Customised birthweight centiles are useful for identifying small-for-gestational-age babies in women with type 2 diabetes

Background: Customised birthweight centiles identify small-for-gestational-age (SGA) babies at increased risk of morbidity more accurately than population centiles, but they have not been validated in obese populations.
Aims: To compare the rates of SGA by population and customised birthweight centiles in babies of women with type 2 diabetes and examine perinatal outcomes in customised SGA infants.
Methods: Data were from a previous retrospective cohort study detailing pregnancy outcomes in 212 women with type 2 diabetes. Customised and population birthweight centiles were calculated; pregnancy details and neonatal outcomes were compared between groups that delivered infants who were SGA (birthweight < 10th customised centile) and appropriate weight for gestational age (AGA) (birthweight 10–90th customised centile).
Results: Fifteen (7%) babies were SGA by population centiles and 32 (15%) by customised centiles. Two babies of Indian women were reclassified from SGA to AGA by customised centiles. Nineteen babies were reclassified from AGA to SGA by customised centiles; of these, 15 (79%) were born to Polynesian women, five (26%) were born less than 32 weeks and two (11%) were stillborn. Customised SGA infants, compared with AGA infants, were more likely to be born preterm (19 (59%) vs 20 (16%), P  < 0.001) and more likely to be stillborn (4 (13%) vs 0 P  = 0.001). After excluding still births, admission to the neonatal unit was also more common (19 of 28 (68%) vs 43 of 127 (34%), P  < 0.001).
Conclusions: In our population more babies were classified as SGA by customised compared with population centiles. These customised SGA babies have high rates of morbidity.     

Adverse perinatal outcome and maternal risk factors in population versus customized defined SGA babies

Objective.?The purpose of this study was to compare population and customized-based birth weight centiles in their association with perinatal outcome and maternal risk factors, in nulliparous Caucasian women in a socio-economic disadvantaged region.

Methods.?We analyzed perinatal outcomes in births of 302 Caucasian women of which 155 were small for gestational age (SGA) and 147 were appropriate for gestational age (AGA). Out of the overall study group, two cohort studies were designed. One was classified by population centiles as either SGA (n= 133) or AGA (n?= 169) and the other was classified by customized centiles as either SGA (n?= 131) or AGA (n?= 172). Maternal risk factors and operative delivery rates for fetal distress, Apgar scores, need for resuscitation and neonatal nursery care given, were determined for both customized and population-based SGA babies.

Results.?The customized SGA only group showed more mental health problems and special nursery in comparison with the AGA group. The population SGA only group had more smoking and mental health problems than the AGA group, but no differences on neonatal outcome measures.

Conclusion.?Use of customized centiles does identify an additional group neonates with a significantly higher need for special nursery admission in a homogeneous ethnic Caucasian group.     

The value of customised centiles in assessing perinatal mortality risk associated with parity and maternal size

Objective  We wanted to compare customised and population standards for defining smallness for gestational age (SGA) in the assessment of perinatal mortality risk associated with parity and maternal size.
Design  Population-based cohort study.
Setting  Sweden.
Population  Swedish Birth Registry database 1992–1995 with 354 205 complete records.
Method  Coefficients were derived and applied to determine SGA by the fully customised method, or by adjustment for fetal sex only, and using the same fetal weight standard.
Main outcome measure  Perinatal deaths and rates of small for gestational age (SGA) babies within subgroups stratified by parity, body mass index (BMI) and maternal size within the BMI range of 20.0–24.9.
Results  Perinatal mortality rates (PMR) had a U-shaped distribution in parity groups, increased proportionately with maternal BMI, and had no association with maternal size within the normal BMI range. For each of these subgroups, SGA rates determined by the customised method showed strong association with the PMR. In contrast, SGA based on uncustomised, population-based centiles had poor correlation with perinatal mortality. The increased perinatal mortality risk in pregnancies of obese mothers was associated with an increased risk of SGA using customised centiles, and a decreased risk of SGA using population-based centiles.
Conclusion  The use of customised centiles to determine SGA improves the identification of pregnancies which are at increased risk of perinatal death.     

Growth restriction: identifying fetuses at risk

Purpose: Examine risks of intrauterine growth restriction (IUGR) and composite perinatal outcomes with estimated fetal weights (EFW) 10–20th%, and compare outcomes using umbilical artery Doppler (UAD).

Materials and methods: Retrospective, cohort evaluating ultrasound (US) EFW 10–20th%, between 2002 and 2012. Cases were identified with EFW % 10–20. Controls, EFW?>20th% were obtained for each case, matched by gestational age, and US date. Unadjusted and adjusted logistic regression was used for outcomes.

Results: Seven hundred and sixty-seven cases met criteria with matched controls. Fetuses having EFW 10–20th% (GA 33.6?±?3.7 weeks) had increased IUGR on follow up ultrasound (OR 26.5[10.2–68.7], p?p?p?p?p?Conclusions: Pregnancies with EFW 10–20th% at the time of initial US are at increased risk for developing IUGR and being SGA at birth, with more NICU admissions and composite perinatal outcomes; abnormal UAD evaluation in cases conveyed further increase in outcomes.     

Antiphosphatidyl serine antibodies are more common in normotensive women with small for gestational age pregnancies

BACKGROUND: Small for gestational age (SGA) babies are more common in women with antiphospholipid antibodies but data are limited about the prevalence of antiphospholipid antibodies in women who have delivered SGA babies. AIM: To determine whether elevated levels of anticardiolipin, antiphosphatidyl serine and/or antibeta2 glycoprotein I antibodies are more common in normotensive women who delivered SGA babies compared with women who delivered appropriate for gestational age babies. METHODS: Case-control study. Cases were normotensive women who delivered an SGA baby (birthweight <10th%) without chromosomal or congenital abnormality. Controls were healthy women who delivered a baby at term with birthweight >10th percentage. RESULTS: A total of 137 women with SGA pregnancies and 290 controls had antiphospholipid antibodies measured. The prevalence of anticardiolipin and antibeta2 glycoprotein I antibodies did not differ between SGA cases and controls. Antiphosphatidyl serine IgG antibodies were more common in women with SGA pregnancies than controls seven (5%) versus five (1.7%), relative risk (RR) 1.84 (1.12-3.03). There was no difference in the prevalence of 'any antiphospholipid antibodies' between SGA 10 (7.2%) and controls 16 (5.6%). There was a trend to more abnormal umbilical Doppler studies in SGA pregnancies with positive antiphospholipid antibodies three (50%) versus 19 (24%), RR 2.9 (0.62-13). CONCLUSIONS: Antiphospholipid antibodies were uncommon in this cohort of SGA pregnancies. Further studies are needed in SGA pregnancies with abnormal umbilical Doppler studies to determine if screening for antiphospholipid antibodies is worthwhile in this severe subgroup.     

Predictiveness of antenatal umbilical artery Doppler for adverse pregnancy outcome in small-for-gestational-age babies according to customised birthweight centiles: population-based study

Objective  To examine the relationship between smallness at birth and the predictive value of umbilical artery Doppler.
Design  Retrospective cohort.
Setting  Tertiary referral university hospital, Barcelona.
Population  A total of 7645 singleton pregnancies delivered between January 2002 and June 2004.
Methods  The associations with adverse outcome were assessed for small-for-gestational-age (SGA) babies according to customised standards who had normal and abnormal umbilical artery Doppler.
Main outcome measures  Neonatal morbidity and perinatal mortality.
Results  Of the 369 SGA fetuses that had been identified antenatally, 70 (19%) had an abnormal umbilical artery Doppler and the babies from these pregnancies had a higher risk for neonatal morbidity when compared with babies with normal birthweight (OR 3.99, 95% CI 1.04–11.03). However, the remaining 299 (81%) fetuses with normal umbilical artery Doppler also had an elevated risk of neonatal morbidity (OR 2.26, 95% CI 1.04–4.39). Overall, many of the instances of adverse outcome associated with smallness for gestational age were attributable to the group with normal Doppler than to the group with abnormal Doppler.
Conclusion  Normal antenatal umbilical artery Doppler cannot be taken as an indicator of low risk in pregnancies where the fetus is SGA according to customised percentiles.     

Fetal growth restriction and other risk factors for stillbirth in a New Zealand setting

BACKGROUND: Stillbirth affects almost 1% of pregnant women in the Western world but is still not a research priority. AIMS: To assess in a cohort of stillbirths: the demographic risk factors, the prevalence of small for gestational age (SGA) by customised and population centiles, and the classification of death using the Perinatal Society of Australia and New Zealand Perinatal Death Classification (PSANZ-PDC). METHODS: The study population comprised 437 stillborn babies (born from 1993 to 2000 at National Women's Hospital, Auckland, New Zealand) and their mothers. The referent population for demographic factors was live births n=69 173. RESULTS: After multivariable analysis, risk factors for stillbirths were: Indian (odds ratio (OR) 1.85, 95%CI (1.18, 2.91)), or Pacific Islander (OR 1.65, 95%CI (1.27, 2.14)); smoking (OR 1.33, 95%CI (0.99, 1.79)) or unknown smoking status (OR 2.87, 95%CI (2.30, 3.58)); nulliparity (OR 1.42, 95%CI (1.10, 1.83)), and para 2 (OR 1.36, 95%CI (1.01, 1.83)). One hundred and twenty-nine (46%) stillbirths born>or=24 weeks (n=278) were SGA by customised, and 94 (34%) by population centiles. Customised SGA was more common in preterm versus term stillbirths (101 of 198 (51%) vs 28 of 80 (35%), respectively, P=0.02) but rates of population SGA did not differ (72 of 198 (36%) vs 22 of 80 (28%) P=0.16). 'Spontaneous preterm' was the most common cause of stillbirth at <28 weeks and 'unexplained' at >or=28 weeks using PSANZ-PDC classification. CONCLUSIONS: This study again emphasises the importance of suboptimal fetal growth as an important risk factor for stillbirth. Customised centiles identified more stillborn babies as SGA than population centiles especially preterm.     

Should parity be included in customised fetal weight standards for identifying small-for-gestational-age babies? Results from a French multicentre study

Objective  Parity is one of several parameters used to customise fetal growth norms. However, it is uncertain whether the lower birthweight of babies born to primiparous women reflects physiological or pathological variation. Our aim was to assess the impact of adjusting for parity in identification of small-for-gestational-age (SGA) births.
Design  Comparison of two customised definitions of SGA with and without parity.
Setting  Routinely collected data in five tertiary maternity hospitals in France.
Population  A total of 51 126 singleton births without malformations from 1997 to 2002.
Methods  Characteristics of mothers and babies and adverse pregnancy outcomes for SGA and non-SGA births were compared using customised definitions with and without parity.
Main outcome measures  Neonatal morbidity and mortality.
Results  SGA births among primiparas increased from 14.9 to 18.0% when parity was excluded. Overall rates of SGA rose from 14.4 to 15.0%. Newly defined cases of SGA were babies of primiparas. They had higher rates of admission to a neonatal unit and caesarean section than babies reclassified as non-SGA. Perinatal mortality was 9.1‰ (parity included) and 9.7‰ (parity excluded) and did not differ significantly from babies classified as non-SGA by both standards (5.4‰).
Conclusions  Adjustment for parity markedly decreased the proportion of primiparas diagnosed with SGA babies but did not appear to improve the identification of high-risk babies. Removing parity would simplify the customised definition of SGA and would eliminate the need for the assumption that lower birthweight for primiparous women is normal.     

Association between pregnancy complications and small-for–gestational-age birth weight defined by customized fetal growth standard versus a population-based standard

Objective.?To derive coefficients for developing a customized growth chart for a Mid-Western US population, and to estimate the association between pregnancy outcomes and smallness for gestational age (SGA) defined by the customized growth chart compared with a population-based growth chart for the USA.

Method.?A retrospective cohort study of an ultrasound database using 54,433 pregnancies meeting inclusion criteria was conducted. Coefficients for customized centiles were derived using 42,277 pregnancies and compared with those obtained from other populations. Two adverse outcome indicators were defined (greater than 7 day stay in the neonatal unit and stillbirth [SB]), and the risk for each outcome was calculated for the groups of pregnancies defined as SGA by the population standard and SGA by the customized standard using 12,456 pregnancies for the validation sample.

Results.?The growth potential expressed as weight at 40 weeks in this population was 3524?g (standard error: 402?g). In the validation population, 4055 cases of SGA were identified using both population and customized standards. The cases additionally identified as SGA by the customized method had a significantly increased risk of each of the adverse outcome categories. The sensitivity and specificity of those identified as SGA by customized method only for detecting pregnancies at risk for SB was 32.7% (95% confidence interval [CI] 27.0–38.8%) and 95.1% (95% CI: 94.7–95.0%) versus 0.8% (95% CI 0.1–2.7%) and 98.0% (95% CI 97.8–98.2%)for those identified by only the population-based method, respectively.

Conclusion.?SGA defined by customized growth potential is able to identify substantially more pregnancies at a risk for adverse outcome than the currently used national standard for fetal growth.     

Small for gestational age preterm infants and relationship of abnormal umbilical artery Doppler blood flow to perinatal mortality and neurodevelopmental outcomes

Aim: To determine the outcomes of preterm small for gestational age (SGA) infants with abnormal umbilical artery (UA) Doppler studies.
Methods: A retrospective cohort study of SGA singleton infants delivered between 24 and 32 weeks gestation at King Edward Memorial Hospital, Perth, who had UA Doppler studies performed within seven days of birth. Main outcomes assessed were perinatal mortality and morbidity, and neurodevelopmental outcomes at ≥ 1 year of age. Outcomes were compared by normality of UA blood flow.
Results: There were 119 infants in the study: 49 (41%) had normal UA Doppler studies, 31 (26%) had an increased systolic–diastolic ratio ≥ 95th centile, 19 (16%) had absent end diastolic blood flow (AEDF) and 20 (17%) had reversed end-diastolic flow (REDF). Infants in the AEDF and REDF groups were delivered significantly more preterm ( P  = 0.006) and had lower birthweights ( P  < 0.001). Ninety four per cent (110 of 117) of live born infants survived. Neurodevelopmental follow-up at 12 months of age or more (median 24 months) was available on 87 of 108 (81%) of live children. Twenty-eight per cent (11 of 39) of fetuses who had had AEDF or REDF died or were classified with moderate or severe disability. There was no significant association between abnormality of UA blood flow, perinatal morbidity, perinatal mortality and neurodevelopmental disability after correction for gestational age.
Conclusion: Fetuses that are SGA with abnormal UA Doppler studies remain at significant risk of perinatal death, perinatal morbidity and long-term neurodevelopmental disability, associated with their increased risk of preterm birth.     

A comparison of customized and population-based birth-weight standards: The influence of gestational age

Objectives

We examined how customized birth-weight standards compare to population birth-weight references at term (≥37 weeks), nearly term (34–36 weeks), moderately preterm (32–33 weeks) and for the very preterm births (28–31 weeks), with respect to perinatal mortality.

Study design

Data from the national Swedish Medical Births Register for the years 1992–2001, consisting of a total of 783,303 singletons born at or after 28 completed gestational weeks. Infants were classified as small for gestational age (SGA, <10th centile) according to a conventional population based birth-weight reference and a customized standard. Risk ratios (RR) for still birth and neonatal death were compared between standards by prematurity of the birth. Diagnostic performance measures of specificity, sensitivity and positive and negative predictive values were also evaluated.

Results

More than half, 59% (209), of the 355 infants still-born between 28 and 31 weeks gestation were classified as SGA by the customized standard, but only 23% (80), were so classified as SGA by the population reference. However, only 14% (95%CI 13–16) of the 1461 very preterm infants classified as SGA by the customized standard were still-born, compared to 23% (95%CI 19–28) of the 348 infants classified as SGA by the population reference. Therefore, the relative risk of still birth for those classified as SGA by the customized standard is lower, 2.02 (95%CI: 1.65, 2.46), than for the population reference 2.64 (95%CI: 2.11, 3.30). Similar results were observed for the risk of neonatal death. For term weeks, customized standards showed stronger relationships than population references (RR: 4.30 (95%CI 3.82, 4.84) vs. 4.00 (95%CI 3.55, 4.51) for still births).

Conclusions

Customized standards categorize a higher absolute number of preterm infants who are still-born as SGA. However, infants classified as SGA by population references are at higher risk of perinatal mortality than infants classified as SGA by customized standards.     

An audit of the detection and management of small-for-gestational age babies

Summary. The detection and management of small-for-gestational age babies (SGA) was assessed in a case record review of 1302 randomly selected pregnancies. Of the 129 babies with birthweights below the 10th centile for gestational age, 34 (26%) were identified antenatally. For every two correctly identified SGA babies there were three false positive predictions. In-patient monitoring and early elective delivery occurred both in the correctly identified pregnancies (24%) and in the false positives (12%). The management of suspected pregnancies bore no apparent relation to test results and appeared arbitrary. Mortality and morbidity, as measured by nursery admission for >48 h and retention in the nursery after the mother's discharge, were higher in SGA babies than in the hospital population as a whole. The number of ill babies was small, however, reflecting the heterogeneous aetiology of small size for gestational age. Moreover, antenatal detection had little influence on these measures of outcome. It is concluded that tests for detection of SGA babies remain imprecise in practice, gestational weight alone correlates poorly with fetal well-being, and the need remains for sensitive tests to detect babies with genuine morbidity.     

An audit of the detection and management of small-for-gestational age babies

The detection and management of small-for-gestational age babies (SGA) was assessed in a case record review of 1302 randomly selected pregnancies. Of the 129 babies with birthweights below the 10th centile for gestational age, 34 (26%) were identified antenatally. For every two correctly identified SGA babies there were three false positive predictions. In-patient monitoring and early elective delivery occurred both in the correctly identified pregnancies (24%) and in the false positives (12%). The management of suspected pregnancies bore no apparent relation to test results and appeared arbitrary. Mortality and morbidity, as measured by nursery admission for greater than 48 h and retention in the nursery after the mother's discharge, were higher in SGA babies than in the hospital population as a whole. The number of ill babies was small, however, reflecting the heterogeneous aetiology of small size for gestational age. Moreover, antenatal detection had little influence on these measures of outcome. It is concluded that tests for detection of SGA babies remain imprecise in practice, gestational weight alone correlates poorly with fetal well-being, and the need remains for sensitive tests to detect babies with genuine morbidity.     

Effectiveness of detection of intrauterine growth retardation by abdominal palpation as screening test in a low risk population: an observational study

OBJECTIVE: To evaluate the performance of abdominal palpation as a screening test for intrauterine growth retardation (IUGR) in a low risk population, under standard practice conditions. STUDY DESIGN: Population based observational study of 6318 consecutive low risk singleton pregnancies. The Dutch obstetric system distinguishes low from high risk pregnancies. In the low risk group abdominal palpation as a screening test is performed by midwives. If a complication, like IUGR, during prenatal care is assessed, the women is referred to a consulted obstetrician. Ultrasound is performed by the consulted obstetrician. In case of sustained suspicion the women is selected as high risk. Outcome parameters: severe small for gestational age (SGA) birthweight below 2.3rd centile, all SGA birthweight below 10th centile, operative delivery, neonatal morbidity and perinatal mortality. Screening value of abdominal palpation, abdominal palpation combined with ultrasound, and the performance of high risk selection was assessed by conventional performance measures. RESULTS: Abdominal palpation as a screening test for IUGR is of limited value: the observed sensitivities were 28% for severe SGA and 21% for SGA p < or = 10, respectively. After ultrasound in case of sustained suspicion, the sensitivity in detection of severe SGA was 25% and positive predictive value (PPV) 16%. In detection of SGA p < or = 10 sensitivity was 15% and PPV 55%, which means 45% were false positives. The sensitivity of the Dutch obstetric system in selection of high risk pregnancies in detection of severe SGA was 53%, in detection of SGA p < or = 10 was 37%. Perinatal mortality was 0.9% (57/6318) and 32% of these cases were SGA. Six cases of fetal death were unrecognised during prenatal care (0.09%) and seem preventable. The prevalence of a 5 min Apgar Score < or = 7 was significantly higher in the SGA infants if SGA was defined as p < or = 10. CONCLUSIONS: The diagnostic performance of abdominal palpation as a screening test for IUGR detection in a low risk population is disappointing. However, various stratagems such as routine ultrasound do not improve detection rate or perinatal morbidity and mortality.     

Application of a customised birthweight standard in the assessment of perinatal outcome in a high risk population

Objective Physiological as well as pathological variables influence birthweight. The aim of the present study was to examine perinatal outcome in relation to birthweight centiles applying a customised birthweight standard.
Methods Two hundred and seventeen babies from high risk pregnancies were evaluated and classified as small or not small for gestational age according to two standards: 1. conventional Dutch birthweight centiles and 2. customised centiles which adjust individually for physiological variables like maternal booking weight, height and ethnic origin.
Results Customisation of the weight standards resulted in identification of an additional group of infants who were small for gestational age, but not by the Dutch standards. These babies were associated with significantly more adverse perinatal events than those who were not small for gestational age as defined by a customised standard.
Conclusions Adjustment of birthweight centiles for physiological variables significantly improves the identification of infants who have failed to reach the expected birthweight and who are at increased risk for adverse perinatal events.     

Doppler ultrasonography in singleton pregnancies at risk of intrauterine growth retardation-- a national estimate

BACKGROUND: In order to assess the organizational and economical implications of Doppler ultrasonography used in high risk pregnancies, a national estimate of the use in singleton pregnancies with risk of small for gestational age (>2 SD below mean birthweight) (SGA) or intrauterine growth retardation (IUGR) was needed. METHODS: Through retrospective analyzes of both national registry data, and local clinical and ultrasonic records from Copenhagen University Hospital annual populations of singleton pregnant women with suspected IUGR and/or infants born SGA were described. The antenatal care program for assessing pregnancies with suspected IUGR was described. RESULTS: In 1996 2.8% of all singleton infants were born SGA. The population had increased risk of perinatal mortality and morbidity, and about 40% had labor induced or were delivered by caesarean section, compared to 15% of the infants with normal birthweight. In the local population 79 (3.3%) of singleton infants were born SGA and 2/3 of these were considered SGA or IUGR before delivery. Of all singleton pregnancies, a total of 88 (3.7%) were assessed by ultrasonic fetometry because of a risk or clinical suspicion of SGA, and 49 (55.7%) of these pregnancies resulted in a SGA infants. Combining national and local data it is estimated that in Denmark, about 2000 women (3.1%) will be referred for ultrasonic fetometry each year because of a risk or clinical suspicion of SGA and have a mean of 2.5 fetometries. About 75% (1500) will be further assessed by Doppler ultrasonography and have a mean of 3.4 Doppler examinations. CONCLUSION: The annual number of Doppler ultrasonography examinations in singleton pregnancies with increased risk of or signs of IUGR is estimated to be about 5000.     

Early fetal size and growth as predictors of adverse outcome

OBJECTIVE: To evaluate the association between fetal size and growth between the first and second trimesters and subsequent adverse pregnancy outcome. METHODS: A cohort was created of 7,642 singleton pregnancies cared for in three obstetric units associated with Copenhagen University. Data were obtained from ultrasound measurements at 11-14 weeks (crown-rump length, biparietal diameter) and 17-21 weeks (biparietal diameter). Fetal size was assessed by gestation-specific z scores, and fetal growth between the first and second trimester was calculated individually using conditional centiles. The main outcome measures were preterm delivery, smallness for gestational age, and perinatal death. RESULTS: Slow growth of the biparietal diameter less than the 10th and less than the 2.5th conditional centiles between first and second trimesters occurred in 10.4% and 3.6% of the population, respectively. Biparietal diameter growth less than the 10th centile was associated with perinatal death before 34 weeks (risk 0.5% compared with 0.04%, odds ratio [OR] 16.0, confidence interval [CI] 2.9-88.7). Biparietal diameter growth less than the 2.5th centile was the best predictor of perinatal death at any gestation, with a positive likelihood ratio of 4.7 and an OR of 7.3 (CI 2.4-22.2). In contrast, the biparietal diameter, dated by crown-rump length, did not have an increased risk of perinatal death; however, there was a mildly increased risk of small for gestational age birth weight (less than the 10th customized centile) if the biparietal diameter was below the 10th centile in the first trimester (risk 17% compared with 12%, OR 1.5, CI 1.2-1.8) or in the second trimester (risk 15.8% compared with 12.4%, OR 1.3, CI 1.1-1.5). CONCLUSION: Slow growth of the fetal biparietal diameter between the first and second trimesters of pregnancy is a strong predictor of perinatal death before 34 weeks.     

Population-based study on antenatal corticosteroid treatment in preterm small for gestational age and non-small for gestational age twin infants

Objectives: To assess the associations between antenatal corticosteroid use (ACU), mortality and severe morbidities in preterm, twin neonates and compare these between small for gestational age (SGA) and non-SGA twins.

Materials and methods: Population-based study using data collected by the Israel National Very Low Birth Weight infant database from 1995 to 2012, comprising twin infants of 24–31 weeks' gestation, without major malformations. Univariate and multivariable logistic regression analyses were performed.

Results: Among the 6195 study twin infants, 784 were SGA. Among SGA neonates, ACU were associated with decreased mortality (23.9% vs. 39.2%, p?p?=?0.0015), similar to the effect in non-SGA neonates (mortality 13.0% vs. 24.5%, p?p?P_interaction?=?0.69. Composite adverse outcome risk was also reduced in SGA (OR?=?0.78, 95% CI 0.50–1.23) and non-SGA groups (OR?=?0.78, 95% CI 0.65–0.95), P_interaction?=?0.95.

Conclusions: ACU should be considered in all mothers with twin gestation, at risk for preterm delivery at 24–31 weeks, in order to improve perinatal outcome.     

Effect of labor on infant morbidity and mortality with preterm premature rupture of membranes: United States population-based study

OBJECTIVE: To evaluate whether labor, in the setting of premature rupture of membranes (PROM), affects infant morbidity and mortality rates. METHODS: We derived data for this population-based cohort study from the United States national linked birth infant death data sets, comprised of singleton live births delivered between 1995 and 1997. We included women (n = 34,594) who had preterm PROM more than 12 hours and delivered between 23 and 32 weeks' gestation. Birth records were used to determine whether delivery occurred with or without labor. Infants with birth weights below the tenth percentile for gestational age were classified as small for gestational age (SGA) on the basis of a nomogram of all singleton births in the United States between 1995 and 1997. Primary outcomes were early neonatal (0-6 days), late neonatal (7-27 days), postneonatal (28-365 days), and infant death (0-365 days). Secondary outcomes included respiratory distress syndrome (RDS), assisted ventilation, and neonatal seizures. Risks of infant mortality and morbidity from labor were examined separately for SGA and non-SGA infants. RESULTS: Overall rates were infant death 11.6%, RDS 15.1%, assisted ventilation 25.9%, and neonatal seizure 0.2%. Labor was associated with higher incidence of early neonatal death in SGA infants (adjusted relative risk [RR] 1.24, 95% confidence interval [CI] 1.11, 1.38) but had no effect on other outcomes. Among non-SGA infants, labor had no effect on infant death but was associated with higher rates of RDS (RR 1.15, 95% CI 1.08, 1.22) and assisted ventilation (RR 1.16, 95% CI 1.08, 1.24). CONCLUSION: Although labor was associated with a slightly higher mortality rate in SGA infants and slightly more respiratory morbidity in non-SGA infants, recommendations regarding clinical treatment should await future clinical trials.     

Neonatal outcomes of small for gestational age preterm infants in Canada

To compare the effect of small for gestational age (SGA) on mortality, major morbidity and resource utilization among singleton very preterm infants (<33 weeks gestation) admitted to neonatal intensive care units (NICUs) across Canada. Infants admitted to participating NICUs from 2003 to 2008 were divided into SGA (defined as birth weight <10th percentile for gestational age and sex) and non-small gestational age (non-SGA) groups. The risk-adjusted effects of SGA on neonatal outcomes and resource utilization were examined using multivariable analyses. SGA infants (n = 1249 from a cohort of 11,909) had a higher odds of mortality (adjusted odds ratio [AOR] 2.46; 95% confidence interval [CI], 1.93-3.14), necrotizing enterocolitis (AOR 1.57; 95% CI, 1.22-2.03), bronchopulmonary dysplasia (AOR 1.78; 95% CI, 1.48-2.13), and severe retinopathy of prematurity (AOR 2.34; 95% CI, 1.71-3.19). These infants also had lower odds of survival free of major morbidity (AOR 0.50; 95% CI, 0.43-0.58) and respiratory distress syndrome (AOR 0.79; 95% CI, 0.68-0.93). In addition, SGA infants had a more prolonged stay in the NICU, and longer use of ventilation continuous positive airway pressure, and supplemental oxygen (p < 0.01 for all). SGA infants had a higher risk of mortality, major morbidities, and higher resource utilization compared with non-SGA infants.