Diabetes in Pregnancy

Dr. Ab Rahim B Abd Ghani

HPSF MUAR

Overview

1. Introduction

2. Definition

3. Screening

4. Management

5. Complications/Outcomes

Introduction• Diabetes in pregnant women is associated

with an increased risk for maternal and neonatal morbidities and remains a significant medical challenge.

• 650,000 births in England & Wales per year

• 2-5% women have diabetes

• 87% diabetic pregnancies due to gestational diabetes

Introduction• Prevalence diabetes is increasing

• Early diagnosis of gestational diabetes is an important step to improve outcomes and systematic or selective screening with the OGTT should be established

• Perinatal mortality remains 5x higher

• Congenital malformations up to 10x more common

Diabetes in Pregnancy

• Gestational Diabetes Mellitus (88%)

• Type 1 Diabetes Mellitus (4%)

• Type 2 Diabetes Mellitus (8%)

Definition

• ‘carbohydrate intolerance resulting in hyperglycemia of variable severity with onset or first recognition during pregnancy’

World health Organization, 1999

Statistics- Prevalence of GDM in Malaysia

•N Idris et al -prevalence of GDM –18.3%

•Peng Chiong Tan, prevalence of GDM -11.4%

•Nurain et al, prevalence of GDM – 16.1%

SCREENING

• Controversial• Aim – early diagnosis is important to improve

outcomes• Universal screening is recommended, but currently

using selective screening base on risk factors• Would vary according to

– Population – (eg:asians>whites)– Timing– (high risk?average risk?low risk?)– Screening tests-50 g – Criteria used for diagnosis- WHO, ADA

Screening-Suggested (NICE guideline 2008)

• Screening for gestational diabetes using risk factors at the booking appointment

• Early self-monitoring of blood glucose or a 2-hour 75 g oral glucose tolerance test (OGTT) at 16–18 weeks to test for gestational diabetes if the woman has had gestational diabetes previously.

• Followed by OGTT at 28 weeks if the first test is normal

• An OGTT to test for gestational diabetes at 24–28 weeks if the woman has any other risk factors.

Who should be screened

Clinical characteristics including• Obesity• Symptoms (polyuria, polydipsia)• Personal history• Glucosuria• Family history• Previous big baby• Polyhydramnios• Previous unexplained stillbirths/neonatal death• History of recurrent vaginal candidiasis

Detecting diabetesWorld Health Organization

American Diabetic Associationetc

Overt Diabetes

GDMusing 75 g OGTT

The MGTT• 75 g Load of glucose in flavoured drink

given

• Fasting levels < 5.6 mmol/L

• Post drink 2 hours < 7.8 mmol/L

Blood Sugar Profile- WHO

Pre or Post Prandial

Blood Sugar Profile- Suggested Timing and Values

Pre breakfast/Fasting

6

2 hrs post Breakfast

7

2 hrs post Lunch 7

2 hrs post Dinner 7

FETAL & PERINATAL COMPLICATIONS

Embryo Fetus Newborn

Abortions Malformations

Growth alterations macrosomia

IUGR

Dystocia

Perinatal asphyxia

Metabolic alterationsHypoglycaemiaHypocalcaemia

HyperbilirubinemiaPolycythaemia

Alterations of lung maturity

Respiratory distress syndrome

Sudden Intrauterine

demise

MATERNAL COMPLICATIONS

Hypertension

Preterm labor

InfectionsUrinaryVaginal

VascularRetinaRenal

Cardiac

Hyper/hypoglycaemiaAcidosisComa

Polyhydramnios

Increased operative delivery and birth trauma

Management

• Pre pregnancy Counseling

• Antenatal

• Intrapartum

• Postpartum

Pre pregnancy CounselingGeneral guidelines:•Pregnancy is planned, •Explain risks of congenital anomalies and spontaneous abortions – depends on glucose control•Information on chronic complications and potential impact on pregnancy and effect of pregnancy on chronic complications•Fitness for pregnancy –retinopathy, nephropathy, HPT, neuropathy and IHD

Pre pregnancy counseling

• Physical examination –BP, eye examination, renal status, cardiac status, neurological assessment

• Laboratory evaluation –HbA1c, renal function, 24h urine creatinine clearance, protein, Urine C&S

• Optimize Glycaemic control- Combine care/dietitian. Against preg if HbA1c >10

• Start on Folic acid 5mg od.

Antenatal ManagementBefore or as soon as pregnancy is confirmed:• Stop oral hypoglycaemic agents, apart from

metformin, and commence insulin if required• Stop angiotensin-converting enzyme inhibitors

and angiotensin-II receptor antagonists and consider alternative antihypertensives

• Stop statins.

Antenatal Management

• Dating Ultra sound first trimester

• Refer to Booking to Hospital with specialist

• Refer to Dietitian

• Consider Starting Insulin if target blood glucose not achieve after 1-2 weeks on diet.

• Screen for Diabetic Retinopathy and Nephropathy especially established Diab early or at 28 weeks

Antenatal Management

• Antenatal examination of the four-chamber view of the fetal heart and outflow tracts at 18–20 weeks

• Ultrasound monitoring of fetal growth and amniotic fluid volume every 4 weeks from 28 to 36 weeks

• individualised monitoring of fetal wellbeing to women at risk of intrauterine growth restriction (those with macrovascular disease or nephropathy).

Antenatal Management

• Not to allow post date in GDM on diet control

• Deliver at 38 weeks if on Insulin Therapy

• To discuss mode and timing of delivery based on assessment of glycaemic control, insulin dosing and estimation of fetal weight.

Outcomes of a diabetic pregnancy to the fetus

EARLY PREGNANCY

• If glycemic control poor within first 8 weeks/ HbA1c >9.5% there is an increased risk of spontaneous miscarriages and major malformations

• Target Hb A1c 6.1%

Congenital malformations• High maternal

glucose is toxic to the early embryo – Risk rises with worsening glycaemic control at conception and in early first trimester

• Esp renal, cardiac and central nervous system abnormalities

Caudal regression syndrome (sacral agenesis)

• The overall incidence: 1 in 7,500 live births. • About 1 in 6 of patients is the child of a diabetic mother. • The risk for a child of a diabetic mother of acquiring the

syndrome is 1%.

LATER IN THE PREGNANCY

• Incidence of abnormal fetal heart rate, low Apgar scores is increased

• Higher risk of fetal asphyxia and distress

• Higher risk of stillbirths (d/t the chronic fetal hypoxia)

Fetal macrosomia• Hallmark of diabetic pregnancy

• High placental transfer of glucose leads to hyperplasia of foetal pancreas and foetal hyperinsulinaemia

• Insulin is the main growth hormone for the foetus – hence macrosomia

• Brain growth is spared

• AC measured serially is the best measurement for macrosomic fetuses

• Much of the excess weight is truncal fat, hence shoulder dystocia

• Macrosomia occurs in 25% of infants of type 1 diabetic mothers

• Excessive insulin secretion persists after birth, hypoglycaemia

• Hyperglycaemia is the main causative factor in delayed lung maturation

Shoulder Dystocia with brachial plexus injury

9% when BW < 4 kg

26% when BW > 4.5kg

5-10% of infants have permanent brachial plexus injuries.

Consider delivery by LSCS if suspected fetal Macrosomia

Most likely due to poor Glycemic control especially post pandial.

Hypoglycemia

• Most common cause of neonatal morbidity in infants of diabetic mothers

• Maternal control during pregnancy and labour and delivery will influence the degree of hypoglycemia

• Neonatal hypoglycemia is usually asymptomatic• Routine blood sugar monitoring is recommended• A level of 2.6 mmol/L or above is generally

accepted

Established Diabetes1 – 2% of the pregnant population.Higher risk for Maternal complication with high

perinatal morbidity and mortality.Effects of pregnancy of DM• Insulin requirements increases during pregnancy• Retinopathy aggravated• Those with nephropathy more likely to have pre

eclampsia• High risk of preterm delivery and asymmetrical

SGA• Combine care important.

Summary of ManagementPre Pregnancy Planning necessary for good control

Switch from OHA to insulin

Women should be taught to monitor their own glucose levels

HbA1c should be checked at booking

Pregnancy Aim to maintain normoglycemia

Antenatal follow ups should monitor blood pressure, look for s/s of infection, fetal growth monitored by clinical means as well as ultrasound

Delivery Aim for spontaneous delivery however usually induction done at 38 weeks. If on diet control at EDD.

IV insulin and IV glucose (DIK) regime during labour

Beware of shoulder dystocia

Management

• Key to successful management is early diagnosis• Early treatment• Maintain good Glycemic control• Early ultrasounds to exclude fetal abnormalities• Attempt diet control (unless patient already

established diabetic)• Followed by insulin if not controlled by diet• Oral hypoglycemics should be avoided as risk of

teratogenicity in early pregnancy unless poorly control despite high dose insulin.

Medication

• Metformin may be used before and during pregnancy, Reserve for poorly control on high dose insulin.

• Data from clinical trials and other sources do not suggest that the rapid-acting insulin analogues (aspart and lispro) adversely affect pregnancy or the health of the fetus or newborn baby.

• Evidence about the use of long-acting insulin analogues during pregnancy is limited. Isophane insulin is the first-choice long-acting insulin during pregnancy.

Delivery• Timing of delivery depends on control• If on insulin, the pregnancy is best terminated by 38 weeks• If diet control is adequate then the pregnancy may be

prolonged to term• Mode of delivery depends on clinical judgement• Diabetes itself is not an indication for caesarean• Factors favoring an elective CS are

– Macrosomia– Suspicion of cephalopelvic disproportion– Malpresentation– polyhydramnious

During Labour:

• DIK regime used

• Infusion of 500ml of 10% Dextrose with 1 g KCL to which an appropriate dose of insulin added.

• Dose of insulin should be titrated accordingly to hourly GM

• Adequate pain relief

• Continuous CTG

• Trained birth attendant

Postpartum

• Monitor for hypoglycemia/hyperglycemia• Requirement of insulin halved post partum• Consider restart back on OHA once taking normal

diet• Advice breast feeding• Schedule appointment for review of diabetes and

repeat MOGTT at 6/52• Contraception advice, Life style modification

References• World Health Organization Prevention of diabetes

mellitus. Geneva, World Health Org., 1994 . • American Diabetic Association• Australasian Diabetes in Pregnancy Society.

http://www.adips.org/• Malaysian Clinical practice guidelines for management of

Type II Diabetes Mellitus. 4th Edition. 2009• Diabetes in Pregnancy. NICE. March 2008

THANK YOU