a medically justified accepted rate, over 850 000 unnecessary caesarean sections are performed each year in the region.

CONCLUSIONS

The reported figures represent an unnecessary increased risk for young women and their babies. From the economic perspective, this is a burden to health systems that work with limited budgets.

Increased blood pressure in adolescents who were small for gestational age at birth: a cohort study in Brazil

BACKGROUND

This paper studies the relationship between birthweight for gestational age and blood pressure in adolescents aged 14-15 years in southern Brazil.

METHODS

A sample of 1076 adolescents belonging to a cohort of over 6000 children born in 1982 in Pelotas, southern Brazil, was studied in 1997. All households in a sample of 25% of the city's census tracts were visited and all adolescents born in 1982 were interviewed, weighed, and their blood pressures were measured twice. Data from the adolescents were linked to the database through their names and dates of births.

RESULTS

High diastolic and systolic pressure (defined as >95th percentile) were significantly more frequent among adolescents who were born below the 10th percentile of birthweight for gestational age. No association was found between high blood pressure and low birthweight or preterm births. In a multiple linear regression analysis, the association between birthweight for gestational age and blood pressure was not statistically significant after adjusting for age, sex, skin colour and family income. However, when the current body mass index and height were added to the model both diastolic and systolic pressure were significantly associated with birthweight for gestational age, and adolescents who were small for gestational age at birth presented a mean elevation of 3.08 mmHg for diastolic pressure and 2.89 mmHg for systolic pressure.

CONCLUSIONS

There is an inverse association between birthweight for gestational age and blood pressure during adolescence. This association, however, is only disclosed when the negative confounding effect of the body mass index is controlled for. The same association is not found when the effects of birthweight and gestational age on blood pressure are analysed separately. It appears therefore that the elevation of blood pressure during adolescence only occurs when there was intra-uterine growth retardation.

Impact of breast feeding on admission for pneumonia during postneonatal period in Brazil: nested case-control study

OBJECTIVE

To determine whether breast feeding protects infants against pneumonia and whether the protection varies with age.

DESIGN

Nested case-control study.

SETTING

Pelotas, southern Brazil.

SUBJECTS

Cases were 152 infants aged 28-364 days who had been admitted to hospital for pneumonia. Controls were 2391 cases in a population based case-control study.

MAIN OUTCOME MEASURE

Odds ratio of admission for pneumonia according to type of milk consumed (breast milk alone, breast and formula milk, or formula milk and other fluids only), use of fluid supplements apart from formula milk, and use of solid supplements.

RESULTS

Infants who were not being breast fed were 17 times more likely than those being breast fed without formula milk to be admitted to hospital for pneumonia (95% confidence interval 7.7 to 36.0). This relative risk was 61 (19.0 to 195.5) for children under 3 months old, decreasing to 10 (2.8 to 36. 2) thereafter. Supplementation with solids was associated with a relative risk of 13.4 (7.6 to 23.5) for all infants and 175 (21.8 to 1405.1) for those under 3 months old.

CONCLUSION

Breast feeding protects young children against pneumonia, especially in the first months of life. These results may be used for targeting intervention campaigns at the most vulnerable age groups.

[Epidemiology of drug use during the first three months of life in a urban area of southern Brazil]

INTRODUCTION

The few studies on the use of medicines in children point to excessive use, and in these studies, physicians are those mainly responsible for the prescription of medicines. In order to get to know the patterns of consumption medicines better, a study was made in children in their first three months of life, according to social biological, food pattern and use of health services of variables.

METHOD

The patterns of the use of medicines during the first three months of life in 655 urban children born in Pelotas, Brazil, in 1993, were described. Information on the use of medicines was collected during a two-week period in the first and third month of life.

RESULTS

The use of medicines was reported by 65% of mothers at the 1st and 69% at the 3rd month of life. Seventeen per cent of children consumed three or more different medicines during those periods. Fixed combinations of three or more components-which was taken as an indicator of the poor of medicines quality-were consumed by 14% of the children at the 1st and 19% at the 3rd months of life. At the latter age, 20% of children had used a given medicine for one month or more. At the first month follow-up, Benzalkonium Chloride + Normal Saline Solution (nasal drops), Nystatin Mixture and Dimethicone + Homotropine were the most frequently used medicines. At the third month they were, Aspirin, Benzalkonium Chloride + Normal Saline Solution and Dimethicone + Homatropine. The main reasons for taking medicines were cramps at the first month and colds at the third. At the first month follow-up, children with three or more siblings used 64% less medicines than the older ones. Children who were not breast-fed at the end of the first month showed a 75% greater risk of use of medicines. Similar results were observed at the third month follow-up. Some of the medicines used were not recommendable for children.

CONCLUSION

Since early age children are submitted to an intense use of medicines for almost every conceivable reason, with the risk of potential side-effects and the possible lead to medicine or other drugs addiction.

The NCHS reference and the growth of breast- and bottle-fed infants

The current international growth reference, the National Center for Health Statistics (NCHS) reference, is widely used to compare the nutritional status of populations and to assess the growth of individual children throughout the world. Recently, concerns were raised regarding the adequacy of this reference for assessing the growth of breast-fed infants. We used the NCHS reference to evaluate infant growth in one of the most developed areas of Brazil. Infants who were exclusively or predominantly breast-fed for the first 4-6 mo, and partially breast-fed thereafter, grew more rapidly than the NCHS reference in weight and length during the first 3 mo, but appeared to falter thereafter. The average growth of all infants, regardless of feeding pattern, was faster than the NCHS reference until approximately 6 mo, after which their growth became slower than that of the NCHS sample. To substantiate this finding, the NCHS growth curves were then compared with growth data of breast-fed infants in developed countries from pooled published studies, formula-fed North American and European infants and predominantly bottle-fed U.S. infants monitored by the Centers for Disease Control and Prevention (CDC) Pediatric Surveillance System. In all three cases, weights showed the same pattern as the Brazilian infants-higher than NCHS in the early months but an apparent decline thereafter. The pattern for length gain was similar but less marked. Breast-fed infants showed more pronounced declines than those who were predominantly bottle-fed. These findings suggest that the infancy portion of the NCHS reference does not adequately reflect the growth of either breast-fed or artificially fed infants. This probably results from characteristics of the original sample and from inadequate curve-fitting procedures. The development of an improved international growth reference that reflects the normal infant growth pattern is indicated.

[Prenatal care in Pelotas, Rio Grande do Sul, Brazil, 1993]

All 5304 births in the hospitals of Pelotas, Rio Grande do Sul, Brazil in 1993 were studied. Neonates were examined and their mothers were interviewed regarding sociodemographic conditions, family income, reproductive health, and medical care during pregnancy. Ninety-five per cent of women received prenatal care. The mean number of physician visits during pregnancy was 7 and the majority of the women (84.7%) began visits before the fifth month of pregnancy. Women who did not receive prenatal care were from the lowest socioeconomic stratum and were mostly adolescents or over 40 years of age. Incidence of low birth weight in this group was 2.5 times that of the group with more than five visits (p>0.001). Perinatal mortality rate was 50.6/1000 in the group without prenatal care and 15.8/1000 in the group with more than five visits. With regard to utilization of health care, the study shows that twenty-five per cent of women with high gestational risk received inadequate prenatal care. The rate was less than 10% in the group of women with low gestational risk. These results suggest the need for improvement in the quality of prenatal care with special attention for mothers with high gestational risk.

[Risk factors for perinatal mortality in Pelotas, a southern city of Brazil, 1993]

INTRODUCTION

Although there was a considerable reduction in infant mortality in Pelotas, Rio Grande do Sul in the last decade, its perinatal causes were reduced only by 28%. The associated factors of these causes were analysed.

MATERIAL AND METHOD

All hospital births and perinatal deaths were assessed by daily visits to all the maternity hospitals in the city, throughout 1993 and including the first week of 1994.

RESULTS

The perinatal mortality rate was 22.1 per thousand births. The multivariate analysis showed the following risk factors: low socioeconomic level, male sex and maternal age above 35 years. Among multigravidae women, the fetal mortality rate was significantly increased for mothers with a previously low birthweight and a previous stillbirth. For early neonatal mortality the risk was significantly increased by a smaller number of antenatal visits than 5 and low birthweight.

CONCLUSIONS

Main risk factors for perinatal mortality: low socioeconomic level, maternal age above 35 years and male sex. For early neonatal mortality the risk was significantly increased by a smaller number of antenatal visits than 5 and low birthweight.

[Incidence and duration of breast-feeding by type of delivery: a longitudinal study in southeastern of Brazil]

OBJECTIVE

To compare the incidence of breastfeeding according to type of delivery.

METHODOLOGY

Population-based cohort study of 655 children born in 1993 and followed up during the first three months of life through home visits.

RESULTS

Breastfeeding duration was similar among babies born either by vaginal delivery or by emergency cesarean section. Babies born by elective cesarean section, however, presented a three times higher risk of stopping breastfeeding in the first month of life, after adjusting for possible confounding factors (odds ratio = 3.09; 95% CI 1.3-7.2). The increased risk did not persist into the third month of life.

CONCLUSIONS

It is recommended that health services pay special attention, in the promotion of breastfeeding, to babies born by elective cesarean section, as a way to avoid early weaning.