Association of BNT162b2 SARS-CoV-2 vaccination during pregnancy with postnatal outcomes in premature infants.

AIM: The effect of COVID-19 vaccine given during pregnancy on premature infants is unknown. This study aims to determine the association between maternal COVID-19 vaccine with postnatal outcome in premature infants. METHODS: This is a single-centre retrospective case-control study of infants born before 35 weeks gestation to mothers who received SARS-CoV-2 vaccine during pregnancy compared with infant born to non-vaccinated mothers. RESULTS: A total of 78 infants in each group were included. Infants in the vaccinated group had less respiratory distress syndrome (RDS) (p = 0.02) and less need for respiratory support (p = 0.002), and maternal vaccine had a protective effect on RDS [adjustable OR 0.38 (0.17-0.85)]. Vaccination during the first compared to the second trimester was associated with earlier gestational age (32.3 ± 2.1 vs. 33.3 ± 1.1 weeks, p = 0.03). CONCLUSION: We demonstrated that maternal SARS-CoV-2 vaccine is not associated with postnatal adverse effect in premature infants and potentially has a protective effect on RDS. Earlier gestational age among the infants born to mothers who received COVID-19 vaccine during the first trimester did not translate to higher rate of postnatal complications. These findings might suggest that COVID-19 vaccine is safe in high-risk pregnancies, but timing of administration should be considered. Further studies are needed to confirm our findings and the biological mechanism.

The Clinical Significance of Extreme Leukocytosis among Newborns: A Retrospective Cohort Study.

OBJECTIVE: The aim of the study is to examine the clinical significance of extreme leukocytosis (>40,000 cells/µL) at birth among neonates. STUDY DESIGN: Data were retrospectively collected on 208 infants with leukocytosis >40,000 cells/µL and on matched normal controls as determined in complete blood counts obtained on the first day of life. RESULTS: There were no significant group differences in birth weight, Apgar's score, timing of respiratory support, hospitalization in special care units or rehospitalization during the first month of life. All neonates with leukocytosis received antibiotics. The blood cultures of both groups were negative. A multivariate analysis showed that leukocytosis did not predict either the presence of symptoms associated with sepsis among neonates or hospitalization in a neonatal special care unit. CONCLUSION: Extreme leukocytosis on the first day of life is a poor predictor of infection. Clinicians should decide upon treatment according to risk factors and symptoms but not according to the degree of leukocytosis. KEY POINTS: · Extreme leukocytosis on the first day of life is a poor predictor of infection.. · Clinicians should decide upon treatment according to risk factors and symptoms.. · Leukocytosis was not predictive of a higher risk of morbidity in neonates..

Increased risk for early hypertriglyceridemia in small for gestational age preterm infants.

Small for gestational age preterm are at increased risk for future metabolic syndrome. Early indication for the disrupted metabolism may be found in the perinatal period. We aimed to evaluate whether small for gestational age preterm infants are at increased risk for hypertriglyceridemia when treated with lipid emulsions, and to investigate the association between triglyceride levels and morbidity. Small for gestational age infants ≤ 34 weeks' gestation age born during 2013-2016 were matched and compared with appropriate for gestational age counterparts. Triglyceride concentration > 250 mg/dL during treatment with parenteral nutrition was considered high. The study included 71 pairs of preterm infants. Hypertriglyceridemia was documented among 22.5% of the small for gestational age infants vs. 5.6% of the appropriate for gestational age infants (p = 0.007). Mean triglyceride levels were 194.4 ± 192.3 mg/dL and 99.9 ± 82.8 mg/dL, respectively (p < 0.001). Small for gestational age was predictive of hypertriglyceridemia (OR = 6.41; 95% CI 1.8-22.9). No significant association was found between triglyceride levels and morbidities in multivariate analysis.Conclusion: Small for gestational age preterm infants receiving lipid emulsions might be at a higher risk for hypertriglyceridemia. Routine monitoring of triglyceride levels will enable identification of the necessity for a slower increase in lipid emulsion therapy. What is Known: • Moderate and very preterm infants are routinely treated with lipid emulsions. • Small for gestational age (SGA) infants may have different metabolism, as they demonstrate higher risk for metabolic syndrome. What is New: • • SGA infants had a higher mean triglyceride level and more commonly had early hypertriglyceridemia (triglycerides > 250 mg/dL) compared with appropriate for gestational age infants treated with the same intravenous lipid dose. Small for gestational age was predictive of hypertriglyceridemia. • No significant association was found between triglyceride levels and morbidities in multivariate analysis.

The association between novel glucose indices in parturients with type 1 diabetes mellitus and clinically significant neonatal hypoglycemia.

The aim of this study was to determine the association between glucose control indices of parturient with type 1 diabetes (T1DM), treated with an insulin pump and utilizing continuous glucose monitoring (CGM), and clinically significant neonatal hypoglycemia. This was a retrospective cohort study which included 37 pregnant women with T1DM. All women were followed at a single tertiary center and had available CGM data. The association between maternal glucose indices before delivery and the risk for neonatal hypoglycemia requiring IV glucose (clinically significant hypoglycemia) was assessed using logistic regression. Mothers to neonates that experienced clinically significant hypoglycemia had a higher glucose standard deviation (SD) before delivery than did mothers to neonates who did not (25.5 ± 13 mg/dL vs. 14.7 ± 6.7 mg/dl respectively; p = .008). This association persisted after adjustment for maternal age, maternal pregestational body mass index (BMI), gestational age at delivery, neonatal birth weight, large for gestational age (LGA) and gender. This study demonstrates an association between high maternal glucose standard deviation before delivery and the risk for clinically significant neonatal hypoglycemia. Larger studies are needed to confirm these results and further explore the role of intrapartum glucose variability in the prediction and prevention of significant neonatal hypoglycemia.

Short-Term Neonatal Outcome among Term Infants after In-Utero Exposure to Beta Blockers.

BACKGROUND: The need for postnatal monitoring of infants exposed to intrauterine beta blockers (BBs) has not been clearly defined. OBJECTIVES: To evaluate infants exposed to intrauterine BBs in order to estimate the need for postnatal monitoring. METHODS: This retrospective case-control study comprised 153 term infants born to mothers who had been treated with BBs during pregnancy. Treatment indications included hypertension 76 mothers (49.7%), cardiac arrhythmias 48 (31.4%), rheumatic heart disease 14 (9.1%), cardiomyopathy 11 (7.2%) and migraine 4 (2.6%). The controls were infants of mothers with hypertension not exposed to BBs who were born at the same gestational age and born closest (before or after) to the matched infant in the study group. RESULTS: Compared to the control group, the infants in the study group had a higher prevalence of early asymptomatic hypoglycemia (study 30.7% vs. control 18.3%, P = 0.016), short symptomatic bradycardia events, other cardiac manifestations (P = 0.016), and longer hospitalization (P < 0.001). No life-threatening medical conditions were documented. The birth weight was significantly lower for the high-dose subgroup compared to the low-dose subgroup (P = 0.03), and the high-dose subgroup had a higher incidence of small-for-gestational-age (P = 0.02). CONCLUSIONS: No alarming or life-threatening medical conditions were observed among term infants born to BB treated mothers. These infants can be safely observed for 48 hours after birth close to their mothers in the maternity ward. Glucose follow-up is needed, especially in the first hours of life.

Tumor-associated and disease-associated autoantibody repertoires in healthy colostrum and maternal and newborn cord sera.

In this work, we studied autoantibody repertoires and Ig isotypes in 71 mothers and their 104 healthy newborns (including twins and triplets delivered term or premature). Newborns receive maternal IgG Abs via the placenta before birth, but developing infants must produce their own IgM and IgA Abs. We used an Ag microarray analysis to detect binding to a selection of 295 self-Ags, compared with 27 standard foreign Ags. The magnitude of binding to specific self-Ags was found to be not less than that to the foreign Ags. As expected, each newborn shared with its mother a similar IgG repertoire-manifest as early as the 24th week of gestation. IgM and IgA autoantibody repertoires in cord sera were highly correlated among the newborns and differed from their mothers' repertoires; the latter differed in sera and milk. The autoantibodies bound to self-Ags known to be associated with tumors and to autoimmune diseases. Thus, autoantibody repertoires in healthy humans--the immunological homunculus--arise congenitally, differ in maternal milk and sera, and mark the potential of the immune system to attack tumors, beneficially, or healthy tissues, harmfully; regulation of the tissue site, the dynamics, and the response phenotype of homuncular autoimmunity very likely affects health.

Short-Term Perinatal Outcome among Term Infants with Prenatal Diagnosis of Large Abdominal Circumference.

Background Measuring fetal abdominal circumference (AC) prenatally is an effective tool for predicting neonatal weight and macrosomia. Data are lacking regarding the outcome of newborn infants with prenatal diagnosis of large AC. Aim The aim of this study was to evaluate early short-term neonatal outcome among term singleton newborn infants with prenatal diagnosis of large AC. Methods Retrospective data were collected on 501 term infants with prenatal diagnosis of large AC (≥ 360 mm) and on matched controls, including information on maternal condition and on infant perinatal complications. Results In compare with controls, the study group had higher incidence of macrosomia (188 [37.5%] vs. 18 [3.6%], p < 0.001), hypoglycemia (48 (9.6%) vs. 25 [5%], p = 0.007), and significant morbidity (49 [9.8%] vs. 28 [5.6%], p = 0.017) but without increased incidence of congenital malformations or other perinatal complications. Only among the macrosomic, study subgroup and their controls differences were recorded including hypoglycemia (17.6 vs. 4.8%, p < 0.001), need for oral glucose (11.2 vs. 2.7%, p = 0.002), significant morbidity (10.1 vs. 3.7%, p = 0.024), and hospitalization in special care unit (11.7 vs. 4.3%, p = 0.012). Conclusion Prelabor diagnosis of large AC mostly reflects the infant's high birth weight and macrosomia with the associated perinatal complications. Large AC by itself was not predictive of any congenital malformations or perinatal and postnatal complications.

Indication of Mild Hemolytic Reaction Among Preterm Infants With ABO Incompatibility.

BACKGROUND: Among term infants, ABO incompatibility is a leading cause of hemolytic disease and neonatal jaundice. With respect to preterm infants, data are lacking. OBJECTIVE: To evaluate the incidence and severity of ABO incompatibility hemolytic disease among preterm infants with respect to hemolytic and jaundice parameters. DESIGN: Clinical and laboratory data were collected retrospectively from the medical records of 118 ABO-incompatible preterms born at gestational age (GA) 29-34 weeks, as well as 118 controls matched for GA, birth weight, and multiplicity. All infants were born at the Sheba Medical Center Tel-Hashomer between 2009 and 2012. RESULTS: The study and control groups were similar on all maternal and neonatal outcome parameters. No differences between the groups were recorded throughout hospitalization regarding hematocrit levels or the need for blood transfusion. Bilirubin levels were higher among the study (ABO-incompatible) group during the first 10 days of life; however, no significant differences were found regarding the need for phototherapy. Upon evaluating subgroups divided by GA, we found no differences on any hematological and jaundice factors among preterms of 29-31 weeks, whereas among preterms of 32-34 weeks higher positive direct antiglobulin test (DAT) results (7% vs. 0% in the control, P = 0.014) as well as higher bilirubin levels were documented. CONCLUSIONS: Among ABO-incompatible preterm infants with GA 29-34 weeks, there is no evidence of significant hemolytic reaction derived from placental transfer of antibodies. With increasing GA, antibody transfer becomes more significant, resulting in more positive DAT results and greater incidence of neonatal jaundice.

Which Anthropometric Measure Best Correlates with Neonatal Fat Mass at Birth?

Objective Body composition provides additional information than weight alone. There is currently no accepted anthropometric measure of adiposity in infants, yet weight and length data allow calculations of a wide array of indices. The study objective was to identify the anthropometric index which best correlates with neonatal adiposity, by examining the associations between neonatal fat mass and several anthropometric indices of newborn infants. Study Design The sum of skinfolds (SSF), birth weight, and birth length were measured in 94 healthy infants (58% males) born at term to healthy mothers. Several anthropometric indices were calculated, and their relationship with SSF was assessed using linear regression adjusting for gestational age and sex. Results SSF at birth was significantly higher in females compared with males (20.7 ± 3.3 vs. 18.8 ± 4.1 mm, p = 0.019). Birth weight, birth weight-for-gestational-age percentile, birth weight percentile, and weight/length ratio had the highest associations with SSF, yet R (2) values were very low, ranging from 16 to 18%. Body mass index (BMI), BMI percentile, ponderal index, and the symmetry index had even lower associations. Conclusion No anthropometric measure can confidently assess fat mass in infants at birth, in accordance with previous research. When body composition data are needed, they should be directly measured.

Gestational weight gain and body mass indexes have an impact on the outcomes of diabetic mothers and infants.

AIM: This study evaluated mothers with diabetes to determine whether prepregnancy body mass index (BMI), BMI on delivery or gestational weight gain (GWG) had the greatest impact on maternal and neonatal outcomes. METHODS: We retrospectively examined the medical charts of 634 full-term infants born to mothers with gestational diabetes mellitus not requiring insulin (n = 476), gestational diabetes mellitus requiring insulin (n = 140) and insulin-dependent diabetes mellitus (n = 18). Data regarding maternal BMI before pregnancy and on delivery were recorded, as well as maternal and neonatal complications. RESULTS: Infants born to women who gained more than the recommended weight during pregnancy had higher birthweights, higher rates of meconium-stained amniotic fluid and neonatal hypoglycaemia. Using logistic regression, Caesarean section delivery was predicted by gestational diabetes requiring insulin, with an odds ratio (OR) of 1.76, maternal hypertension (OR 2.4), infants born large for gestational age (OR 2.78) and maternal BMI ≥ 30 on delivery (OR 1.06). Neonatal complications were predicted by maternal insulin-dependent diabetes (OR 5.21), lower gestational age (OR 0.8) and GWG above the recommended amount (OR 1.56). CONCLUSION: Women with diabetes should be made aware that higher GWG can lead to Caesarean section delivery, infant macrosomia and other neonatal complications.

Bone density among infants of gestational diabetic mothers and macrosomic neonates.

Decreased bone density has been found among infants of diabetic mothers and among large-for-gestational-age newborns. To evaluate which etiologies (physical or metabolic effect) have the greatest impact on neonatal bone density. A case-control study was conducted that included two study groups: one comprising 20 appropriate-for-gestational-age (AGA) infants of gestational diabetic mothers (IGDM) and matched controls, and the other comprising 20 macrosomic infants (birth weight > 4 kg) and matched controls. Bone density was examined along the tibia bone using quantitative ultrasound that measured speed of sound. Bone density among the group of macrosomic infants was significantly lower than among the control group (2,976 vs. 3,120 m/s respectively, p < 0.005). No differences in bone density were found between infants of diabetic mothers and their controls (3,005 vs. 3,043 m/s respectively, p = 0.286). Low bone density was predicted only by birth weight (for every increase of 100 g) (OR 1.148 [CI 1.014-1.299], p = 0.003). Bone density was found to be low among macrosomic newborn infants, whereas among AGA-IGDM infants bone density was similar to that of the control group. These findings strengthen the hypothesis that reduced fetal movements secondary to fetal macrosomia constitute the mechanism for reduced bone density.

Delivery room breastfeeding for prevention of hypoglycaemia in infants of diabetic mothers.

OBJECTIVE: To evaluate the effect of duration of early breastfeeding in the delivery room on blood glucose levels among term neonates of diabetic mothers. METHODS: Mothers with gestational diabetes were encouraged to breastfeed their infants immediately after birth in the delivery room. The breastfeeding duration was recorded by the midwife. RESULTS: The longer duration of breastfeeding subgroup (n = 39) demonstrated a lower rate of hypoglycaemia in the first 8 hours of life (< 40 mg/dl) compared to the shorter duration subgroup (n = 40), but this difference did not reach statistical significance (2.6% vs. 17.5% respectively, p = 0.057). Hypoglycaemia was mainly predicted by lower cord glucose for each decrease of 10 mg/dl (OR 2.11 [CI 1.1-4.03] p = 0.024. CONCLUSION: Longer duration of delivery room breastfeeding did not reduce the rate of hypoglycaemia, which was mainly influenced by lower cord blood glucose level.

The impact of genetic and environmental factors on homocysteine levels in preterm neonates.

BACKGROUND: Hyperhomocysteinemia may be associated with vascular complications in adults. Whereas pediatric thrombosis risk peaks in neonates, data on homocysteine (Hcy) levels assessed in term and preterm infants during the perinatal period are scarce. In the present study, we aimed to establish Hcy reference values for preterm infants and study their potential associations with the early post-natal health status. Plasma Hcy and hematocrit levels and MTHFR polymorphisms (C677T and A1298C substitution) were studied in a large cohort of preterm infants in a tertiary referral medical center during an 18-month period. Data were collected on maternal history and delivery as well as on post-natal complications. RESULTS: The study cohort included 167 infants whose mean gestational age was 30.98 ± 2.34 weeks (range: 26-36 weeks), mean birth weight 1327.6 ± 327 g, and mean Hcy level 7.99 ± 3.27 (range: 2.2-21.2) µmol/L. Maternal intake of folic acid was inversely associated with the babies' Hcy levels (P = 0.0001). Increased Hcy levels positively correlated with birth weight, gestational age (P < 0.005), total number of pregnancies (P = 0.012), and presence of MTHFR polymorphism. Higher Hcy levels were associated with feeding (P = 0.008), especially total parenteral nutrition (P = 0.0001). There was no correlation between Hcy levels and any vascular post-natal complications. CONCLUSIONS: During their post-natal hospitalization, preterm infants may have relatively high, that is, within the adult normal range, Hcy levels which are influenced by genetic and environmental factors. Despite the fact that no correlation was found between Hcy levels and post-natal complications, these associations should be further studied.

Meconium-stained amniotic fluid and the need for paediatrician attendance.

AIM: To determine perinatal parameters among term newborn infants born by vaginal delivery with meconium-stained amniotic fluid (MSAF) that needed paediatrician assistance. METHODS: Paediatricians who were in attendance in the delivery room due to MSAF among term infants completed 775 reports regarding the infants' delivery conditions, and the assistance provided. We defined 'paediatrician attendance needed' for a subgroup of infants for whom we retrospectively determined that paediatrician attendance in the delivery room was required. RESULTS: 'Paediatrician attendance needed' was determined in 31 (4%) cases. Among cases with documented normal foetal monitor, only 10 (1.8%) were defined as 'paediatrician attendance needed', a percentage significantly lower than among infants born following non-reassuring foetal monitor: 21 (9.7%) (p < 0.001). 'Paediatrician attendance needed' was predicted by non-reassuring foetal monitor [OR 6.02 (CI 2.72-13.31), p < 0.001], maternal fever [OR 6.34 (1.92-20.92), p = 0.002] and younger maternal age (for every year) [OR 0.889 (CI 0.82-0.96), p = 0.003]. CONCLUSIONS: Term newborn infants born by vaginal delivery with MSAF with documented normal tracing foetal monitor are at low risk of the need for paediatrician assistance. Paediatrician attendance in the delivery room in labour involving MSAF should be recommended when non-reassuring foetal monitor tracing is observed and should also be considered when maternal fever is recorded, and/or thick meconium is observed.

Short-term outcome among term singleton infants with intrapartum oligohydramnios.

AIM: To evaluate rates of early short-term neonatal complications among term singleton newborn infants with oligohydramnios. METHODS: Retrospective data were collected on 456 term infants with prenatal diagnosis of oligohydramnios and on matched controls, including information on maternal condition and on infant perinatal complications. RESULTS: Infants in the study group were born with lower birthweight and were SGA compared with those in the control group. Rates of renal malformations were significantly higher in the study group compared with the controls (15-3.3% and 3-0.7%, respectively; p = 0.007). Among the severe oligohydramnios subgroup (Amniotic Fluid Index <2), renal anomalies were even more prevalent compared to other infants with oligohydramnios and to the controls (6-9.8%, 9-2.3% and 3-0.7%, respectively; p < 0.001). The incidence of skeletal deformities (developmental dislocation of hip and torticollis) was higher among the study group. CONCLUSION: Term infants with oligohydramnios that was detected near birth are associated with a greater prevalence of renal malformations (mostly mild hydronephrosis) as well as congenital torticollis and developmental dislocated hips compared with controls. Postnatal renal evaluation should be considered in infants with severe oligohydramnios.

Human milk versus formula feeding among preterm infants: short-term outcomes.

We evaluated short-term neonatal outcomes among preterm infants according to type of feeding administered (human milk or formula). Retrospective data were collected on 400 preterm infants at gestational age ≤32 weeks. Groups were chosen and compared according to feeding type. The premature infants who were fed human milk had lower gestational age and birth weight than those who were formula fed. Lower rates of necrotizing enterocolitis (NEC) were detected in the group of infants fed human milk (p = 0.044). Lower rates of retinopathy of prematurity (ROP) were detected in a subgroup of breast-fed infants born at 24 to 28 weeks' gestational age, but the results did not reach statistical significance using univariate analysis (p = 0.06). Using multivariate analysis, however, ROP stage III among this subgroup was significantly lower (p = 0.022). No differences were recorded for other neonatal complications such as infections or for growth parameters. The advantage of human milk feeding, found mainly among preterm infants with respect to rates of NEC and ROP, supports efforts to encourage mothers to feed their infants human milk.

Meconium-stained amniotic fluid and hypoglycemia among term newborn infants.

To evaluate whether meconium-stained amniotic fluid (MSAF) is a risk factor for neonatal hypoglycemia. Retrospective recording of medical charts of full-term infants born following observation of meconium-stained amniotic fluid to examine glucose levels in the first hours of life. Out of 803 infants of the study group, 68 (8.5%) had glucose levels lower than 47 mg/dl. Most (6.7%) had mild hypoglycemia, and 14 (1.8%) had moderate or severe hypoglycemia (1.4% and 0.4% respectively). No infant developed clinical signs clearly related to hypoglycemia. Low-risk infants born following meconium-stained amniotic fluid are not at increased risk for neonatal hypoglycemia.

Exposure to War Prior to Conception: Maternal Emotional Distress Forecasts Sex-Specific Child Behavior Problems.

OBJECTIVES: Exposure to maternal stress during the prenatal period adversely affects child outcomes. Recent investigations have shifted to an even earlier period, the preconception period, to better understand the role of this formative period in human health and disease. We investigated the links between maternal emotional distress following preconception exposure to war, and child outcomes at age 10. MATERIAL AND METHODS: Before becoming pregnant, mothers were exposed to missile bombardment on the north of Israel in the 2006 war. Mothers who conceived within 12 months after the war were recruited and compared to mothers who conceived during the same period but lived in Israel but outside missile range. During the initial assessment, mothers completed a questionnaire on emotional distress. At 10 years of age, mothers and children (N = 68) reported on child socio-emotional outcomes. RESULTS: Multiple regression analyses revealed that, in girls, higher maternal emotional distress following preconception war exposure predicted more internalizing and externalizing behavior problems, and more behavior regulation problems. In boys, maternal emotional distress was not significantly related to outcomes. CONCLUSION: Maternal emotional distress following preconception exposure to war forecasts sex-specific child behavioral problems as reported by the mother and the child. Though the results warrant cautious interpretation because of the relatively small sample size and differential attrition, our findings add to the small but growing body of research on the consequences of maternal stress exposure prior to conception for the next generation.

"I'll Be There": Informal and Formal Support Systems and Mothers' Psychological Distress during NICU Hospitalization.

Mothers of infants hospitalized in the Neonatal Intensive Care Unit (NICU) are at a high risk for psychological distress, which is of concern to health and social professionals due to the negative implications for mothers and infants. A model for explaining maternal psychological distress, consisting of intolerance to uncertainty and support from informal (spouse, family, and friends) and formal (medical staff) systems was examined. Data was collected from one of the largest NICUs in Israel; 129 mothers of 215 preterm infants completed self-report questionnaires regarding their background variables, intolerance to uncertainty, perceived informal support and perceived medical staff support. The NICU's medical staff provided indicators for the infants of participating mothers. A hierarchical multiple regression analysis was conducted. The examined model explained 29.2% of the variance in maternal psychological distress. Intolerance of uncertainty positively predicted psychological distress. Informal support, and in particular, spousal support negatively predicted psychological distress above and beyond intolerance of uncertainty. Medical staff support negatively predicted psychological distress above and beyond intolerance to uncertainty and informal support. Our findings suggest that maternal psychological distress is reduced through a family-centered care approach in NICUs. Medical professionals and social services should develop further solutions for addressing preterm mothers' need for certainty and support.

Excessively high bilirubin and exchange transfusion in very low birth weight infants.

AIM: To evaluate the performance of exchange transfusion in very low birth weight (VLBW) infants with excessively high serum bilirubin levels. METHODS: A population-based observational study using data collected by the Israel National VLBW Infant Database. The study sample comprised 13,499 infants. Two definitions of excessively high-peak bilirubin levels that might be considered as threshold levels for performance of exchange transfusion were used. First, a bilirubin level of ≥15 mg/dL for all infants (PSB-15), and second, incremental bilirubin levels ranging from 12 to 17 mg/dL according to gestational age (PSB-GA). RESULTS: Four hundreds sixty-eight (3.5%) and 1035 infants (7.7%) infants in the PSB-15 and in the PSB-GA groups respectively had peak serum bilirubin levels above thresholds for exchange transfusion. Exchange transfusions were performed in 66 (14.1%) of these infants in the PSB-15 group and 91 (8.8%) in the PSB-GA group. Using logistic regression analysis, peak serum bilirubin was found as an independent factor for performing exchange transfusion. CONCLUSION: Exchange transfusion was performed in only 9-14% of VLBW infants with excessively high bilirubin levels. We speculate that this may be a result of an absence of definitive guidelines or the possible belief that the risks of exchange transfusion outweigh the potential risk of bilirubin-induced neurological injuries.