Growth and sexual maturation of low birth weight children: a 14 year follow up.

OBJECTIVE: To evaluate the physical growth and sexual maturation of children born with low birth weight (< 2000 g). (LBW). DESIGN: Longitudinal follow up. SETTING: Hospital born urban cohort. METHODS: Weight, height, head circumference and pubertal changes were recorded till 14 years at specified intervals in 252 LBW and 176 control (term neonates with birth weights > or = 2500 g) children. Effect of prematurity and fetal growth retardation (SFD) was studied in 79 preterm appropriate for gestation and 45 term SFD children. RESULTS: LBW boys significantly lagged behind their controls for all physical growth parameters till 14 years, while the LBW girls had a physical growth comparable to controls after 11 years. Preterms had comparable weight, height and head circumference with their controls after 11 years. The SFDs, however, remained significantly handicapped in their overall physical growth even at 14 years. In comparison to controls, menarche occured 6 months earlier in preterms and 12 months earlier in SFD girls. However, there was no change in the sequence of pubertal changes in either preterms or SFDs. CONCLUSIONS: Fetal growth retardation has a lasting adverse effect on later physical growth, while most preterms catch up with their peers by adolescence.

Intrauterine growth predictors.

The present study was conducted to construct standards for midarm circumference and midarm/head circumference ratio to identify neonates at risk for metabolic complications and to assess the anthropometric variable which could be used to substitute weight to identify low birth weight neonates. A study of 2925 consecutive live births showed significant correlation (p less than or equal to 0.001) between different anthropometric variables studied. Since midarm circumference (MAC), midarm circumference/head circumference ratio (MAC/HC) and ponderal index (PI) had the least correlation with gestation, these were used as independent markers for gestation. Among these three, MAC had the best correlation with birth weight (r = 0.808). A midarm circumference of less than or equal to 8.6 cm and less than or equal to 7.4 cm had the best sensitivity and specificity for identifying neonates with a birth weight of less than or equal to 2500 and less than or equal to 2000 g, respectively. All the anthropometric variable studied can rule out low birth weight with great accuracy (high negative predictive value greater than 90%).

Relationship of maternal serum ferritin with foetal serum ferritin, birth weight and gestation.

Haemoglobin and ferritin estimations employing the micro-ELISA technique were done in 308 random selected mothers in labour and their newborns. The values of haemoglobin and serum ferritin as well as birth weight and gestation of babies born to iron depleted, and mildly and moderately anaemic mothers were no different from those of newborns of non-anaemic women. However, the values of serum ferritin per se in all these newborns were much lower than what are generally reported from the western countries. Babies born to severely anaemic women, on the other hand, showed elevated levels of haemoglobin and serum ferritin, and lower birth weights and gestation. Thus, mild to moderate iron deficiency in the mother does contribute to lower iron reserves in the foetus, if not frank iron depletion, and severe iron deficiency anaemia to lower birth weight and gestation.

Intrauterine growth curves in north Indian babies: weight, length, head circumference and ponderal index.

Intrauterine growth (weight, length, head circumference, Ponderal index) was studied in 2875 consecutive live born babies. Weight, length and head circumference growth curves did not show any significant difference when compared to previous growth curves made 20 years back from this centre. Norms and curves for ponderal index are provided for the Indian babies and were comparable with figures from Western studies. However, the 90th centile values were found to be low between 32-38 weeks of gestation.

Ultrasonic intrauterine growth curves.

Intrauterine growth was studied by serial ultrasonic measurements of biparietal diameter (BPD), femur length (FL) and abdominal circumference (AC) in 241 normal low risk obstetric patients. These measurements were used to construct normal ultrasonic fetal weight and length curve. The data correlate well with the already established, postnatal weight and length curves after 28 weeks of gestation. The fetal ponderal index curve was compared with postnatal ponderal index curves available. Antenatal recognition of fetal weight, length and ponderal index can be used to evaluate pregnancies at risk for altered fetal growth.

Ponderal index as a marker of intrauterine growth.

Anthropometric data obtained from 2925 consecutive live births were used to compute Rohrer's ponderal index (PI). Norms and curves for intrauterine growth in terms of PI were worked out for the first time in our country and were found to be comparable with figures from Western studies. PI was unaffected by sex and showed a linear correlation with gestational age up to 40 wk. PI was also found to be an efficient marker of disproportionate intrauterine growth.

Intra-uterine growth curves for midarm and thigh circumferences.

Use of birth weight as a measure of intrauterine growth is hampered by several logistic problems. Both mid-arm (MAC) and thigh circumferences (TC) have been proved to be efficient alternative measurements. In this study MAC and TC were recorded on 2925 consecutive live births to derive intrauterine growth curves and provide normative data for an indigenous population.