Low first-trimester hemoglobin and low birth weight, preterm birth and small for gestational age newborns.

OBJECTIVE: To examine the relationship between first-trimester hemoglobin (Hb) concentration and risk of low birth weight (LBW), preterm birth and small for gestational age (SGA). METHODS: Data were obtained from a population-based prenatal care program in China. A total of 88,149 women who delivered during 1995-2000 and had their Hb measured in the first trimester were selected as study subjects. RESULTS: The prevalence of anemia (Hb<110 g/L) was 22.1% in the first trimester. The risk of LBW, preterm birth and SGA was increased steadily with the decrease of first-trimester Hb concentration. After controlling for confounding factors, women with Hb 80-99 g/L had significantly higher risk for LBW (OR=1.44, 95% CI 1.17-1.78), preterm birth (OR=1.34, 95% CI 1.16-1.55) and SGA (OR=1.13, 95% CI 0.98-1.31) than women with Hb 100-119 g/L. No elevated risk was noted for women with Hb> or =120 g/L. CONCLUSION: Low first-trimester Hb concentration increases the risk of LBW, preterm birth and SGA.     

Evaluation of carnitine deficit in very low birth weight preterm newborns small for their gestational age

Objective: To verify whether small-for-gestational-age (SGA) preterm newborns represent a special risk group for carnitine deficiency. Secondary outcome includes assessment of longitudinal differences of total carnitine (TC), free carnitine (FC) and acylcarnitines between SGA and appropriate-for-gestational-age (AGA).

Methods: A retrospective study to evaluate carnitine and acylcarnitines profile on 144 very-low-birth weight newborns (VLBW), classified as AGA (n?=?73) and SGA (n?=?71), was performed by tandem mass spectrometry, during their first 5 weeks of life. Carnitine deficiency was defined as FC <40?µmol/L and FC/TC <0.7.

Results: Carnitine deficiency was observed in the two study groups throughout the monitoring period (maximum FC: 36.05?µmol/L in AGA and 32.24?µmol/L in SGA). FC/TC remains under 0.7 in both with progressive improvement. Unlike expected, a comparatively higher value of TC, FC and total acylcarnitines (tAC) was found in SGA during the first 2 weeks, with significant relevance on day 3–5, especially for tAC (p?<?0.001). The only acylcarnitine with persistently lower value in SGA is C5 (p?<?0.05 in first 2 weeks).

Conclusions: A carnitine deficiency was demonstrated in all VLBW. Although birth weight restriction has been suggested as a risk factor for impaired carnitine status, in our study, SGA was not related with higher carnitine deficiency.     

Development of renal function in low and extremely low birth weight infants: correlation with gestational and postnatal age

The postnatal development of renal function was compared in 29 infants with a gestation age (GA) of 26-30 weeks mean 28.5 680-1,450 g means 1080 g and in 31 infants with a gestation age of 31-33-weeks, means 31.5, 950-2000 g means 1580 g. Observation were made during the 1st, 5th and 10th day. From 1st to 10th day the creatinine clearance increased but it was significantly lower in GA 26-30 that in GA 31-33. During the first 10 days of life diuresis was lower in GA 26-30 that in GA 31-33 but thereafter was the same in both groups. Urinary sodium excretion was high at 1st and 5th day in both groups and decreased with increasing postnatal age. Na excretion was slightly higher in GA 26-30 that in GA 31-33 at 1st and 5th day but not at 10th day. UK/UNa was below 1 in both groups during the 1st, 5th day and increased with postnatal age. FeNa% was high in both groups but in GA 26-30 was significantly hither then in GA 31-33. We conclude that the postnatal development of renal function is retarded in all preterm infants and is slightly slower in infants with a GA below 31 weeks than in infants with GA 31-33 weeks.     

The very low birth weight and very low gestational age neonates--survival, prognosis and perspectives

The advances in perinatal medicine during the last decades lead to a reduction in neonatal mortality rates in risk newborns and a gradual lowering of the gestational age when survival is possible to 22 weeks of gestation. In the present survey we are making a review of the studies about the survival and the prognosis in neonates with very low birth weight and gestational age (VLBW, VLGA). Infants weighting more than 1000 g and with gestational age above 28 g.w. are with a good prognosis: low neonatal mortality and morbidity rates. In newborns with gestational age between 26 and 28 g.w. the neonatal mortality rates are relatively low, however the trend of further lowering has not changed during the last 15 years; morbidity rates varies between different centers and are relatively high. The greatest medical, social and ethical dilemmas represent the newborns with gestational age less than 25 g.w. In this group with an overall high neonatal mortality (with big variations between different centers), there is a significant high morbidity rate among survived babies. These are the infants at the border of perinatal viability, the "grey zone" of the neonatology, where further discussions are going on about the activity of the obstetric management, the intensity and the amount of neonatal resuscitation.     

Association between congenital toxoplasmosis and preterm birth, low birthweight and small for gestational age birth

OBJECTIVE: To determine the association between congenital toxoplasmosis and preterm birth, low birthweight and small for gestational age birth. DESIGN: Multicentre prospective cohort study. SETTING: Ten European centres offering prenatal screening for toxoplasmosis. POPULATION: Deliveries after 23 weeks of gestation in 386 women with singleton pregnancies who seroconverted to toxoplasma infection before 20 weeks of gestation. Deliveries after 36 weeks in 234 women who seroconverted at 20 weeks or later, and tested positive before 37 weeks. METHODS: Comparison of infected and uninfected births, adjusted for parity and country of birth. MAIN OUTCOME MEASURES: Differences in gestational age at birth, birthweight and birthweight centile. RESULTS: Infected babies were born or delivered earlier than uninfected babies: the mean difference for seroconverters before 20 weeks was -5.4 days (95% CI: -1.4, -9.4), and at 20 weeks or more, -2.6 days (95% CI: -0.5, -4.7). Congenital infection was associated with an increased risk of preterm delivery when seroconversion occurred before 20 weeks (OR 4.71; 95% CI: 2.03, 10.9). No significant differences were detected for birthweight or birthweight centile. CONCLUSION: Babies with congenital toxoplasmosis were born earlier than uninfected babies but the mechanism leading to shorter length of gestation is unknown. Congenital infection could precipitate early delivery or prompt caesarean section or induction of delivery. We found no evidence for a significant association between congenital toxoplasmosis and reduced birthweight or small for gestational age birth.     

The early use of minimal enteral nutrition in extremely low birth weight newborns.

OBJECTIVE: To gather information regarding the efficacy of early minimal enteral nutrition on overall feeding tolerance in extremely low birth weight infants. STUDY DESIGN: Prospective randomized controlled trial comparing the early use of minimal enteral nutrition in extremely low birth weight infants from day 2 to day 7 vs control infants. On day 8, feeding volume in both groups were advanced by 10 ml kg(-1) day(-1) until full enteral feedings were reached. Time to full feeds, number of intolerance episodes, anthropometric measurements, peak total bilirubin levels, incidence of necrotizing enterocolitis and incidence of sepsis were compared between the two groups with t-test and chi (2) test. RESULT: Eighty-four infants were enrolled in the study but only 61 infants completed the feeding protocol. No statistically significant differences were found between the groups with regards to growth patterns, feeding tolerance, mortality, length of hospital stay and incidence of sepsis and necrotizing enterocolitis. CONCLUSION: Early minimal enteral nutrition use in extremely low birth weight infants did not improve feeding tolerance.     

Association between early postnatal weight loss and death or BPD in small and appropriate for gestational age extremely low-birth-weight infants.

OBJECTIVE: To examine the association between weight loss during the first 10 days of life and the incidence of death or bronchopulmonary dysplasia (BPD) in small for gestational age (SGA) and appropriate for gestational age (AGA) extremely low-birth-weight infants. DESIGN/METHODS: This is a retrospective analysis of a cohort of ELBW (birth weight <1000 g) infants from the NICHD Neonatal Research Network's database. The cohort consisted of 9461 ELBW infants with gestational age of 24-29 weeks, admitted to Network's participating centers during calendar years 1994-2002 and surviving at least 72 h after birth. The cohort was divided into two groups, 1248 SGA (with birth weight below 10th percentile for gestational age) and 8213 AGA (with birth weight between 10th and 90th percentile) infants. We identified infants with or without weight loss during the first 10 days of life, which we termed as 'early postnatal weight loss' (EPWL). Univariate analyses were used to predict whether EPWL was related to the primary outcome, death or BPD, within each birth weight/gestation category (SGA or AGA). BPD and death were also analyzed separately in relation to EPWL. Logistic regression analysis was done to evaluate the risk of death or BPD in SGA and AGA groups, controlling for maternal and neonatal demographic and clinical factors found to be significant by univariate analysis. RESULTS: SGA ELBW infants had a lower prevalence of EPWL as compared with AGA ELBW infants (81.2 vs 93.7%, respectively, P<0.001). In AGA infants, univariate analysis showed that death or BPD rate was lower in the group of infants with EPWL compared with infants without EPWL (53.4 vs 74.3%, respectively, P<0.001). The BPD (47.2 vs 64%, P<0.001) and death (13.8 vs 32.9%, P<0.001) rate were similarly lower in the EPWL group. The risk-adjusted odds ratios (ORs) showed that EPWL was associated with lower rate of death or BPD (OR 0.47, 95% CI: 0.37-0.60). In SGA infants, on univariate analysis, a similar association between EPWL and outcomes was seen as shown in AGA infants: death or BPD (55.9 vs 75.2%, P<0.001), BPD rate (48.3 vs 62.1%, P=0.002) and rate death (19 vs 40.8%, P<0.001) for those with or without EPWL, respectively. Multiple logistic regression showed that as in AGA ELBW infants, EPWL was associated with lower risk for death or BPD (OR 0.60, 95% CI: 0.41-0.89) among SGA infants. CONCLUSIONS: SGA infants experienced less EPWL when compared with their AGA counterparts. EPWL was associated with a lower risk of death or BPD in both ELBW AGA and SGA infants. These data suggest that clinicians who consider the association between EPWL and risk of death or BPD should do so independent of gestation/birth weight status.     

Inaccuracy of Dubowitz gestational age in low birth weight infants

The Dubowitz gestational age was compared to the obstetric clinical age of 119 predominantly black mother-infant pairs for whom certain clinical criteria were met. Forty-five hypertensive and 74 nonhypertensive gestations with infant birth weight less than 2500 g were evaluated. Overall the clinical age was 33.6 +/- 4.5 weeks versus 34.7 +/- 4.3 weeks by Dubowitz age (P = NS). The Dubowitz age differed from clinical age by more than 2 weeks in 33.6% (40/119). Of gestations under 33 weeks (clinical age) (N = 45) the clinical age was 30.1 +/- 2.4 weeks as compared to the Dubowitz age of 32.2 +/- 2.7 weeks (P less than .01). Fifty-one percent (23/45) of Dubowitz ages were more than two weeks discordant with the clinical age. The Dubowitz assessment of gestational age may be unacceptably inaccurate in the determination of gestational age in low birth weight infants, particularly in those whose gestational age is less than 33 weeks. The findings suggest that studies in which conclusions were based on the Dubowitz age assessment may need reevaluation.     

Analysis of amino acids and acyl carnitine profiles in low birth weight,preterm, and small for gestational age neonates

Objective: To analyze the amino acids (AA) and acyl carnitine (AC) profiles in dry blood spot (DBS) specimens of low birth weight (LBW), preterm birth (PTB), and small for gestational age (SGA), and to compare the concentration difference of AA and AC with those without above.

Methods: This is a retrospectively study. Eight thousand nine hundred and seventy-nine uncomplicated pregnant newborns were enrolled into the study. DBS were collected on the third day of life, and concentrations of 11 types of AA, free carnitine and 30 types of AC were detected by using high-performance liquid chromatography tandem mass spectrometry (HPLC–MS). Shapiro–Wilk test and Kruskal–Wallis rank test were applied in statistical analysis.

Results: Concentrations of most AA and AC in infants born in SGA were significantly higher than those in non-SGA group, while lower in LBW and PTB groups than those in non-LBW and non-PTB groups (p?Conclusions: The difference of concentration of AA and AC in the subgroups suggested there may be a dysutilization of AA and AC in SGA, but an inborn insufficient of AA and AC in LBW and PTB neonates.     

Survival of infants with low birth weight and early gestational age, 1979 to 1981

A chart for displaying neonatal survival data regarding low birth weight and early gestational age is presented. Survival data at two institutions for infants with low birth weight and early gestational age are compared. This format is useful for student and resident teaching, for counseling parents-to-be about potential outcomes, for consulting with out-of-hospital physicians who request advice about maternal-fetal transport, and most important, for helping to make the crucial decisions necessary during the management of labor and delivery of infants with low birth weight and early gestational age.     

The association between second trimester estimated fetal weight and small for gestational age at birth

Objective: To analyze diagnostic accuracy of second trimester ultrasound fetal growth parameters as predictors of small for gestational age (SGA) birth weight.

Methods: We reviewed the fetal biometry from 714 consecutive patients with second trimester ultrasounds. The estimated fetal weight (EFW) and abdominal circumference (AC) percentiles were tested as predictors of SGA at birth (<10‰).

Results: 87 (12.2%) patients had an SGA baby. Patients with a second trimester EFW?≤25‰ were significantly more likely to have SGA at birth (24.2% versus 10.3%, p?<?0.001). Similar results were seen for women with second trimester AC?≤25‰ (likelihood of SGA 21.9% versus 11.2%, p?=?0.013). A second trimester EFW?≤25‰ was a better predictor of SGA at birth than a second trimester EFW?≤?10‰ (Positive likelihood ratio 2.30 versus 2.09). In the second trimester, only 9 (1.3%) patients had an EFW 0–10‰, only 43 (6%) patients had an EFW 11–20‰, and only 46 (6.4%) patients had an EFW 91–99‰. Each other EFW centile had more than 10% of the patients.

Conclusions: The incidence of second trimester EFW or AC?≤10‰ is less common than expected from standard tables. An EFW?≤25‰ and an AC?≤25‰ should be considered the second trimester marker for risk of SGA at birth. However, due to the low likelihood ratio of, it is not clear if second trimester ultrasound should be used as a predictor of SGA at birth.     

The influence of previous low birth weight on birth weight, gestational age, and anthropometric measurements in the current pregnancy.

The effect of a previous low birth weight birth (less than 2750 g) was examined using a series of regression analyses. Effects on birth weight were partitioned into those associated with preterm delivery (128 g) and term delivery (178 g). Among term births, a mean difference of 107 g was associated with a previous birth of less than 2750 g, even after controlling for other risk factors including smoking, drug and alcohol use, maternal race, size, and hypertension. The pattern of measurements seen after a previous birth of less than 2750 g included significantly smaller head, chest, abdomen, arm, and thigh circumferences, but an insignificant impact on skinfold thicknesses and no significant effect on length measurements.     

Plasma adrenomedullin levels in pregnancies with appropriate for gestational age and small for gestational age infants.

AIMS: To evaluate whether maternal and fetal plasma adrenomedullin levels in pregnancies with small for gestational age (SGA) infants are different from those in pregnancies with appropriate for gestational age (AGA) infants. METHODS: Maternal and fetal circulating adrenomedullin levels were compared between 62 pregnancies with AGA (43 delivered vaginally and 19 delivered by elective cesarean section) and 28 pregnancies with SGA (20 delivered vaginally and 8 delivered by elective cesarean section) at birth. Plasma adrenomedullin levels were measured from maternal and cord venous blood samples using a radioimmunoassay. Umbilical artery blood pH was also measured. RESULTS: There were no significant differences for maternal total adrenomedullin levels, mature adrenomedullin levels, and its ratio among the groups. There were also no significant differences for fetal total adrenomedullin levels, mature adrenomedullin levels, and its ratio among the groups. In the AGA group delivered vaginally, fetal mature/total adrenomedullin ratio (mean +/- standard error, 16.6 +/- 0.7%) was significantly higher than the maternal ratio (13.8 +/- 0.6%) (p < 0.05). In the SGA group delivered vaginally, fetal mature/total adrenomedullin ratio (18.5 +/- 1.0%) was also significantly higher than the maternal ratio (14.5 +/- 0.6%) (p < 0.05). There was no significant difference in umbilical artery blood pH among the groups. CONCLUSIONS: These results suggest that maternal and fetal plasma circulating adrenomedullin levels may play a role in maternal and fetal cardiovascular adaptation during delivery in pregnancies with both AGA and SGA infants.