Predicting birth weight by fetal upper-arm volume with use of three-dimensional ultrasonography

OBJECTIVE

Our purpose was to determine the usefulness and accuracy of the three-dimensional ultrasonography assessed fetal upper-arm volume in predicting birth weight.

STUDY DESIGN

From June 1996 to October 1996, we performed a prospective study of ultrasonography on 105 pregnant women without fetal structural anomaly or aneuploidy. Both the traditional two-dimensional ultrasonographic parameters and three-dimensional ultrasonography for fetal upper arm volume were measured within 48 hours of delivery.

RESULTS

The upper arm volume correlated well with birth weight (r = 0.92, n = 105, p < 0.0001). With use of linear and polynomial regression, we obtained a best-fit new formula, Birth weight = 1088.60 + 36.024 x Upper-arm volume. The accuracy of this new formula is compared with that of two Chinese equations predicting fetal weight reported before and other formulas commonly used in the world as well. Our formula is more accurate in predicting birth weight than all the other formulas by traditional two-dimensional ultrasonography, either in error, percentage error, or absolute error. Another group by prospective validation further proved this finding.

CONCLUSION

The upper-arm volume assessed by three-dimensional ultrasonography can accurately predict birth weight, and its accuracy is superior to the previous, formulas. Our study has at least validated the application of upper-arm volume by three-dimensional ultrasonography in estimating fetal weight. Further larger series are needed to confirm our findings.

Impact of nutrition education on health of the mother and newborn belonging to the poor urban slum community

To find the nutritional knowledge among mothers of one child of the poor community and to relate status of education to the nutritional health of them and the newborn and to get a thorough knowledge on the impact of nutritional education, a comprehensive study was undertaken in an urban slum area. Nutritional grading was done through scoring system. There were 47 mothers (24.1%) out of 195 having normal nutritional grade and 37 mothers (19%) having severe nutritional grade. There were 80 mothers having 'no knowledge' on maternal nutrition. 'Adequate knowledge' was found in 31 cases. Mothers (n = 80) of 'no knowledge' delivered babies of average weight 2.3 kg whereas 'adequate knowledge' mothers gave birth to babies of average weight 2.9 kg.

Maternal anthropometry and infant feeding practices in Israel in relation to growth in infancy: the North African Infant Feeding Study

Relations between maternal anthropometric status during pregnancy and infant feeding practices and growth from birth through the first 6 mo of life were examined in a cohort of 351 Israeli mother-infant pairs of North African descent. Maternal weight, height, and triceps skinfold thicknesses were determined at 6 and 9 mo of pregnancy, while infants' weights and lengths were measured at birth and at 1, 2, 3, and 6 mo of age with concurrent collection of age-specific maternal-reported infant feeding data. On the basis of multiple-linear-regression analysis that adjusted for potential covariates, mean maternal weight at the first prenatal visit and at 6 and 9 mo of pregnancy were positively associated with birth length (P for trend in all cases < 0.0001) and with linear growth between birth and 1, 3, and 6 mo of age. Maternal skinfold thickness at 9 mo of pregnancy and maternal height were also significantly associated with birth length. Moreover, maternal height, weight, and skinfold thickness at 6 and 9 mo of pregnancy were positively associated with mean birth weight. After adjustment for morbidity in the past month and other covariates, infants breast-fed exclusively had greater attained weight and weight gain in the first 3 mo compared with infants who were bottle-fed exclusively, breast-fed and bottle-fed, or solid-fed exclusively. These findings underscore the need for programs that improve the nutritional status of women before, during, and after pregnancy, and encourage exclusive breast-feeding of infants for at least the first 3 mo of life.

Prediction of birth weights from body weights of newborns

OBJECTIVE

To evaluate the accuracy of prediction of birth weights from body weights of newborns till six days after birth.

DESIGN

Prospective follow-up.

SETTING

Four villages near Hyderabad.

METHODS

Weights of 47 newborns were recorded daily from the day of birth for seven days. The birth weights were regressed on the weights of the babies taken on the 2nd day to the 7th day. Specificity and sensitivity of the predicted birth weights to arrive at the prevalence of low birth weight (LBW) were computed.

RESULTS

The co-efficient of determination (R-square) for between the days measurements decreased from 95% on the second day to 86% on seventh day with an increase in the standard error of the estimate from 84 g to 154 g. Based on the "predicted birth weights", the prevalence of LBW in the community was arrived at and compared with the actual observation. The sensitivity and specificity of these regression equations was high and ranged from 0.95 to 0.85 and 0.96 to 0.93, respectively.

CONCLUSIONS

In situations where the birth weight cannot be recorded, weight of the baby taken within the first week after birth may be reliably utilized to assess the "birth weight", particularly in relation to categorization as LBW. This methodology can serve as a tool to monitor various developmental programs aimed at improving birth weights.

Maternal determinants of birth weight: a population-based sample from Qingdao, China

This analysis examines the relationship between maternal determinants and birth weight in a population-based birth cohort of 5,284 mothers with singleton births of 28 completed gestational weeks in Qingdao, China, in 1992. Multiple linear regression models suggest that the length of the menstrual cycle, age at menarche, maternal weight, maternal height, parity, and number of antenatal visits had independent effects on birth weight after controlling for gestational age and sex of infant. The estimated difference in mean birth weight for each year after menarche was 11.7 g (95 per cent CI 4.6-18.8), and for each day of the menstrual cycle was 4.0 g (95 per cent CI, 2.1-6.0), after controlling for gestational age, sex of infant, maternal height, maternal weight, parity and the number of antenatal visits. No substantial differences in determinants of birth weight were found between the sexes. Maternal age, education, and occupation failed to reveal any significant association with birth weight. In sum, those women who reached menarche younger and had a relatively short menstrual cycle had a heavier baby on average, and the determinants of birth weight did not differ between male and female in the cohort.

Birthweight and sociobiological factors in Ilorin, Nigeria

Social and biological factors influencing birthweight of 3053 Ilorin babies were studied. The mean birth weights were 2.998 kg +/- 0.133 (SD) for males and 2.932 kg +/- 0.154 (SD) for females. Multiple regression analysis showed that maternal weight, height, age, education and ethnicity, and child's sex, significantly affected birthweight of infants. Some quadratic and interaction terms also contributed significantly to the prediction of birthweight. The strategies to control the incidence of low birth weight are discussed.

A comparison of seasonal variation in birthweights between rural Zaire and Ontario

We studied the birthweights in a rural area in Zaire over a ten-year period and found a significant seasonal variation. Also, we reviewed the birthweights in two areas of Ontario over a five-year period. One area was in an Ontario Metropolitan hospital doing more than 2000 deliveries per year. The other was in a rural area in southwestern Ontario doing about 500 deliveries per year. No statistically significant seasonal variation in birthweight was found in Ontario. The seasonal variation in Zaire was associated with change in expenditure of energy by the pregnant women, variation in food availability, and malaria.

Birthweight and socioeconomic status: a study in Kigali, Rwanda

Data were collected on 6709 singleton livebirths occurring in the hospital of Kigali, Rwanda. An analysis of birthweights was carried out by socioeconomic status, parity and age of the mother. The mean birthweight was highest in the high socioeconomic group. An effect of maternal age and parity on birthweight was observed. Because of the strong association between socioeconomic status and birthweight, the incidence of low birthweight can be used as an indicator of socioeconomic development.

Adolescent maternal weight gain and low birth weight: a multifactorial model

Maternal weight gain is one of the most important independent predictors of infant birth weight and interacts with other maternal characteristics, including age, so that infant birth weight reaches a plateau at a higher level of maternal weight gain for young adolescents than for adults. It has been suggested that encouraging young adolescents to gain larger amounts of weight during pregnancy may be one way to decrease their risk of low-birth-weight deliveries. This recommendation may be premature because the mechanisms underlying the interaction between maternal age and weight gain are incompletely understood and may include such diverse factors as incomplete maternal growth, reproductive immaturity, diminished maternal body size, nutritional deficiencies, socioeconomic and behavioral factors, and maternal emotional stress. This review summarizes the literature on adolescent maternal weight gain and infant birth weight and discusses the importance of considering a multifactorial model in reformulating the weight-gain recommendations for pregnant adolescents.

Influence of young maternal age and parity on term and preterm low birthweight

Data on 4496 singleton births to young women (19 years or less) are reported by maternal age and parity with birthweight and gestation cross-classified to yield rates of preterm and term low birthweight. After adjustment, the risk of preterm low birthweight was increased with very young maternity (15 years or less); preterm low birthweight and term low birthweight were each increased with young multiparity. These data suggest that the identification of factors associated with preterm birth and their incorporation into the prenatal care regimen may be important in improving pregnancy outcome in young women.

Cigarette smoking, alcohol consumption and fetal outcome in Tasmania 1981-82

Analysis of cigarette smoking and alcohol consumption patterns recorded in pregnancy could not detect a harmful effect of alcohol at levels below 2 glasses a day. Total abstainers fared very slightly worse than those who drank occasionally. Smoking was associated with lower birth-weight and a worse fetal outcome independent of socioeconomic status, parity, maternal age or alcohol consumption. There was evidence of an interaction between smoking and adverse social and parity factors in low birth-weight.

Smoking and pregnancy

Smoking during pregnancy is associated with many adverse outcomes, including fetal and neonatal death. These consequences are tragic in many ways, but perhaps the greatest tragedy is that they are preventable if the smoker ceases to smoke during pregnancy. Although in some instances the so-called constitutional hypothesis is difficult to disprove, the available evidence seems more than convincing that it is smoking itself, and not the smoker's unique constitution, that is responsible. Cessation from smoking is clearly advisable at any time, but more so during pregnancy when every cigarette affects both the smoker and her unborn child.

Factors affecting birthweights in Hindus, Moslems and Europeans

The birthweights of 664 Hindu and 132 Moslem babies were compared with those of 486 European babies born at the same hospital. The mean birthweight of the Europeans was 3362 g, compared with 3146 g for the Moslems and 2960 g for the Hindus. The Asian women were smaller than the European and tended to have a shorter length of gestation. Forty-four per cent of the Asians and 46% of the European mothers were of social classes I and II; 28% of the Europeans and 2% of the Asians smoked. There were no significant differences between Asians and Europeans in the effects of maternal size, parity, gestational age and fetal sex on birthweight. After adjustment for these variables and for cigarette smoking there was no significant difference in birthweight between the Moslems and the Europeans, but the mean birthweight of the Hindus was about 190 g lighter than that of the Europeans. Hindus from East Africa had lighter babies than those from India.

Rainfall and birthweight distribution in rural Tanzania

Seasonal variations in birthweights over a 10-year period are compared with the local rainfall pattern in a rural area of Tanzania. Mean birthweight falls by about 60 g in the course of the rainy season. Lagged regression analysis reveals a negative impact of rainfall on birthweight after 3 months. Deviations from average rainfall show a positive correlation with birthweight after 4 months, but only in the months when rainfall is critical for food crop production. The interactions of these contrary effects are held responsible for the sudden fluctuations in mean birthweight that were observed.

Maternal nutritional status and adolescent pregnancy outcome

To investigate the determinants of low birth weight of infants born to adolescent mothers, we studied the obstetric population attended at the Maternity Hospital of Lima, Peru. From this population we selected for study a sample of 1256 adolescent mothers ranging in age from 12 to 25 yr. The study included anthropometric and biochemical measurements used to evaluate nutritional status and physiological maturity of the mother and newborn. Findings from the present research indicate that the low birth weight of infants born to adolescent mothers is not due to premature delivery (short gestation) or low gynecological maturity. Furthermore, young adolescent mothers had smaller and thinner newborns than those born to older women who were adjusted for nutritional status during pregnancy and at delivery. That is, despite the similar nutritional status among the young adolescent mothers, the availability of nutrients for the accumulation of calories in the fetus (measured by skinfold thickness) was less than that of older women. Furthermore, the pregnancy weight gain associated with an optimal or average newborn weight is greater for young teenagers than for older women. These findings support the hypothesis that among rapidly growing teenagers the nutritional requirements of pregnancy may be greater than those of older women, and that this increased requirement competes with the growth needs of the fetus.