Extremely growth-retarded infants: is there a viability centile?

[Medical termination of pregnancy for isolated intrauterine growth retardation beyond 24 weeks and more than 450g]

INTRODUCTION

Fetal growth restriction (FGR) is an obstetric complication responsible for increased perinatal morbidity and mortality. In some severe and early FGR situations, termination of pregnancy (TOP) may be considered. The main objective of our study was to describe the population of fetuses for whom a TOP was performed for isolated FGR beyond 24 days' gestation and for a birth weight>450g and to analyze the immediate outcome, at 2 and 5 years, of term- and weight-matched neonates born in a context of severe FGR after 24 weeks' gestation and over 450g.

MATERIAL AND METHODS

We conducted an observational, descriptive, retrospective, uni-centric study between 2008 and 2018. The primary endpoint was survival at maternity discharge, 2 years and 5 years in these children. Secondary endpoints were assessment of immediate and longer-term postnatal morbidity. Twenty-five patients (36%) were selected for the study with a fetus weight>450g and term>24 weeks. Each fetus with an TOP was matched (on gestational age and weight) with two live-born children from the perinatal network cohort to assess immediate discharge outcome, and then at 2 and 5 years.

RESULTS

The mortality rate was 24%. In neonatal management, for 67% (n=17) of the newborns the evolution was complicated by death or at least two sequelae (bronchopulmonary dysplasia, hyaline membrane disease stage≥2, intraventricular of grade 3 and 4, ulcerative colitis requiring surgery, retinopathy of prematurity stage 2 and more) at discharge. In 32% (n=8) of cases, there was at least one sequela at discharge. Regardless of gestational age at birth, development at 2 years was normal for 48% (n=11/23) of them and abnormal for 22% (n=5) and development at 5 years was normal for 56% (n=9/16) of them and abnormal for 19% (n=5).

CONCLUSION

An ultrasound evaluation in a reference center as well as additional information by the obstetrician and neonatologist ensures the most appropriate informed involvement of the couple in the medical decisions before and after birth.

Outcomes in extremely low birth weight (≤500 g) preterm infants: A Western Australian experience

BACKGROUND AND AIM

Extremely preterm (EP) infant survival has significantly improved with advanced neonatal care; however outcomes of infants born with birth weight (BW) ≤500 g remain poor. We aimed to review outcomes of this cohort in our institution.

METHODS

Retrospective study of all inborn preterm infants born at ≥22 weeks gestational age (GA) and weighing ≤500 g between January 2001-December 2017. Outcomes included short-term morbidity, mortality, neurodevelopmental impairment and growth up to five years of age.

RESULTS

Of a total 438 eligible infants, 92 livebirths were admitted to intensive care [median (range) GA: 24 (22-30) weeks; median (IQR) BW: 427.5 (380-499) grams]. Majority [78/92 (84.7%)] were small for gestational age (SGA). In 50% of non-survivors, median (IQR) age of death was 3.5 (1-17.5) days with no late deaths. Medical morbidities were common. Follow-up, including standardised cognitive assessments, was available for 41/46 (89%) infants. At a median age of 5.06 years, 17/41 (41.5%) had moderate-severe disability; non-statistically higher in SGA compared to appropriate for gestational age/AGA (48.6% vs. 33.3%) group. Cerebral palsy (4/41; 10%), deafness needing amplification (1/41; 2.4%) were noted. Weight (32/41, 78%) and height (27/41, 66%) of most children remained at >2 SD below normal.

CONCLUSIONS

In a cohort of preterm infants weighing ≤500 g at birth, 50% survived after admission to intensive care. Medical morbidities were common and 54% were free from moderate to severe disability at five years. SGA infants had higher rates (48.6%) of moderate to severe disability. Ongoing suboptimal growth in childhood is common.

Outcomes of infants with a birthweight less than or equal to 500 g in Northern England: 15 years experience

AIM

We aimed to evaluate mortality and short-term neonatal morbidity of babies born ≤500 g cared for in the Northern Neonatal Network over a 15-year period.

METHOD

Using regional databases, we identified all live-born babies ≥22 weeks gestation and ≤500 g, in North East England and North Cumbria from 1998 to 2012. We quantified major neonatal morbidities and survival to one year.

RESULTS

We identified 104 live-born babies ≥22 weeks gestation and ≤500 g (birth prevalence 0.22/1000), of which 49 were admitted for intensive care. Overall one-year survival was 11%, but survival for those receiving intensive care was 22%. There was significant short-term neonatal morbidity in survivors, in particular retinopathy of prematurity and chronic lung disease.

CONCLUSION

Survival of babies born weighing ≤500 g in this cohort remains poor despite advances in neonatal care, with considerable short-term neonatal morbidity in survivors. This could be due to a combination of attitudes and a rather conservative approach towards resuscitation and intensive care, and the intrinsic nature of these tiny babies.

Comparing very low birth weight versus very low gestation cohort methods for outcome analysis of high risk preterm infants

Background

Compared to very low gestational age (<32 weeks, VLGA) cohorts, very low birth weight (<1500 g; VLBW) cohorts are more prone to selection bias toward small-for-gestational age (SGA) infants, which may impact upon the validity of data for benchmarking purposes.

Method

Data from all VLGA or VLBW infants admitted in the 3 Networks between 2008 and 2011 were used. Two-thirds of each network cohort was randomly selected to develop prediction models for mortality and composite adverse outcome (CAO: mortality or cerebral injuries, chronic lung disease, severe retinopathy or necrotizing enterocolitis) and the remaining for internal validation. Areas under the ROC curves (AUC) of the models were compared.

Results

VLBW cohort (24,335 infants) had twice more SGA infants (20.4% vs. 9.3%) than the VLGA cohort (29,180 infants) and had a higher rate of CAO (36.5% vs. 32.6%). The two models had equal prediction power for mortality and CAO (AUC 0.83), and similarly for all other cross-cohort validations (AUC 0.81–0.85). Neither model performed well for the extremes of birth weight for gestation (<1500 g and ≥32 weeks, AUC 0.50–0.65; ≥1500 g and <32 weeks, AUC 0.60–0.62).

Conclusion

There was no difference in prediction power for adverse outcome between cohorting VLGA or VLBW despite substantial bias in SGA population. Either cohorting practises are suitable for international benchmarking.

Electronic supplementary material

The online version of this article (doi:10.1186/s12887-017-0921-x) contains supplementary material, which is available to authorized users.

The use of angiogenic biomarkers in maternal blood to identify which SGA fetuses will require a preterm delivery and mothers who will develop pre-eclampsia

OBJECTIVE

To determine (1) whether maternal plasma concentrations of angiogenic and anti-angiogenic factors can predict which mothers diagnosed with "suspected small for gestational age fetuses (sSGA)" will develop pre-eclampsia (PE) or require an indicated early preterm delivery (≤ 34 weeks of gestation); and (2) whether risk assessment performance is improved using these proteins in addition to clinical factors and Doppler parameters.

METHODS

This prospective cohort study included women with singleton pregnancies diagnosed with sSGA (estimated fetal weight <10th percentile) between 24 and 34 weeks of gestation (n = 314). Plasma concentrations of soluble vascular endothelial growth factor receptor-1 (sVEGFR-1), soluble endoglin (sEng) and placental growth factor (PlGF) were determined in maternal blood obtained at the time of diagnosis. Doppler velocimetry of the umbilical (Umb) and uterine (UT) arteries was performed. The outcomes were (1) subsequent development of PE; and (2) indicated preterm delivery at ≤ 34 weeks of gestation (excluding deliveries as a result of spontaneous preterm labor, preterm pre-labor rupture of membranes or chorioamnionitis).

RESULTS

(1) The prevalence of PE and indicated preterm delivery was 9.2% (n = 29/314) and 7.3% (n = 23/314), respectively; (2) the area under the receiver operating characteristic curve (AUC) for the identification of patients who developed PE and/or required indicated preterm delivery was greater than 80% for the UT artery pulsatility index (PI) z-score and each biochemical marker (including their ratios) except sVEGFR-1 MoM; (3) using cutoffs at a false positive rate of 15%, women with abnormal plasma concentrations of angiogenic/anti-angiogenic factors were 7-13 times more likely to develop PE, and 12-22 times more likely to require preterm delivery than those with normal plasma MoM concentrations of these factors; (4) sEng, PlGF, PIGF/sEng and PIGF/sVEGFR-1 ratios MoM, each contributed significant information about the risk of PE beyond that provided by clinical factors and/or Doppler parameters: women who had low MoM values for these biomarkers were at 5-9 times greater risk of developing PE than women who had normal values, adjusting for clinical factors and Doppler parameters (adjusted odds ratio for PlGF: 9.1, PlGF/sEng: 5.6); (5) the concentrations of sVEGFR-1 and PlGF/sVEGFR-1 ratio MoM, each contributed significant information about the risk of indicated preterm delivery beyond that provided by clinical factors and/or Doppler parameters: women who had abnormal values were at 8-9 times greater risk for indicated preterm delivery, adjusting for clinical factors and Doppler parameters; and (6) for a two-stage risk assessment (Umb artery Doppler followed by Ut artery Doppler plus biochemical markers), among women who had normal Umb artery Doppler velocimetry (n = 279), 21 (7.5%) developed PE and 11 (52%) of these women were identified by an abnormal UT artery Doppler mean PI z-score (>2SD): a combination of PlGF/sEng ratio MoM concentration and abnormal UT artery Doppler velocimetry increased the sensitivity of abnormal UT artery Doppler velocimetry to 76% (16/21) at a fixed false-positive rate of 10% (p = 0.06).

CONCLUSION

Angiogenic and anti-angiogenic factors measured in maternal blood between 24 and 34 weeks of gestation can identify the majority of mothers diagnosed with "suspected SGA" who subsequently developed PE or those who later required preterm delivery ≤ 34 weeks of gestation. Moreover, incorporation of these biochemical markers significantly improves risk assessment performance for these outcomes beyond that of clinical factors and uterine and umbilical artery Doppler velocimetry.

Towards reducing variations in infant mortality and morbidity: a population-based approach

Background

Our aims were (1) to improve understanding of regional variation in early-life mortality rates and the UK’s poor performance in international comparisons; and (2) to identify the extent to which late and moderately preterm (LMPT) birth contributes to early childhood mortality and morbidity.

Objective

To undertake a programme of linked population-based research studies to work towards reducing variations in infant mortality and morbidity rates.

Design

Two interlinked streams: (1) a detailed analysis of national and regional data sets and (2) establishment of cohorts of LMPT babies and term-born control babies.

Setting

Cohorts were drawn from the geographically defined areas of Leicestershire and Nottinghamshire, and analyses were carried out at the University of Leicester.

Data sources

For stream 1, national data were obtained from four sources: the Office for National Statistics, NHS Numbers for Babies, Centre for Maternal and Child Enquiries and East Midlands and South Yorkshire Congenital Anomalies Register. For stream 2, prospective data were collected for 1130 LMPT babies and 1255 term-born control babies.

Main outcome measures

Detailed analysis of stillbirth and early childhood mortality rates with a particular focus on factors leading to biased or unfair comparison; review of clinical, health economic and developmental outcomes over the first 2 years of life for LMPT and term-born babies.

Results

The deprivation gap in neonatal mortality has widened over time, despite government efforts to reduce it. Stillbirth rates are twice as high in the most deprived as in the least deprived decile. Approximately 70% of all infant deaths are the result of either preterm birth or a major congenital abnormality, and these are heavily influenced by mothers’ exposure to deprivation. Births at < 24 weeks’ gestation constitute only 1% of all births, but account for 20% of infant mortality. Classification of birth status for these babies varies widely across England. Risk of LMPT birth is greatest in the most deprived groups within society. Compared with term-born peers, LMPT babies are at an increased risk of neonatal morbidity, neonatal unit admission and poorer long-term health and developmental outcomes. Cognitive and socioemotional development problems confer the greatest long-term burden, with the risk being amplified by socioeconomic factors. During the first 24 months of life each child born LMPT generates approximately £3500 of additional health and societal costs.

Conclusions

Health professionals should be cautious in reviewing unadjusted early-life mortality rates, particularly when these relate to individual trusts. When more sophisticated analysis is not possible, babies of < 24 weeks’ gestation should be excluded. Neonatal services should review the care they offer to babies born LMPT to ensure that it is appropriate to their needs. The risk of adverse outcome is low in LMPT children. However, the risk appears higher for some types of antenatal problems and when the mother is from a deprived background.

Future work

Future work could include studies to improve our understanding of how deprivation increases the risk of mortality and morbidity in early life and investigation of longer-term outcomes and interventions in at-risk LMPT infants to improve future attainment.

Funding

The National Institute for Health Research Programme Grants for Applied Research programme.

An Algorithm for Predicting Neonatal Mortality in Threatened Very Preterm Birth

OBJECTIVE

To develop a prediction model for neonatal mortality using information readily available in the antenatal period.

METHODS

A multiple logistic regression model of a complete population-based geographically defined cohort of very preterm infants of 23+0 to 30+6 weeks' gestation was used to identify antenatal factors which were predictive of mortality in this population. Infants lt; 23 weeks and those with major anomalies were excluded.

RESULTS

Between 1996 and 2012, 1240 live born infants lt; 31 weeks' gestation were born to women residing in Nova Scotia. Decreasing gestational age strongly predicted an increased mortality rate. Other factors significantly contributing to increased mortality included classification as small for gestational age, oligohydramnios, maternal psychiatric disorders, antenatal antibiotic therapy, and monochorionic twins. Reduced neonatal mortality was associated with antenatal use of antihypertensive agents and use of corticosteroids of any duration of therapy given at least 24 hours before delivery. An algorithm was developed to estimate the risk of mortality without the need for a calculator.

CONCLUSION

Prediction of the probability of neonatal mortality is influenced by maternal and fetal factors. An algorithm to estimate the risk of mortality facilitates counselling and informs shared decision making regarding obstetric management.

Size at birth by gestational age and hospital mortality in very preterm infants: results of the area-based ACTION project

BACKGROUND

Size at birth is an important predictor of neonatal outcomes, but there are inconsistencies on the definitions and optimal cut-offs.

AIMS

The aim of this study is to compute birth size percentiles for Italian very preterm singleton infants and assess relationship with hospital mortality.

STUDY DESIGN

Prospective area-based cohort study.

SUBJECTS

All singleton Italian infants with gestational age 22-31 weeks admitted to neonatal care in 6 Italian regions (Friuli Venezia-Giulia, Lombardia, Marche, Tuscany, Lazio and Calabria) (n. 1605).

OUTCOME MEASURE

Hospital mortality.

METHODS

Anthropometric reference charts were derived, separately for males and females, using the lambda (λ) mu (μ) and sigma (σ) method (LMS). Logistic regression analysis was used to estimate mortality rates by gestational age and birth weight centile class, adjusting for sex, congenital anomalies and region.

RESULTS

At any gestational age, mortality decreased as birth weight centile increased, with lowest values observed between the 50th and the 89th centiles interval. Using the 75th-89th centile class as reference, adjusted mortality odds ratios were 7.94 (95% CI 4.18-15.08) below 10th centile; 3.04 (95% CI 1.63-5.65) between the 10th and 24th; 1.96 (95% CI 1.07-3.62) between the 25th and the 49th; 1.25 (95% CI 0.68-2.30) between the 50(h) and the 74th; and 2.07 (95% CI 1.01-4.25) at the 90th and above.

CONCLUSIONS

Compared to the reference, we found significantly increasing adjusted risk of death up to the 49th centile, challenging the usual 10th centile criterion as risk indicator. Continuous measures such as the birthweight z-score may be more appropriate to explore the relationship between growth retardation and adverse perinatal outcomes.

Low birth weight is a risk factor for severe retinopathy of prematurity depending on gestational age

Objective

To evaluate the impact of low birth weight as a risk factor for retinopathy of prematurity (ROP) that will require treatment in correlation with gestational age at birth (GA).

Study design

In total, 2941 infants born <32 weeks GA were eligible from five cohorts of preterm infants previously collected for analysis in WINROP (Weight IGF-I Neonatal ROP) from the following locations: Sweden (EXPRESS) (n = 426), North America (n = 1772), Boston (n = 338), Lund (n = 52), and Gothenburg (n = 353). Data regarding GA at birth, birth weight (BW), gender, and need for ROP treatment were retrieved. Birth weight standard deviation scores (BWSDS) were calculated with Swedish as well as Canadian reference models. Small for gestational age (SGA) was defined as BWSDS less than −2.0 SDS using the Swedish reference and as BW below the 10^th percentile using the Canadian reference charts.

Results

Univariate analysis showed that low GA (p<0.001), low BW (p<0.001), male gender (p<0.05), low BWSDS_Canada (p<0.001), and SGA_Canada (p<0.01) were risk factors for ROP that will require treatment. In multivariable logistic regression analysis, low GA (p<0.0001), male gender (p<0.01 and p<0.05), and an interaction term of BWSDS*GA group (p<0.001), regardless of reference chart, were risk factors. Low BWSDS was less important as a risk factor in infants born at GA <26 weeks compared with infants born at GA ≥26 weeks calculated with both reference charts (BWSDS_Sweden, OR = 0.80 vs 0.56; and BWSDS_Canada, OR = 0.72 vs 0.41).

Conclusions

Low BWSDS as a risk factor for vision-threatening ROP is dependent on the infant's degree of immaturity. In more mature infants (GA ≥26 weeks), low BWSDS becomes a major risk factor for developing ROP that will require treatment. These results persist even when calculating BW deficit with different well-established approaches.

Long-term outcome for the tiniest or most immature babies: survival rates

This article focuses on the survival rates of the most immature babies considered viable from around the world. It discusses the various factors in terms of definition, inclusion criteria and policy which can result in marked differences in the apparent rates of delivery (all births), live birth, admission to neonatal intensive care and ultimately survival seen between otherwise similar countries, different regions of the same country, and even adjacent hospitals. Such variation in approach can result in major differences in reported survival and consequentially have large effects on apparent rates of adverse long-term outcome.

Cord blood biomarkers of vascular endothelial growth (VEGF and sFlt-1) and postnatal growth: a preterm birth cohort study

BACKGROUND

Preterm infants are at risk for postnatal growth failure (PGF). Identification of biomarkers that are associated with neonatal growth may help reduce PGF and associated long-term morbidity.

OBJECTIVE

To investigate the associations between cord blood vascular endothelial growth factor (VEGF) and its soluble receptor (sFlt-1) with birth weight (BW) and postnatal growth in premature infants.

STUDY DESIGN AND METHODS

From an ongoing birth cohort, 123 premature infants from 23 to 36 weeks gestational age (GA) were studied. Cord blood plasma VEGF and sFlt-1 were measured via enzyme-linked immunoassay. Growth parameters and nutritional information were evaluated. Multivariate logistic regression models were constructed to evaluate the associations of VEGF and sFlt-1 on PGF, defined as weight <10th percentile at 36 weeks corrected age or discharge.

RESULTS

VEGF was positively correlated, and sFlt-1 was negatively correlated with BW and BW-for-GA percentiles. Higher cord blood VEGF levels were associated with reduced risk of PGF (OR=0.7; 95% CI=0.5-0.9), while higher sFlt-1 levels appeared to increase the risk of PGF (OR=1.6; 95% CI=1.1-2.4). The above biomarker associations were attenuated after adjustment for maternal preeclampsia, fetal growth restriction and related neonatal characteristics, and when taking into account placental vascular pathologies. Longitudinal growth patterns by mean weight and length percentiles were consistently lower among infants with low VEGF/sFlt-1 ratios.

CONCLUSIONS

Our data support that intrauterine regulation of angiogenesis is an important mechanism of fetal and postnatal growth. Cord blood VEGF and sFlt-1 are useful in elucidating how intrauterine processes may have long-standing effects on developing premature infants.

Outcomes of small for gestational age infants born at <27 weeks' gestation

OBJECTIVE

To determine whether small for gestational age (SGA) infants born at <27 weeks gestational age (GA) are at increased risk for mortality, morbidity, and growth and neurodevelopmental impairment at 18-22 months corrected age.

STUDY DESIGN

This was a retrospective cohort study from National Institute of Child Health and Human Development Neonatal Research Network's Generic Database and Follow-Up Studies. Infants born at <27 weeks GA between January 2006 and July 2008 were included. SGA was defined as birth weight <10th percentile for GA based on Olsen growth curves. Infants with birth weight ≥ 10th percentile for GA were classified as non-SGA. Maternal and infant characteristics, neonatal outcomes, and neurodevelopmental data were compared in SGA and non-SGA infants. Neurodevelopmental impairment was defined as any of the following: cognitive score <70 on the Bayley Scales of Infant Development III, moderate or severe cerebral palsy, bilateral hearing loss (with and without amplification), or blindness (bilateral vision <20/200). Logistic regression analysis was applied to evaluate the associations between SGA status and death or neurodevelopmental impairment.

RESULTS

The SGA group comprised 385 infants; the non-SGA group, 2586 infants. Compared with mothers of non-SGA infants, mothers of SGA infants were more likely to have a high school education, prenatal care, cesarean delivery, pregnancy-induced hypertension, and antenatal corticosteroid exposure. Compared with non-SGA infants, SGA infants had higher mortality and were more likely to have postnatal growth failure, prolonged mechanical ventilation, and postnatal steroid use. SGA status was associated with increased risk of death or neurodevelopmental impairment (OR, 3.91; 95% CI, 2.91-5.25; P < .001).

CONCLUSION

SGA status in infants born at <27 weeks GA is associated with an increased likelihood of postnatal steroid use, mortality, growth failure, and neurodevelopmental impairment at 18-22 months corrected age.

Comparing regional infant death rates: the influence of preterm births <24 weeks of gestation

OBJECTIVE

To investigate regional variation in the registration of preterm births <24 weeks of gestation and the impact on infant death rates for English Primary Care Trusts (PCTs).

DESIGN

Cohort study.

SETTING

England.

PARTICIPANTS

All registered births (1 January 2005-31 December 2008) by gestational age and PCT (147 trusts) linked to infant deaths (up to 1 year of life). Late-fetal deaths at 22 and 23 weeks gestation (1 January 2005-31 December 2006).

MAIN OUTCOME MEASURES

Extremely preterm (<24 weeks) birth rate per 1000 live births and percentage of births registered as live born by PCT. Infant death rate and rank of mortality for (1) all live births and (2) live births over 24 weeks gestation by PCT.

RESULTS

Wide between-PCT variation existed in extremely preterm birth (<24 weeks) rates (per 1000 births) (90% central range (0.31, 1.91)) and percentages of births <24 weeks of gestation registered as live born (median 52.6%, 90% central range (26.3%, 79.5%)). Consequently, the percentage of infant deaths arising from these births varied (90% central range (6.7%, 31.9%)). Excluding births <24 weeks, led to significant changes in infant mortality rankings of PCTs, with a median worsening of 12 places for PCTs with low rates of live born preterm births <24 weeks of gestation compared with a median improvement of four ranks for those with higher live birth registration rates.

CONCLUSIONS

Infant death rates in PCTs in England are influenced by variation in the registration of births where viability is uncertain. It is vital that this variation is minimised before infant mortality is used as indicator for monitoring health and performance and targeting interventions.

Effectiveness of interventions for the prevention of small-for-gestational age fetuses and perinatal mortality: a review of systematic reviews

Previous narrative reviews in this area have concluded that there are few interventions that are likely to be beneficial and that further high-quality research is required. Our objective was to perform a review of systematic reviews of the effectiveness of interventions for the prevention of small-for-gestational age (SGA) fetuses and perinatal mortality, to summarize the most up-to-date evidence and assess quality. Searches were carried out by using Medline, Embase, Cochrane Library and DARE (inception to September 2011), by hand searching of journal and reference lists and by contact with experts. Systematic reviews of randomized controlled trials were selected. Two reviewers independently selected articles and assessed the methodological and reporting quality. Data were extracted on study characteristics, quality and results. Summary data were presented as relative risks (RRs) and 95% confidence intervals (CIs). There were 834 randomized controlled trials (>668 672 participants), reporting on 45 different interventions. The most effective interventions to prevent the SGA fetus were antiplatelets at <16 weeks in women at risk of pre-eclampsia (RR 0.47; CI 0.30-0.74) and progesterone therapy for prevention of preterm birth (RR 0.64; CI 0.49-0.83). For the prevention of perinatal mortality in high-risk women, antiplatelets (RR 0.69; CI 0.53-0.90) and antenatal corticosteroids (RR 0.77; CI 0.67-0.89) were effective interventions. It is concluded that effective interventions are available for reducing the occurrence of SGA fetuses and preventing related perinatal mortality. Some are effective in all women, while others target specific co-morbidities. There is a need to consider a comprehensive approach to primary prevention that targets SGA along with pre-eclampsia and preterm birth.

Long-term follow-up of 2 newborns with a combined birth weight of 540 grams

Long-term growth and developmental data are presented for the smallest and third smallest surviving newborns in the world literature to 5 and 20 years of age, respectively. Both patients exhibited normal motor and language development. Although head circumference for both newborns demonstrated catchup growth, significant differences in height and weight growth velocities persisted.

Second trimester amniocentesis is not a risk factor for very low birth weight and extremely low birth weight

Objectives. To assess the risk of very low birth weight (VLBW) and extremely low birth weight (ELBW) attributable to second trimester amniocentesis. Methods. Records of 4,877 consecutive amniocentesis, performed between 1997 and 2003, were analyzed. Only VLBW and ELBW in the study population (exposed) and in the control group (unexposed) were evaluated. Comparisons were made between the amniocentesis group versus nonexposed. Odds ratios (OR) and 95% confidence intervals (95% CI) were calculated for VLBW and ELBW classes. Results. In the study population, the VLBW were 35 (0.71%) and the ELBW were 20 (0.41%). In the control group, the VLBW were 220 (0.67%) and the ELBW were 112 (0.34%). The Odds ratios of the VLBW between the study and the control group did not show any statistical significant risk (OR = 1.07, 95% CI = 0.72–1.54). Also in ELBW odds ratios between study and control group were not statistically significant (OR = 1.20, 95% CI = 0.7–1.95). Conclusions. No effect of the second trimester amniocentesis was noted on VLBW and ELBW.

Survival and major disability rate in infant born at 22-25 weeks of gestation

Our aim was to evaluate the literature on survival and major disability rate in preterm infants born at 22- 25 weeks of gestational age (GA). Thirty-three studies were identified and reviewed. Survival was lower in population-based studies (2% at 22, 13% at 23, 35% at 24, and 56% at 25 weeks) than in center-based study (15% at 22, 41% at 23, 58% at 24, and 74% at 25 weeks). The severe disability rate was slightly higher in population-based studies than in center-based studies at 23 (29 vs. 32%) and at 24 (30 vs. 27%) week of GA, whereas it was similar in population and center-based studies at 25 (21 vs. 22%) weeks of GA. Survival rate seems to improve with time, whereas the change of severe disability rate cannot be adequately evaluated due to the paucity of available data. We conclude that the survival of infants born at 22 weeks is still an uncommon event, whereas the survival of infants born at 23, and mostly at 24 and 25 weeks of GA is significant in the majority of studies.

Neonatal management and long-term sequelae

Intrauterine or fetal growth restriction is best defined by using customised birth weight percentiles based upon the growth potential for an individual infant. Growth restriction in utero may be classified as asymmetric or symmetric depending upon the duration of the process. Asymmetric growth restriction is caused by placental insufficiency, maternal hypertensive conditions, long-standing maternal diabetes, smoking, living at altitude or multiple gestation. Symmetric growth restriction may be due to congenital infections, chromosomal or other abnormalities, fetal alcohol syndrome, low socioeconomic status or be constitutional. The underlying cause of growth restriction often predicts the potential adverse effects on the foetus and newborn and later effects in childhood and adulthood. With placental insufficiency, there may be chronic or acute on chronic fetal hypoxia with birth asphyxia and hypothermia, neonatal hypoglycaemia, polycythaemia and coagulopathy. Management is directed at prevention or early treatment of these conditions. In contrast, symmetrically growth-restricted infants should be examined carefully to look for congenital infections and malformations that may need specific interventions. Infants with constitutional short stature generally do not need any specific management. Feeding of growth-restricted infants is important to overcome deficiencies incurred in utero. Most infants show catch-up growth although about 10% do not. Those with excessive catch-up growth may be at greatest risk of developing insulin resistance in adulthood leading to diabetes, obesity and heart disease. The so-called fetal origins of disease may actually have a postnatal onset related more to excessive weight gain in infancy. There is still controversy over the indications for growth hormone treatment in growth-restricted infants who remain of short stature in early childhood. Intrauterine growth restriction is also associated with a five- to seven-fold increased risk of cerebral palsy probably due to chronic placental insufficiency.

[Neonatal and perinatal mortality in hospitals of the Basque Country-Navarre Neonatal Study Group (GEN-VN) during the period 2000-2006]

BACKGROUND

In 2000, the Basque-Navarre Neonatal Study Group (GEN-VN) was created with a clear objective of studying the perinatal and neonatal health outcomes in newborns.

OBJECTIVE

The aim of this investigation is to present the trends of neonatal and perinatal mortality and their causes in the hospitals of the Basque-Navarre Neonatal Study Group from 2000 to 2006.

PATIENTS AND METHOD

A descriptive study was carried out on the 157,623 births in the participating hospitals of the Basque-Navarre Neonatal Study Group, from 2000 to 2006. During this period, of the total births, 156.904 were born alive, there were 719 foetal deaths and 363 newborns died within the first 28 days of life. Perinatal and neonatal mortality was analysed, raw and stratified by gestational age and birth weight.

RESULTS

The Basque -Navarre Neonatal Study Group collects from 80.5% to 96.8% of all the births reported by the authorities. There is a decreasing trend in foetal and perinatal mortality rates from 2000 to 2006. However, neonatal mortality rates shows a stable trend when compared with the descense in the last years of the 20th century. The most frequent causes of death are respiratory, infections and the congenital anomalies.

CONCLUSIONS

Collecting regional data improves the quality of neonatal and perinatal mortality studies. Very low birth weight and very low gestational age newborns require special quality of care due their high mortality (54.8% of neonatal mortality in 2006), therefore further studies are required on the impact of these newborns on neonatal mortality in our hospitals.

The ethics of delivery-room resuscitation

Perinatal care continues to improve and the number of extremely preterm babies delivered increases. What is the outcome for those babies? Under what circumstances should we not initiate resuscitation or under what circumstances should we discontinue support? How accurate and predictive are the data we have and how can these be improved? Who should make the decisions and how should they be made? Should we follow different guidelines in different settings? The following narrative will examine some of these questions but cannot answer them all.

The legal framework for end-of-life decisions in the UK

We have reviewed the current UK guidance regarding withholding and withdrawing life-prolonging treatment in the infant and termination of pregnancy for fetal malformation. We provide summaries of the key cases. The framework provided by professional bodies and the law in this difficult area stresses the importance of good and frequent communication between different professional groups and parents with early recourse to second opinions if a difference of view emerges. Legal proceedings should be used only as a last resort.

The search for objective criteria at the limit of viability

BACKGROUND

Defining the limit of viability among very preterm infants remains a difficult issue. A recent study suggested severity of intrauterine growth retardation as a decisive criterion, reporting very poor survival for infants born at </=28 weeks with birth weight <2nd centile.

OBJECTIVE

To check whether the above criterion can be confirmed in a similar analysis of German data.

METHODS

Analyses were based on German population-based data from Lower Saxony, including preterm neonates (22-28 weeks) without severe congenital malformations (n = 3,453), born 1991-1999. For the definition of growth retardation postnatal (<3rd, <10th centile) and antenatal (<3rd centile) reference values were used.

RESULTS

Depending on the definition used, proportions of growth retarded infants varied considerably (4-16%). Survival rates increased from 0 to 64%, arguing against considering infants <28 weeks' GA as a homogenous group with regard to their odds for survival.

CONCLUSION

There is an association between severity of growth retardation and VLBW mortality in general, but overinterpreting results from single studies may lead to dangerous conclusions. Data from preterm infants should be stratified by week of gestation.

Diagnosis and management of fetal growth restriction: the role of fetal therapy

Fetal growth restriction remains a major cause of perinatal morbidity and mortality in modern obstetric practice. Placental insufficiency is the most common association, but is often a diagnosis of exclusion. Currently, no treatment can ameliorate or reverse established growth restriction: maximising gestational age and judicious timing of steroid administration and delivery are the primary tasks for the obstetrician. Although comprehensive surveillance of the preterm fetus now includes ductus venosus Doppler studies, its effectiveness in timing delivery has yet to be confirmed in randomised controlled trials. More basic research on the regulation of fetal growth is needed before specific therapies for established growth restriction can be developed.