A study of birth weight, placental weight and mortality of twins as compared to singletons.

A study was made of 1655 sets of twins born between 1931 and 1975 in two clinical centres. Compared to singletons, twins were born three weeks earlier, weighed less at birth from 33 weeks to term and had smaller placentae from 21 to 22 weeks to term. The influence on birth weight fo sex was smaller in twins, the influence of parity greater. Because, compared to singletons, lower placental indices were found in twins up to 37 to 38 weeks, the conclusion is drawn that the retardation of growth in twins is to some extent due to the placenta itself. When singletons and twins of the same gestational age were compared, the mortality was found to be similar, somewhat lower in twins up to 37 to 38 weeks and higher afterwards. Monochorial twins were found to be born earlier, weigh less at birth and have a higher mortality than dichorial twins. Placental weights were not different and the conclusion is drawn that the retardation of growth in monochorial twins is to some extent due to the higher incidence of marginal and velamentous insertions of the umbilical cord associated with lower birth weights.     

Perinatal mortality associated with abruptio placenta in singletons and multiples

OBJECTIVE: This study was undertaken to investigate the association among plurality (number of fetuses per pregnancy), abruptio placenta, and perinatal mortality. STUDY DESIGN: A retrospective cohort study on 15,051,872 singletons, 413,619 twins, and 22,585 triplets delivered in the United States between 1995 and 1998 was conducted. We compared the occurrence of perinatal death between pregnancies complicated by abruptio placenta and those without with the use of adjusted odds ratios. The generalized estimating equations framework was applied to adjust for intracluster correlations among multiples. RESULTS: Placental abruption occurred among 93,968 singletons (6.2 per 1000), 5051 twin (12.2 per 1000), and 353 triplet (15.6 per 1000) gestations ( P for trend<.0001). Placental abruption was associated with significant risk of mortality irrespective of the plurality subtype. Perinatal mortality was greatest among singletons (adjusted odds ratio [95% CI]=14.3[13.2-15.4]), followed by twins (4.4[3.9-4.9]) and least among triplets (3.0[2.0-4.6]) ( P for trend<.0001). CONCLUSION: As plurality increases from 1 to 3, the risk of placental abruption rises, whereas the risk of abruptio-associated perinatal mortality declines.     

Independent factors influencing large-for-gestation birth weight in singletons born after in vitro fertilization

Purpose

Higher risk for birth of singletons being large for gestational age (LGA) has been revealed after in vitro fertilization (IVF) frozen–thawed embryo-transfer (FET). This phenomenon is now being investigated, since there is a speculation that these neonates could suffer from underlying epigenetic disturbances. The aim of the study was to expose independent LGA risk factors and to identify those connected to the IVF techniques.

Methods

Altogether, 4508 singleton pregnancies and births were included in the cohort case-matched study. Two hundred eleven singleton pregnancies and births after FET and 916 after fresh embryo transfer (ET) were included into two study groups. The IVF procedures were performed at the University Medical Centre Ljubljana between 2004 and 2011. For each IVF pregnancy, three matched consecutive controls after natural conception were included. Using logistic regression models, we observed LGA connection to maternal parameters (smoking, hypertension, parity, BMI, gestational diabetes, IVF conception, FET, double ET, and ICSI procedure).

Results

Singletons born after FET had a significantly higher risk for being LGA (p = 0.032; OR 1.697; 95 % CI 1.047–2.752). BMI 25–30 was a significant independent risk factor for LGA in the IVF groups (FET p = 0.041, OR 2.460, 95 % CI 1.030–5.857 and fresh ET p = 0.003; OR 2.188, 95 % CI 1.297–3.691). ICSI and double ET had no significant effect on LGA occurrence.

Conclusions

Besides maternal BMI, FET is a significant independent LGA risk factor in IVF patients. Other observed factors (smoking, hypertension, multiparity, GDM, ICSI procedure, or number of embryos transferred) do not influence LGA risk significantly.     

Role of multiple births in very low birth weight and infant mortality

OBJECTIVE: To determine the percentage of very-low-birth-weight (VLBW) infants (<1500 g) and infant deaths attributable to multiple births in the general population and in women aged 35+. STUDY DESIGN: The year 2000 Massachusetts birth certificate database with linked births-deaths was examined. Etiologic fractions (EF) for VLBW and infant mortality attributable to multiples were calculated for the general population and the 35+ age group. The percentages of multiples occurring in the 35+ age group were calculated. Infant deaths due to congenital anomalies and "perinatal conditions" were calculated. RESULTS: There were 81,582 resident births in Massachusetts in 2000. Of them 4.3% were multiples. Of the 1090 VLBW infants, 26.1% (95% CI: 23.5-28.8) were in twins and 7.7% (95% CI: 6.2-9.5) in higher-order multiples, yielding an EF of 30.8% for multiples in VLBW. In the 35+ age group, the multiple birth ratio was 6.6% (95% CI: 6.3-7.0). The EF for multiples and VLBW in this age group was 33.7%. The 35+ age group accounted for 32.4% (95% CI: 30.8-34.0) of twins and 45.5% (95% CI: 39.1-52.0) of higher-order multiples born in 2000. Of the 392 infant deaths, 57 (14.6%; 95% CI: 11.2-18.4) were attributed to congenital anomalies, and 236 (60.2%; 95% CI: 55.2-65.0) to "perinatal conditions." Multiples were responsible for 8 (14%; 95% CI: 6.3-25.8) of deaths due to anomalies, and 73 (30.9%; 95% CI: 25.1-37.3) due to "perinatal conditions." CONCLUSION: Over 30% of VLBW infants, nearly 20% of infant mortality and >30% of infant mortality due to perinatal conditions could be attributed to multiples. Multiple pregnancy is a significant public health problem.     

Outcome of very very low birth weight infants

This review of the literature and selected unpublished data documents normal early outcome in 50 to 81 per cent of tiny infants. Educational outcome described by a few studies is less encouraging, with only 32 to 36 per cent considered normal. Each study investigated the contribution of different perinatal, environmental, or social variables, therefore it is difficult to determine which has most impact on neurodevelopmental outcome.     

An epidemiologic study of very low and very very low birth weight infants

VVLBW infants constitute only 1 per cent of the total births, but account for 60 per cent of the NMR and 40 per cent of the IMR. While improved technology and refinements in care continue to improve survival for VVLBW infants, questions regarding the lower limits of viability must be considered. The medical community can rightly take credit for improvement in outcome of infants with weight and gestations so small that, just a decade ago, they were considered nonviable; however, an excruciatingly slow pace of decline in the prematurity rate is an agonizing fact. Can anything be done to prevent prematurity and avoid its devastating consequences on the family and society? The recent French experience suggests the answer could be "yes." A similar experience also has been reported in the United States. Although VLBW NMR is a major fraction of total IMR, nearly one quarter of first-year deaths occur in infants who are over 2500 gm at birth. That the postneonatal death of normal birth weight infants is only next in magnitude to the neonatal death of VLBW infants further points to the need for developing preventive child health programs encompassing periods before and during the pregnancy, through the immediate peripartum period, and well into infancy and childhood. Neither a woman's pregnancy experience nor the concerns of the health community end with her taking a baby home.     

Nutrition in very very low birth weight infants

The VVLBW infant's limited nutritional reserves, high requirements for normal growth and development, and gastrointestinal immaturity pose a particularly challenging nutritional problem. Given the potential consequences of inadequate or inappropriate nutritional management, we are obligated to make nutrition a high priority in the overall care of VVLBW infants.     

Leminorella sepsis in very low birth weight neonate as cause of neonatal mortality

Leminorella is a member of Enterobacteriaceae family and was known previously as Enteric Group 57. Based upon genetic differences using DNA hybridization, it has three taxa: Leminorella grimontii, Leminorella richardii, and Leminorella sp. strain 3. The third one is similar biochemically to the L. grimontii strains. The generic name has been derived on the name of a French microbiologist, Leon Le Minor. The biochemical properties includes being facultative anaerobes, growth on sheep blood, TSI, and MacConkey agar; hydrogen sulfide producer, l-arabinose fermenter, and tyrosine hydrolyzer; and are negative for d-mannose fermentation, urea, and lipase. They usually infect in adulthood and result in urinary tract infection, surgical site infection, bacteremia, peritonitis, respiratory tract infection, and soft tissue infection. We report the first case of L. grimontii sepsis in a very low birth weight neonate that died because of neonatal sepsis.     

Perinatal risk factors and mode of delivery associated with mortality in very low birth weight infants

Objective: To investigate the association of perinatal risk factors including delivery mode with mortality in very low birthweight (VLBW) in a tertiary hospital setting.

Methods: Medical records of 241 live-born VLBW infants (≤1500?g) were retrospectively reviewed. Details of maternal, obstetrical, perinatal risk factors and their associations with infant mortality were evaluated.

Results: The overall infant mortality rate was 23.2%. Mortality was significantly higher for infants born at ≤27 gestational weeks and with a birthweight of ≤750?g (p?=?0.000 and p?=?0.000, respectively), showing a steep decrease thereafter. On ROC analysis, a cut off of 26.5 weeks was determined for mortality with a sensitivity of 57.1% and a specificity of 90.3% (area under the curve?=?0.792, 95% CI: 0.719–0.866). On multivariate regression analysis, gestational week at birth, birthweight, antenatal steroid treatment and pathologic Doppler ultrasound findings were found as independent risk factors for mortality.

Conclusions: Gestational week at birth, birthweight and antenatal steroid treatment remain the most important perinatal risk factors for infant mortality in VLBW infants. Mode of delivery does not seem to be associated with mortality when adjusted for other perinatal risk factors.     

Perinatal risk factors for pneumothorax and morbidity and mortality in very low birth weight infants

Aim: To determine the perinatal risk factors for pneumothorax in Very-Low-Birth-Weight (VLBW) infants and the associated morbidity and mortality in this population.

Methods: Retrospective analysis of data collected prospectively from a cohort of VLBW neonates assisted in our Unit (2006–2013). We included all consecutive in-born patients with ≤?1500?g, without severe congenital anomalies. Perinatal history, demographics, interventions and clinical outcomes were collected. Associations were evaluated by logistic regression analysis.

Results: During the study period, 803 VLBW infants were assisted in our Unit, of whom 763 were inborn. Ten patients (1.2%) died in delivery room, and 18 (2.2%) with major congenital anomalies were excluded. Finally, 735 (91.5%) neonates were included in the study. Seventeen (2.3%) developed pneumothorax during the first week of life [median (IQR): 2 (1–2) days]. After correcting for GA and other confounders, prolonged rupture of membranes [aOR =1.002 (95% CI 1.000–1.003); p?=?0.040] and surfactant administration [aOR?=?6.281 (95% CI 1.688–23.373); p?=?0.006] were the independent risk factors associated with pneumothorax. Patients with pneumothorax had lower probabilities of survival without major brain damage (MBD): aOR?=?0.283 (95% CI?=?0.095–0.879); p?=?0.029.

Conclusions: Pneumothorax in VLBW seems to be related to perinatal inflammation and surfactant administration, and it is significantly associated with a reduction in the probabilities of survival without MBD.     

Higher glycemic variability in very low birth weight newborns is associated with greater early neonatal mortality

Objective: To determine the association between mean glycemia and its variability with perinatal mortality in preterm newborns hospitalized in an intensive care unit (ICU). Methods: Patients admitted to the ICU within the first 12 hours of life, with birth weight <1500?g, at least three blood glucose measurements/day and lack of insulin treatment were evaluated. Association of mean glycemia and its standard deviation (SD) with death during initial 7 days of life was evaluated. Multivariate logistic regression analysis was performed twice, using continuous glucose concentrations and by means of a quintile-based approach correcting for nonnormal distribution and nonlinear effects. Results: A total of 95 newborns were enrolled. Eleven patients (11.5%) died during the initial 7 days of life, overall mortality equaled 22%. Multivariate analysis showed that 5 minute Apgar score and SD of glucose concentrations were significantly associated with increased mortality in both models. Odds ratios (ORs) equaled 0.44; 95% confidence interval (95% CI) 0.27–0.74 and OR 1.34; 95% CI 1.03–2.03 for the continuous model and 0.50 95% CI 0.34–0.75 and OR 1.82 95% CI 1.07–3.11 for the quintile-based model. In both cases, mean glycemia was removed during the stepwise model-building procedure. Conclusions: Higher glycemic variability may be associated with greater odds of perinatal mortality.     

Outcome of very low birth weight infants with histopathologic chorioamnionitis

OBJECTIVE: To determine neonatal outcome at 7 months of corrected age in very low birth weight (VLBW) infants with placental chorioamnionitis. METHODS: We conducted a cohort study of 287 VLBW infants delivered as a result of preterm premature rupture of membranes (PROM) or preterm labor. Control subjects (n = 123) had placentas with absent umbilical cord inflammation and absent or low-grade membrane inflammation. Case subjects (n = 164) had moderate membrane inflammation or any umbilical cord inflammation. Neonatal and 7-month outcomes were compared. A power analysis showed that 98 total subjects were needed to reject the two-sided null hypothesis with a difference in mean Bayley index scores of at least 8. RESULTS: Infants in the study group had significantly more preterm PROM, antenatal antibiotics, lower birth weight, lower gestational age, longer duration of ruptured membranes, and clinical chorioamnionitis. Intraventricular hemorrhage occurred more commonly in infants with placentas demonstrating chorioamnionitis (relative risk = 1.6, 95% confidence interval 1.1, 2.4, P =.013). One hundred sixty-seven (69%) of the 243 surviving infants had 7-month follow-up. There was no difference between cases and controls in mean Bayley mental developmental index (93 compared with 90, P =.25), psychomotor developmental index (89 compared with 90, P =.68), or in the number of infants that were developmentally delayed. CONCLUSION: Despite a higher frequency of intraventricular hemorrhage, no difference in developmental scores was detected at 7 months of corrected age in VLBW infants with histologic chorioamnionitis.     

Factors influencing survival and morbidity with very low birth weight delivery

Factors influencing survival and morbidity in a group of 214 consecutively delivered very low birth weight infants (500 to 1500 g) are examined. The perinatal mortality was 313 per 1000 births. Of 185 live-born, congenitally normal infants, 133 (72%) were discharged alive. Respiratory distress syndrome was the most common form of significant morbidity, occurring in 114 infants (62%). Intraventricular hemorrhage was diagnosed in 38 (21%) of the infants. Neither survival nor morbidity was influenced by the mode of delivery. The current trend of a liberalized policy of cesarean section for the very low birth weight delivery is questioned.