Neurobehavioural Outcomes in Late Preterm Neonates
Neurobehavioural Outcomes in Late Preterm Neonates
Hypertensive disorders are the most common medical complications in pregnancy and major
 causes of maternal, fetal, and neonatal morbidity and mortality. Fifty percent of
 hypertensive disorders of pregnancy are defined as pre eclampsia, the most important
 manifestation of the disease.

 Preeclampsia is also a significant risk factor in the development of IUGR and represents the
 most common cause of IUGR in the nonanomalous infant. The incidence of thrombocytopenia,
 neutropenia and Bronchopulmonary dysplasia is also increased in neonates with preeclampsia.

 The neurodevelopmental outcomes infants exposed to preeclampsia are highly variable. The
 study by Gray et al showed that preeclampsia is associated with a decreased risk of cerebral
 palsy. They also found a protective effect of maternal preeclampsia on cerebral palsy
 regardless of exposure to magnesium sulfate. However, contrary to this, study conducted by
 Shao-Wen Cheng et al has showed that infants born to pre-eclamptic mothers had lower MDI
 scores at 24 months of age (P= 0.04) as compared to infants without maternal pre-eclampsia.
 The study by Szymonowicz et al showed that neonates born to pre-eclamptic mothers had a
 significantly lower mean mental developmental index, and significantly more of these children
 had one or more impairments compared with the control group at 2 years of age. The
 neurodevelopmental outcomes in neonates born to preeclamptic mothers therefore remain
 inconclusive. Recently the role of neurobehaviour being evaluated early at 37-40 weeks of CGA
 is being predicted as an useful adjunct to the 12-18 month full neurodevelopmental
 assessment. This assumes significance in the context of initiation of early stimulation and
 objectivised individual developmental rehabilitation regimens for these infants.
Preeclampsia is a multiorgan, heterogeneous disorder of pregnancy associated with significant
 maternal and neonatal morbidity and mortality.

 The incidence of preeclampsia is about 5% to 10% of all pregnancies, with higher rates
 reported in first pregnancies, twin pregnancies, and in women who have had previous pre
 eclampsia. Fifty percent of hypertensive disorders of pregnancy are defined as preeclampsia,
 the most important manifestation of the disease.

 While preeclampsia complicates 6%-10% of all pregnancies in the United States, the incidence
 is believed to be even higher in underdeveloped countries.

 Perinatal mortality rates from range from 59 in 1,000 in developed countries to more than 300
 in 1,000 in low income countries.

 Preeclampsia and eclampsia accounts for 24% of all maternal deaths in india. Diagnostic
 criteria for preeclampsia Blood pressure Greater than or equal to 140 mm hg systolic or
 greater than or equal to 90 mm hg diastolic on two occasions at least 4 hours apart after 20
 weeks of gestation in a woman with previously normal blood pressure Greater than or equal to
 160 mm hg systolic or greater than or equal to 110 mm hg diastolic , hypertension can be
 confirmed within a short interval ( minutes ) to facilitate timely antihypertensive therapy
 And Proteinuria Greater than or equal to 300 mg per 24 hour urine collection ( or this amount
 extrapolated from a timed collection ) or Protein / creatinine ratio greater than or equal to
 0.3 mg/dl Dipstick reading of 1+( used only if other quantitative methods not available )

 Or in the absence of proteinuria, new onset hypertension with the new onset of any of the
 following:

 Thrombocytopenia Platelet count less than 100000/ microliter Renal insufficiency Serum
 creatinine concentrations greater than 1.1 mg/dl or a doubling of the serum creatinine
 concentration in the absence of other renal disease Impaired liver function Elevated blood
 concentrations of liver transaminases to twice normal concentration Pulmonary edema Cerebral
 or visual symptoms

 LATE PRETERMS: A SPECIAL COHORT

 Definition:

 Premature infants ( born at < 37 completed weeks gestation) are categorized into subgroups

 -  Very preterm (<32 completed weeks)

 -  Moderately preterm (between 32 and 33 completed weeks)

 -  Late preterm (between 34 and 36 completed weeks) Late preterm birth is an accepted term
 used for infants born at 34 0/7 to 36 +6/7 weeks gestation. This group was initially
 referred to as near term, but misleading implications of maturity has prompted the name
 change to late preterm.

 Magnitude of late preterm births Prematurity is a leading cause of morbidity and mortality
 globally. Advances in medicine and technology have shifted the distribution of births away
 from term/post-term towards earlier gestations.

 The percentage of live births in the United States that were born late preterm increased
 between 1990 and 2006 from 7.3% to 9.14% , a 25% increase.

 This increase accounted for 84% of the increase in the prematurity during that same 16 year
 period. Thus this group of late preterms account for the maximum burden of premature births.

 Etiology of late preterm births Preterm deliveries are divided into two groups

 -  The first group: Spontaneous late preterm births (premature labor with intact membranes
 or premature rupture of membranes) where there is limited control on preventing the
 birth and the focus lies in a better understanding of the management of the neonate in
 the perinatal period.

 -  The second group includes premature babies born after the induction of labor or
 performance of a cesarean section for maternal or fetal indications.

 Consequences of late preterm births Acute Medical Morbidities and Mortality

 This group is characterized by physiological immaturity with limited compensatory responses
 to extrauterine environment compared to term infants. They have greater risk than term babies
 for morbidities and mortalities such as:

 -  Temperature instability

 -  Hypoglycemia

 -  Respiratory distress

 -  Apnea

 -  Jaundice

 -  Feeding difficulties

 -  Dehydration

 -  Suspected sepsis

 -  Neurologic disorder and/or death The risk of death and/or a severe neurologic disorder
 defined by ischemic encephalopathy,Grade 3 or 4 IVH, cystic periventricular leukomalacia
 and/or seizures increased to 1.7% at 34 Weeks gestation as compared to 0.15% at 38 weeks
 gestation.

 Long-term morbidities in late preterms Long-term outcomes affected by late preterm involve
 school performance, behaviour problems, social and medical disabilities, and mortality.
 Although the absolute risk of poor long-term outcomes in infants born late preterm are small,
 the risks are significantly greater than if born at 39-40 week gestation.Medical and social
 morbidities increase with decreasing gestational age. In cohort of 903,402 Norwegian infants
 born alive without congenital anomalies and followed through early adulthood, infants born
 late preterm had significant higher risks for cerebral palsy; cognitive dysfunction;
 schizophrenia; disorders of psychological development, behavior, and other major
 disabilities.

 EFFECTS OF PREECLAMPSIA ON LATE-PRETERM INFANT OUTCOMES Risk of Fetal Demise/Stillbirth
 Severe preeclampsia represents significant risk factor for intrauterine fetal demise, with
 estimated stillbirth rate of 21 per 1000 20. In the setting of severe preeclampsia, the risk
 of fetal death outweighs the potential benefits of pregnancy prolongation. However, in cases
 of mild preeclampsia, the risk of fetal demise is over 50% less than pregnancies with severe
 preeclampsia (stillbirth rate of 9 per 1000) Intrauterine Growth Restriction (IUGR)
 Preeclampsia, a condition characterized by decreased uteroplacental blood flow and ischemia,
 is a significant risk factor in the development of IUGR and represents the most common cause
 of IUGR in the nonanomalous infant.

 Hematologic Effects Maternal preeclampsia can result in neonatal thrombocytopenia, typically
 defined as a platelet count less than 150,000/uL. Severity of thrombocytopenia related to
 preeclampsia is highly variable, with a small percentage of infants developing severe or
 clinically significant thrombocytopenia (<50,000/uL). In addition to the well-described
 effects of preeclampsia on platelets, neonates delivered to women with preeclampsia have a
 50% incidence of neutropenia (defined as absolute neutrophil count less than 500).

 Bronchopulmonary Dysplasia (BPD) The study by Hansen et al shows that maternal preeclampsia
 is, associated with an increased risk for development of BPD, even after adjusting for
 gestational age, birth weight, and other clinical confounders (OR 2.96, 95% CI 1.17-7.51)
INCLUSION CRITERIA

 -  Late preterm infants

 -  Pre eclampsia in mothers

 -  Parental Consent

 EXCLUSION CRITERIA

 -  Major congenital malformation

 -  Eclampsia ( seizures in mother)

 -  Mothers on antipsychotic drugs

 -  Clinical Chorioamnionitis ( fever > 100.4º F, uterine fundal tenderness, maternal
 tachycardia (>100/min), fetal tachycardia (>160/min) and purulent or foul amniotic
 fluid )

 -  Birth Asphyxia (Apgar score of less than 7 at 1 minute of age)

 -  Multiple gestation.