[Breastfeeding prevalence during the first year of life in Aragon. CALINA study]

OBJECTIVES

To study the current prevalence of breastfeeding (BF) in Aragon (Spain) during the first 12 months of life, and analyse its demographic, perinatal and social influential factors.

MATERIAL AND METHODS

Obstetric, perinatal and feeding aspects were evaluated in a longitudinal and observational study, in a representative cohort of infant population from Aragon born between March 2009 to March 2010, controlled until 12 months of age (N=1.602).

RESULTS

Exclusive or predominant BF was more frequent than the rest of feeding modalities during the first 4 months of life. Maintenance prevalence of any BF modality was 82.5% at 1(st) month of age, 71.8% at 3(rd), 54.3% at 6(th), and 27.8% at 12 months of age. Maternal variables that were significantly associated with BF maintenance both at 1 and 6 months of age were: delivery modality (higher probability in case of vaginal delivery), academic level (higher probability if university studies), origin (higher probability in mothers from Africa), adiposity (higher probability of normal weight or overweight mothers compared with obese ones), and not to smoke during gestation.

CONCLUSIONS

BF prevalence in Aragon (Spain) during the first 12 months of age is high and has increased compared with previous data. BF continues in more than half of infants at six months and in a quarter of infants at 12 months of age. Maternal factors that significantly influence BF initiation and maintenance are, delivery modality, academic level, origin (immigration), adiposity and smoking habit.

[To born small for gestational age may depend on the growth curve used]

INTRODUCTION AND OBJECTIVE

Population standards of intrauterine growth are necessary to evaluate if the newborn has grown well, if their nutritional conditions are appropriate and to identify groups at risk as those small for gestational age (SGA). Differences in the number of SGA newborns identified, depending on the standard applied, have been analyzed in this study.

MATERIAL AND METHODS

Cross-sectional study conducted in 4,486 Caucasian newborns (2,361 boys and 2,125 girls), born between 35 and 41 weeks. Weight and length valuation was performed following the standard methodology. Percentage of children under the 10(th) percentile for weight and length was calculated depending on the standard used (Olsen et al. 2010, Lubchenco et al. 1966, Delgado et al. 1996, Carrascosa et al. 2008), being diagnosed of SGA.

RESULTS

Weight and length were significantly higher in boys than in girls at all ages. 10(th) percentile values defined for every gestational age are globally similar among the different standards and our population, with the clear exception of Lubchenco curves whose 10(th) percentile values are even 300 g. lower for the newborns at the highest gestational ages. Lubchenco charts do not fit the pattern of intrauterine growth of our population and identify a smaller number of SGA. The percentage of SGA of our sample ranged between 1.7% and 14% in depending on the standard, sex and gestational age considered.

CONCLUSION

The number of children classified as SGA is different according to each standard used. Lubchenco charts identify a smaller number of SGA than the others. The rest of curves show similar values and seem to be well adapted for our population. The correct identification of SGA will allow a better assessment of short and long-term risks of these newborns.

[Nutritional characteristics of newborns of overweight and obese mothers]

INTRODUCTION

Maternal nutritional status is an important factor of adequate intrauterine growth and neonatal weight. The aim of this study is to evaluate the relationship between pre-gestational BMI (Body Mass Index) and breastfeeding duration, as well as infant anthropometric measurements during their first six months of life.

MATERIALS AND METHODS

Anthropometric measurements and the type of feeding were evaluated in a representative sample of 1,547 newborns from our population during 2009, according to their maternal BMI, and also in a sub-cohort of 759 infants followed up to 6 months of life.

RESULTS

A total of 72.9% of women had a normal weight, 18.7% were overweight and 8.4% obese. Women with a BMI ≥ 25 kg/m(2) had lower weight gain during pregnancy (P < .001), lower socioeconomic and cultural level (P < .001), and their infants had higher weight at delivery (P=.003) and at 6 months of life, with no differences in body length. Newborn weight increased in relation to maternal BMI, but over 35 kg/m(2) it decreased progressively (P < .001). Breastfeeding prevalence in obese women was 58.5% at hospital postpartum discharge, and 8.6% at six months of life; as opposed to 70.8% and 13.9%, respectively in women with normal BMI.

CONCLUSIONS

In our sample, maternal obesity is associated with a low socioeconomic and cultural level, higher infant weight at delivery and at 6 months of life, and less prevalence of exclusive breastfeeding; all of them nutritional risk factors in the short and long term.

[Brachial measurements as nutritional indicators in health term newborns]

OBJECTIVE

Our objective was to study the correlations between weight and length and weight index and brachial areas in healthy term newborns as indicators of nutritional status.

PATIENTS AND METHODS

We studied 794 consecutive Caucasian newborns, 377 male and 417 females, with gestational ages of 39 +/- 09 weeks and adequate weights. We measured weight, length, weight/length index, body mass index and weight index. Measurements of the arm perimeter and tricipital skinfold were used to calculate the fatty, lean and total areas by two different methods. Mean, standard deviation and percentiles were utilized in the measurements. The Student's t-test was used to calculate differences and Pearson's test for correlations.

RESULTS

We found that weight, length and weight/length indexes were higher in males than in females, except for the weight index. Brachial areas and parameter were higher in females, except for the lean area. We did not find significant differences between gender in brachial measurements calculated by the different methods. Among the males, we found a high degree of correlation between weight and the weight/length index (r = 0.963; p < 0.0001), and weight and total body area (r = 0.649; p < 0.0001). Similar data were obtained among females, where in addition a high correlation was found between the fat percentage and the body mass index (BMI, r = 0.223; p < 0.0001), as well as between brachial areas and BMI in both genders (p < 0.0001).

CONCLUSIONS

In normal newborns, the brachial areas, taken as indicators of body composition, are statistically significantly correlated with the anthropometric parameters widely used to measure the nutritional status of newborns.

[Anthropometric and nutritional study of full-term newborns. Evaluation of the submandibular adipose skinfold]

OBJECTIVE

We performed an anthropometric study in a series of normal full-term newborns to evaluate the discriminatory capabilities of the submandibular skinfold compared to other anthropometric parameters.

MATERIAL AND METHODS

We studied 794 consecutive Caucasian newborns, 377 males and 471 females, with a mean gestational age of 39.5 +/- 0.9 weeks and adequate weights for age. Anthropometric variables analyzed included weight, length, left arm circumference and bicipital, tricipital, subscapular, suprailiac and submandibular skinfolds. Statistical analysis was performed by using the Student's t-test to evaluate differences between the different parameters and by Pearson's test to look for correlations among them.

RESULTS

The weight and lengths of male newborns were significantly higher than those of female newborns (p < 0.005) These parameters showed differences with other series of newborns studied. Measurements of the tricipital, subscapular and suprailiac skinfolds were significantly different between males and females (p < 0.005); however, bicipital and submandibular skinfolds were not. The submandibular skinfold measurement highly correlated with the other skinfold measurements, especially with the bicipital measurement, in both males (0.536; p < 0.0001) and females (0.578; p < 0.001). Submandibular skinfold measurements also correlated with weight and arm circumference in both sexes.

CONCLUSIONS

Some somatometric measurements in normal term newborns differ significantly between the sexes, especially weight, length and tricipital, subscapular and suprailiac skinfolds. The submandibular skinfold correlates well with weight, arm circumference and the four routinely measured skinfolds. This finding suggests that measurement of the submandibular skinfold should be included in the evaluation of the newborn's nutritional status.

[Quantification of heart rate variability in newborn infants and during the first 6 months of age]

We have registered, on 36 normal newborns at term, ECG recordings of sixty seconds at a speed of 100 mm/second, from birth tooth sixth month of postnatal life. The heart rate variability was measured on its double slope, short and long term by the numerical method that Yeh proposed, consistent with the "differential index" (DI) and the "interval index" (II). For the short term variability, we have obtained minimum values at birth and maximum values at 72 hours of postnatal life, with a tendency to drop up to the end of the first month and later to become stable until the end of six months of age. The changes found among different ages, could be related to modifications in basal heart rate under autonomic nervous system control. The variability values of the long term, do not show a clear age relation.