Diabetes complicating pregnancy

Types

1.     Pre existing

Type 1

Type 2

2.     Gestatinal Diabetes Mellitus

Incidence

Preexisting I in 250

GDM 4- 5 %

Preexisting diabetes

Maternal risk

·        Recurrent hypoglycemia

·        Worsening of retinopathy/nephropathy/neuropathy

·        Diabetic keto acidosis

·        Preeclamsia – 2 to 4 times higher risk

·        Increase risk of infection eg vaginal candidiasis, UTI, endometrial or wound infection

·        Increase LSCS rate

Fetal

Congenital anomalies – increased risk of multiple abnormalities with increasing level of maternal hyperglycemia.Main defects are Neural tube and cardiac defects.

Perinatal mortality (excluding congenital abnormality ) 2 fold increased

Pathological fetal growth FGR (IUGR) is common among longstanding DM with microvasular disease Macrosomia – it is the most common among all DM .Due to glucose transfer to fetus causing hyperinsulinemia

Still birth – cause – multifactorial

                        Hypoxia, acidosis , hypokalemia ,placental dysfunction

Shoulder dystocia

Neonatal complication

         Hypoglycemia

         Hypocalcemia

         Polycythemia and hyperviscosity

         Hyperbilurubinimia

         Hypertropic Cardiomyopathy

         Hypomagnesemia

         Pretem bith

         Complication of shoulder dystocia – bone fracture,ERb`s palsy

         Respiratory distress syndrome

 These babies are at risk of adolescent obesity and metabolic syndrome.

Management

Pre pregnancy

1.Lifestyle modification – diet control

                                           Weight reduction

2. Strict diabetic control –  Maintain HBA1C level below 6

3. Contraceptive advice until optimal blood sugar control is achieved

4. Drugs – omit terotogenic hypoglycemic agent , statin and ACEI

5. Baseline renal and retinal assessment and regular follow up

If necessary, proliferative retinopathy may be treated with photocoagulation prior to conception.

6. Manegemt  by joint multidisplinary team

7. folic acid supplements (5 mg/day)

8. Blood glucose meter for self-monitoring

 9. Ketone testing strips to women with type 1 diabetes and advise on use if hyperglycaemic or unwell

Diet

·        Low-carbohydrate diet , high fibre with caloric restriction

·        Frequent small snacks may be needed between meals

·        Avoid starvation

Antenatal management

Retinal assessment

If baseline retinopathy normal repeat at 28 weeks

If background or mild retinopathy repeat at 16- 20 weeks

If severe form identified photocoagulation

Diabetic nephropathy

Early consultation with nephrologist is indicated if serum creatinine is above 120umol/L or urinry protein exceed 2g/d

Screening for congenital abnormalities

All women should be offered 1^st trimester screening for down syndrome

Anomaly scan is routinely offerd at 18 – 21 weeks .

Monitoring fetal growth and well being

Fetal growth is assed on a 4 weekly basis from 28 to 36 weeks gestation.

Fetal well being

·        FHR

·        BPP

·        Umbilial artery Doppler velocimetry

Control of blood sugar

Metformin (and Glibenclamide) may be used before and during pregnancy, as well as insulin

Advise women to test fasting and 1-hour postprandial blood glucose levels after every meal during pregnancy.(BSS)

 Agree individualized targets for self-monitoring.

 Advise women to aim for fasting blood glucose of between 3.5 and 5.9 mmol/litre and 1-hour and postprandial blood glucose below 7.8 mmol/litre.

 The presence of diabetic retinopathy should not prevent rapid optimisation of glycaemic control in women with a high HbA1c in early pregnancy.

 Do not use HbA1c routinely in the second and third trimesters.

                                                                                      

Labour and delivery

Consider delivery after 37 completed weeks

MOD

If no other obstetric indication and EFW < 4.5-  vaginal delivery is possible

If EFW > 4.5 kg – may need LSCS

Maintain plasma glucose in physiological range (4-7mmool/L)during labour and LSCS.

Use intravenous dextrose insulin regime during labour to maintain blood sugar

Dextrose insulin regime

Nil by mouth until after the birth

IV dextrose 10% - 100ml/hr

Hourly blood glucose monitoring

If initial blood glucose 4- 7 mmool/L start insulin 1u/hr

                                        >4mmol/L start 2 u /hr

Adjust insulin dose according to blood glucose level and maintain in-between 4- 7 mmol/L.

                                          If <4 mmol/L decrease by 1 u/hr

                                           If >7mmol/L increase by 0.5u/hr

After delivery halve the infusion rate and Omit 30 after self administration of 1^st dose of subcutaneous insulin.

Postnatal management

Breast feeding can increase the risk for hypoglycemia.

Type 1 DM – start prepregnancy insulin dose and monitor blood sugar and adjust.

Type 2 DM –start pre pregnancy drugs and monitor.

GDM- stop treatment and    Monitor blood sugar

            if high manage it as pre existing DM   and refer to DM clinic   

            If normal discharge and check FBS at 6 weeks

Advice on discharge for a patient with GDM

Risk of DM in later life(life time risk 40%)

Lifestyle modification – diet ,weight reduction

Annual FBS

Risk increased during next pregnancy

Do OGTT before next pregnancy

Gestational diabetes mellitus

Any degree of glucose intolerance with onset or 1st recognition during pregnancy whose intolerance   will return to normal after pregnancy and previously undiagnosed diabetes.

Risk factors for GDM

·        Bodymass index >30kg/m

·        GDM in previous pregnancy

·        Age >25yr

·        Family history of diabetes

·        Ethnicity – non white, Asian

·        Previous delivery of large aby

·        Previous stillbirth

Screening for GDM

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 and 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.

Diagnosis of GDM

Organisation	Fasting Plasma glucose	Glucose Challenge	1-h plasma glucose	2-h plasma glucose	3-h plasma glucose
WHO *	≥ 7.0	75g OGTT	Not required	≥ 7.8	Not required
American Congress of Obstetricians and Gynecologists**	≥5.3	100g OGTT	≥10.0	≥8.6	≥7.8
Canadian Diabetes Association***	≥5.3	75g OGTT	≥10.6	≥8.9	Not required
IADPSG19****	≥5.1	75g OGTT	≥10.0	≥8.5	Not required

*One value is sufficient for diagnosis

** Two or more values are required for diagnosis

*** Two or more values required for diagnosis

**** One value is sufficient for diagnosis

When diabetes is developed during pregnancy, woman is out of long-term risks such as retinopathy, nephropathy and fetus is out of risk such a placental insufficiency due to micro vascular disease and IUGR.

Other complications and managements are similar to preexisting DM.