DIABETES IN PREGNANCY

DR. SALWA NEYAZI

CONSULTANT OBSTETRICIAN GYNECOLOGIST

PEDIATRIC & ADOLESCENT GYNECOLOGIST

PHYSIOLOGICAL CHANGES OF GLUCOSE METABOLISM IN PREGNANCY

Pregnancy is a state of insulin resistance & relative glucose intolerance

This is due to placental production of anti-insulin hormones : hPL, cotisol, and glucagon

FBS Postprandial glucose ↑ ↑ Insulin production ↑ ↑ 2 folds in N women Insulin requirements ↑ ↑ in diabetic women renal threshold for glucose glycosuria

DIAGNOSIS OF GESTATIONAL DIABETES MELLITUS

Women in whom the criteria of DM are met in pregnancy include a gp of diabetics who were undiagnosed before pregnancy

FBS > 7 mmol/L on 2 occasions Or RBS > 11.1 mmol/L on 2 occasions Borderline cases GTT DM is Dx if FBS

> 7 mmol/L or 2 hrs > 11.1 mmol/L Impaired glucose tolerance 2hrs G 8-11

mmol/L with a N FBS

EFFECT OF PREGNANCY ON DM

Insulin requirement ↑ ↑ in pregnancy reaching a max at term & being at least 2 X the pre-pregnancy requirement

Pt with diabetic nephropathy deterioration in renal function with in creatinine clearance & proteinuria

this deterioration in renal function is usually reversed after delivery

EFFECT OF PREGNANCY ON DM

2 X ↑↑ in retinopathy

rapid improvement in glycemic control worsening retinopathy due to ↑↑ retinal blood flow

↑↑ icidence of hypoglycemia

Ketoacidosis is rare unless associated with hyperemesis, infections, tocolytic & corticosteroid Rx

EFFECTS OF DM ON PREGNANCY

↑↑ incidence of congenital abnormalities The risk is related to the degree of glycemic

control 5% with Hb A1c > 8%

25% with Hb A1c > 10% with ↑↑ risk

of abortions Sacral agenesis, congenital heart defects,

skeletal abnormalities & neural tube defects Perinatal & neonatal mortality ↑↑ 2-4 X Unexplained IUFD at term / more in

macrosomic babies

EFFECTS OF DM ON PREGNANCY

Macrosomia the incidence is ↑↑ with poor diabetic control

not eliminated by tight control

associated with ↑↑ risk of operative delivery, birth trauma, & shoulder dystocia

Hyperglycemia fetal polyuria polyhydramnios PROM, preterm delivery

Prematurity pose an added problem as pulmonary surfactant production is slightly delayed in babies of diabetic mothers

EFFECTS OF DM ON PREGNANCY

Postnatally, babies are at risk of hypoglycemia & jaundice

↑↑ risk of PET especially in pt with pre-existing hypertension & nephropathy where it reaches almost 30%

MANAGEMENT

Multidisciplinary team including obstetricians, endocrinologists, dieticians, & midwives optimize outcome

Preconception councelling To achieve normoglycemia as far as possible FBS < 5 mmol/L PP < 7.5 mmol/L Dietary advice on a low sugar, low fat, high fiber

diet Regular capillary glucose series (7 point profile) Combined short acting & intermediate acting

insulin

MANAGEMENT

Regular assessment of Hb A1c Ophthalmologic examination & Rx of

retinopathy Regular monitoring of renal function in Pt with

diabetic nephropathy Detailed U/S screening for congenital

malformations in the 2nd trimester (20wk) to exclude NTD, sacral agenesis, & cardiac defects

Frequency of antenatal visits needs to be individualized

ANTENATAL FETAL SURVELANCE

↑↑ incidence of IUFD justify close monitoring in the 3rd trimester

Serial U/S biometry to detect macrosomia, hydramnios, IUGR

Umbilical artery doppler in Pt with IUGR CTG BPP

LABOR & DELIVERY

With well controlled DM with appropriately grown fetus pregnancy is allowed to proceed till term

When there is concern about fetal well being or macrosomia the risk of IUFD must be weighed against the risk of RDS

½ of the babies are >90th centile CS rate of 50-60%

Intrapartum care should focus on meticulous diabetic control & continuous electronic fetal monitoring . Blood glucose should be 4-7 mmol/L achieved by 5% Dextrose infusion & insulin infusion

LABOR & DELIVERY

After delivery mternal insulin requirement rapidly returns to the pre-pregnancy level

If abnormal glucose tolerance was 1st Dx in pregnancy GTT should be done 6 wk post-partum

Gestational diabetes

Carbohydrate intolerance of variable severity 1st Dx in pregnancy will include women with undiagnosed DM

There is no consensus on the optimal screening for GDM

Universal screeningScreening pt > 25 YClinical risk factors: previous GDM, family Hx ,

previous macrosomic baby, previous unexplained IUFD, obesity, glycosuria, polyhdramnios, LGA in current pregnancy

The timing of screening also contraversal

Implications of GDM

↑ perinatal mortality & morbidity but to a lesser extent than DM

No ↑ risk of congenital malformations Macrosomia is the main risk factor for adverse

outcome ↑ risk of operative deliveries ↑ incidence of PET Women with GDM have a significantly ↑ risk of

DM later in life (50% over 10-15 Y)

Management

Combined diabetic obstetric approach Initial approach by dietery modification including

caloric reduction in obese Pt The need for insulin is manifested by persistent

PP hyperglycemia (7.5-8 mmol/l) or persistant fasting hyperglycemia (>5.5-6 mmol/L)

Regular U/S scans to assess fetal growth & well being

Early delivery is not advised unless there is a complicating factor

Management

Intrapartum management

Depends on whether the pt is on diet control alone or on insulin

Pt on insulin need to be on sliding scale

Following delivery insulin must be discontinued GTT should be done 6 wks postpartum

MACROSOMIA

Fetal Wt >4000-4500 gm regardless of gestational age

Risks of macrosomia include shoulder dystocia, erb’s palsy, 5 min APGAR score, admission to NICU & obesity later in life

Risk factors for the development of macrosomia:

prior HX of macrosomia

↑ maternal pre-pregnancy Wt

excessive Wt gain in pregnancy

multiparity

MACROSOMIA (risk factors)

male fetus

gestational age >40wks

race

maternal birth Wt

maternal Ht

maternal age

+ve GCT with-ve GTT

GD, DM

MACROSOMIA

How macrosomic infants of diabetic mothers differ from those without diabetes?

How is macrosomia predicted? How does it affect the management of labor &

delivery? When is CS recommended for macrosomia? What is the role of induction of labor?