Infant of a Diabetic MotherReview of Newborn ImplicationsJamie Haushalter, CPNP-PC Newborn NurseryEmily Freeman, CPNP-PC Newborn NurseryErin Burnette, NP-C Newborn Nursery

Purpose and Objectives• Review pathophysiology of diabetes in pregnancy and

implications for the newborn• Apply “Up to Date” Information to practice. • The learner will be able to

• Identify at least 3 neonatal complications associated with being an infant of a diabetic mother.

• Explain the pathophysiology of increased incidence of respiratory distress in the IDM infant.

Types of Diabetes

Preconception Diabetes• Type 1 or Type II Diabetes

• 1.8 percent prevalence• Usually diagnosed if fasting

glucose ≥92 or random glucose ≥200.

• Hgb A1C ≥6.5%

Gestational Diabetes• Diabetes first diagnosed during

pregnancy. • 2-25% prevalence

• Glucose tolerance test btw 24-28wks • 1hr (50g): ≥130 with 99%

sensitivity and 77% specificity• 1hr (50g): ≥140 with 85%

sensitivity and 86% specificity

Gestational Diabetes: Classifications• The White Classification system is used to differentiate

between gestational diabetes and diabetes that existed prior to pregnancy. Gestational diabetes is class A with the following subclassifications:• A1GDM: diet controlled• A2GDM: medication controlled with insulin versus oral anti-

hyperglycemic agents• Insulin is recommended therapy, as oral anti-hyperglycemics are not

approved for treatment of GDM, however they are often used. • Oral anti-hyperglycemic agents that are sometimes used:

• Glyburide: studies have not shown an increased risk of excessive neonatal hypoglycemia with this medication.

• Metformin: Often provides less control of maternal blood sugars than insulin or glyburide.

Maternal Diabetes Results in Fetal Complications….WHY?

• In first trimester, hyperglycemia can lead to SAB or birth defects, more commonly in pregestational diabetes.

• In the 2nd and 3rd trimesters, diabetic ‘fetopathy’ begins to occur.

• Higher levels of glucose and insulin in the mother causes fetal hyperglycemia, hyperinsulinemia, and macrosomia which can lead to neonatal complications.

• Greater risk of birth injuries: shoulder dystocia, clavicle fracture, brachial plexus injury, cephalohematoma, asphyxia

Neonatal Complications• Congenital anomalies• Prematurity• Perinatal asphyxia• Macrosomia• Respiratory distress

• Metabolic abnormalities • Polycythemia• Low iron stores• Hyperbilirubinemia• Cardiomyopathy

“Fetopathy”

Chronic fetal hyperinsulinemia

• Caused by increased metabolic demands

O2 consumption, fetal hypoxemia, erythropoiesis

• Caused by placental insufficiency

Polycythemia- ?HTN and cardiac

hypertrophy

• Fetal Complication- still birth

Neonatal Complications• Congenital Anomalies

• Heart malformations are present in 3-9% of diabetic pregnancies• Most common heart defects seen in

infants of diabetic mothers:• Transposition of the great arteries• Double outlet right ventricle• Ventricular septal defect• Truncus arteriosus• Tricuspid atresia• Patent ductus arteriosus

• Neural tube defects, intestinal complications, and orthopedic anomalies also more common.

• Risk of anomalies reduced by tight maternal glycemic control

• Prematurity• Due to both medically indicated

and spontaneous deliveries.• Women with diabetes are more

at risk for delivering early, however mechanism is unclear.

• May be related to preeclampsia, developing macrocomia, nephropathy, poor glycemia control, and risk of late fetal death.

Neonatal Complications• Perinatal Asphyxia

• Increased metabolic rate, leading to increased oxygen consumption and fetal hypoxemia, as placenta cannot keep up with demands.

• Macrocomia can make delivery difficult, increased risk of shoulder dystocia.

• Cardiomyopathy leading to abnormalities in fetal heart rate.

• Macrosomia• Maternal elevated sugars cause

increased growth of the fetus, especially in insulin sensitive tissues (SQ fat, cardiac muscle, liver).

• Elevated insulin levels in the fetus stimulates glycogen storage in the liver, increased lipid synthesis, and accumulation of fat.

• Infants have bigger head:chest and shoulder:head ratios, more body fat, and visceromegaly.

• Disproportionate macrosomia increases the risk of hyperbilirubinemia, hypoglycemia, metabolic acidosis, and respiratory distress.

Neonatal Complications• Respiratory Distress

• Common complication in infants born to diabetic mothers because maternal hyperglycemia delays surfactant synthesis and can lead to impaired or delayed lung maturation.

• Increased risk of neonatal respiratory distress syndrome

• 2-3 times more likely to have Transient Tachypnea of the Newborn (TTN)• Hypothesized to be caused by delayed

fluid clearance in the diabetic fetal lung• C-sections more common in this

population which also increases risk of TTN

• Metabolic Abnormalities• Hypoglycemia

• Defined as BG <40, onset usually within the first few hours of birth

• Commonly occurs in macrosomic infants because of continued hyperinsulinemia even after being removed from their intrauterine glucose supply, even 2-4 days.

• Strict maternal glucose control can reduce the risk but does not eliminate the possibility of hypoglycemia in the newborn.

• SGA infants also at risk because of decreased glycogen stores and hyperinsulinemia decreases the ability to mobilize hepatic glycogen.

Neonatal Complications: Metabolic Abnormalities• Hypocalcemia

• Serum Ca <7mg/dL• Occurs in 5-30% in IDMs• Good maternal glycemic control

reduces risk• Infants usually asymptomatic and

resolves without treatment, therefore routine screening not recommended.

• Consider measuring in symptomatic infants: jittery, apnea, tachypnea, lethargy, seizures.

• Hypomagnesemia• Serum Mg level <1.5/dL• 40% of IDMs within the first 3

days after birth. • Thought to be due to low

maternal levels from urinary loss secondary to diabetes.

• Usually transient and asymptomatic therefore no need to screen unless clinical concern.

Neonatal Complications• Polycythemia

• Increased erythropoietin concentrations caused by chronic fetal hypoxemia

• Polycythemia can lead to hyperviscosity syndrome and vascular sludging (if severe can cause ischemia and infarction or organs)

• Check hematocrit within 12 hours of birth

• One study showed 17% on IDMs had Hcts> 60 and 5% >65

• Low iron stores• Inversely related to degree of

polycythemia. • With hypoxemia, fetus has increased

red cell mass, which causes iron redistribution, leading to iron deficiency in developing fetal organs cardiomyopathy, neurodevelopmental problems, etc.

• As extra red cells are eventually broken down, the iron will be recirculated, so supplementation is not necessary.

Neonatal Complications• Hyperbilirubinemia

• 11-29% of IDMs• Associated with prematurity,

poor maternal glycemic control, macrosomia and polycythemia

• Cardiomyopathy• Increased risk of transient

cardiomyopathy thought to be caused by fetal hyperinsulinemia increasing the synthesis and deposition of fat and glycogen in myocardial cells.

• Decreases size of ventricles, possibly obstructing outflow of the left ventricle.

• Infants with cardiomyopathy are often asymptomatic, however 5-10% will have respiratory distress or signs of poor cardiac output.

• Congestive cardiomyopathy rare.

Management of the Infant of a Diabetic Mother

• Lab testing for hypoglycemia and polycythemia.• Glucose monitoring within 1-2 hours after birth and with symptoms.

Should be preprandial and continue for the first 12-24 hours of life. • Check hematocrit 12 hours after birth.

• Assess for cardiac and respiratory disease if cyanosis present.• Monitor for jaundice• If symptomatic, consider calcium and magnesium levels.

Outcomes• Genetic susceptibility for development of diabetes, especially if

mother has type 1. • 2% risk if mom has type 1 diabetes versus 0.4% if mother did not have diabetes. • With type 2 diabetes, a first degree relative has a 5-10x higher chance of

developing T2DM.

• Risk for increased BMI, obesity, and impaired glucose metabolism due to intrauterine exposure to hyperglycemia and fetal hyperinsulinemia.

• If maternal diabetes is poorly controlled, risk of developmental abnormalities in the infant, especially if head circumference was small or if mother had higher ketone levels in the 2nd and 3rd trimesters.

Thank you for caring for our “cupcake” babies!

References

http://www.uptodate.com/contents/infant-of-a-diabetic-mother

http://www.uptodate.com/contents/screening-and-diagnosis-of-diabetes-mellitus-during-pregnancy?source=see_link

Thank you!