Diabetes in Pregnancy – Long journey of gyn&obs

INTRODUCTION

5% pregnancies are complicated by diabetes
- 87.5% → gestational diabetes
- 7.5% → type1
- 5% → type 2
Risks to woman & fetus
- Miscarriage, pre-eclampsia & preterm labour are more common with pre-existing diabetes
- Diabetic retinopathy can worsen rapidly during pregnancy
- Stillbirth, congenital malformations, macrosomia, birth injury, perinatal mortality & postnatal adaptation problems are more common in babies born to women with pre-existing diabetes

PRECONCEPTION PLANNING AND CARE

Good blood glucose control before conception & continuing it throughout pregnancy reduces the risk of miscarriage, congenital malformation, stillbirth & neonatal death
Risks can be reduced but not eliminated
Important to avoid unplanned pregnancies & effective contraception
Provide information about how diabetes affects pregnancy and how pregnancy affects diabetes
Make sure woman enters pregnancy in best optimum health in order to avoid complications
BMI ≥27 offer advice on weight loss
Prescribe folic acid 5 mg/day to reduce risk of baby with neural tube defects

Monitoring of blood glucose & ketones in the preconception period

Offer monthly HbA1c to those diabetics planning to become pregnant
Teach self-monitoring of blood sugar levels& use of glucometer

Target blood glucose and HbA1c levels

Aim for same capillary plasma glucose target ranges as recommended for all people with type 1 diabetes
Aim to keep HbA1c levels below 48 mmol/mol (6.5%)
Advise against pregnancy if HbA1c level above 86 mmol/mol (10%)

Safety of medicine for diabetes before and during pregnancy

Metformin can be used
All other oral blood glucose-lowering agents should be discontinued before pregnancy & insulin substituted
First choice for long-acting insulin during pregnancy is isophane insulin NPH

Safety of medicines for complications of diabetes before and during pregnancy

Angiotensin-converting enzyme inhibitors, angiotensin-II receptor antagonists and statins should be discontinued before conception or as soon as pregnancy is confirmed

Retinal assessment in preconception period

Diabetic women seeking preconception care should be offered retinal assessment at their first appointment (if not done in last 6 months) and then annually if no retinopathy is found
Retinal assessment to be carried out by digital imaging with mydriasis using tropicamide

Renal assessment in the preconception period

Offer a renal assessment including measure of microalbuminuria
Refer to nephrologist if
- serum creatinine ≥120 micromol/liter
- urinary albumin:creatinine ratio >30 mg/mmol or
- estimated GFR <45ml/minute/1.73 m²

GESTATIONAL DIABETES

Risk assessment

Risk factors for gestational diabetes:
- BMI >30 kg/m2
- previous macrosomic baby weighing ≥4.5 kg
- previous gestational diabetes
- family history of diabetes (first-degree relative with diabetes)
Use above risk factors to determine the risk
Do not use fasting/random blood glucose, HbA1c, GCT or urinalysis for glucose to assess risk of developing GDM
On routine testing glycosuria of ≥2+ once or ≥1+ twice or more may indicate undiagnosed gestational diabetes. Consider further testing to exclude GDM

Testing

Use 2-hour 75g oral glucose tolerance test (OGTT) to test for gestational diabetes in women with risk factors
with previous history of gestational diabetes→
- offer early self-monitoring of blood sugar or a 75g 2-hour OGTT as soon as possible after booking & if results are normal a further test at 24-28 weeks
Any other women with risk factors→ offer a 75g 2-hour OGTT at 24-28 weeks

Diagnosis

Fasting plasma glucose level of ≥5.6 mmol/liter or
2-hour plasma glucose level of ≥7.8 mmol/liter

Interventions

Explain that treatment includes changes in diet, exercise +/- medicines
Teach self-monitoring of blood glucose
Refer all women with gestational diabetes to a dietician
Advise for regular exercise to improve blood glucose control & use food with low glycemic index
Target levels: same capillary plasma glucose target levels for women with gestational diabetes as for women with pre-existing diabetes

Regimens

Fasting plasma glucose <7 mmol/lit
- Trial of changes in diet & exercise
- Offer metformin if targets not met within 1-2 week
- Use insulin if metformin is contraindicated or unacceptable to woman or target levels not met
Fasting plasma glucose ≥7 mmol/lit
- Offer immediate treatment with insulin with or without metformin as well as changes in diet & exercise
Fasting plasma glucose 6.0-6.9 mmol lit
- Consider immediate treatment with insulin with or without metformin as well as change to diet & exercise.
Consider glibenclamide if blood glucose target are not achieved with metformin but who decline insulin therapy or who cannot tolerate metformin

ANTENATAL CARE FOR WOMEN WITH DIABETES

Monitoring blood glucose

Type 1 diabetics:
- fasting, pre-meal, 1-hour post-meal and bedtime blood glucose levels daily
Type 2 diabetes or GDM on multiple daily insulin injection regimen:
- fasting, pre-meal, 1-hour post-meal and bedtime blood glucose levels daily
Type 2 diabetes or GDM on diet & exercise or oral therapy or single dose insulin:
- fasting and 1-hour post-meal blood glucose levels daily

Target blood glucose levels

Any form of diabetics to maintain
- Fasting: 5.3 mmol/lit and
- 1 hour after meals: 7.8 mmol/lit or
- 2 hours after meals: 6.4 mmol/lit
Diabetics on insulin or glibenclamide to maintain capillary plasma glucose levels above 4 mmol/lit

Monitoring HbA1c

Measure HbA1c at booking in all pregnant women with pre-existing diabetes
Consider measuring in 2nd & 3rd trimesters
Risks for pregnancy increases if HbA1c level above 48 mmol/lit (6.5%)
Measure HbA1c in all women with gestational diabetes at the time of diagnosis (to exclude type 2 diabetes)

Managing diabetes during pregnancy

Consider using rapid-acting insulin analogues (aspart & lispro)
Having insulin-treated diabetes→ explain risks of hypoglycemia & must always have fast-acting form of glucose available
Consider continuous glucose monitoring for pregnant women on insulin: if having problematic severe hypoglycaemia or unstable blood glucose levels or to gain information about variability in blood glucose levels
Advise to seek urgent medical advice if type 2 diabetics or GDM become hypoglycemic or unwell
Test urgently for ketoanemia if pregnant woman with any form of diabetes presents with hypoglycemia or is unwell, to exclude diabetic ketoacidosis
- If suspected ketoacidosis during pregnancy→admit for critical level 2 care

Retinal assessment during pregnancy

Pre-existing diabetics→ offer retinal assessment by digital imaging with mydriasis using tropicamide after first antenatal clinical appointment (unless had assessment in last 3 months) and again at 28 weeks
diabetic retinopathy is present at booking→ additional retinal assessment at 16-20 weeks
any retinopathy found during pregnancy→ ophthalmological follow-up for at least 6 months after birth of baby

Renal assessment during pregnancy

Renal assessment not undertaken in preceding 3 months pre-existing diabetes→arrange it at first contact in pregnancy
Refer to nephrologist if
- serum creatinine ≥120 micromol/lit
- urinary albumin:creatinine ratio >30 mg/mmol or
- estimated GFR <45ml/minute/1.73 m²
Consider thromboprophylaxis for women with proteinuria >5g/day (macroalbuminuria)

Detecting congenital malformations

Offer ultrasound scan for detecting fetal structural abnormalities, including fetal heart at 20 weeks

Monitoring fetal growth and wellbeing

Offer USG monitoring of fetal growth and amniotic fluid volume every 4 weeks from 28 to 36 weeks

Timetable of antenatal appointments
APPOINTMENT	Care for women with diabetes during pregnancy
Booking appointment (ideally by 10 weeks)	Discuss how diabetes will affect pregnancy and early parenting Attended preconception care: advise to continue achieving optimal blood glucose control Not attended preconception care: give information, education and advice for the first time, take clinical history and review medicines Pre-existing diabetics: Offer retinal and renal assessment (unless done in last 3 months). Measure HbA1c Arrange follow up in joint diabetes and antenatal clinic every 1-2 weeks throughout pregnancy for all types of diabetes Women with history of GDM: offer self-monitoring of blood glucose or 75g 2-hour OGTT as soon as possible for those who book in first trimester Confirm viability and gestational age at 7-9 weeks
16 weeks	Pre-existing diabetics: offer retinal assessment at 16-20 weeks if retinopathy was present at first antenatal clinic visit Women with history of GDM: offer self-monitoring of blood glucose or 75g 2-hour OGTT as soon as possible for those who book in second trimester
20 weeks	Offer ultrasound scan for detecting fetal structural abnormalities including fetal heart examination
28 weeks	Offer ultrasound monitoring of fetal growth and amniotic fluid volume Offer retinal assessment to all women with pre-existing diabetes Newly diagnosed GDM (as result of routine antenatal testing at 24-28 weeks) enter care pathway
32 weeks	Offer USG monitoring of fetal growth and amniotic fluid volume
34 weeks	No additional or different care
36 weeks	Offer USG monitoring of fetal growth and amniotic fluid volume Provide information and advice about: timing, mode and management of birth; analgesia & anesthesia; changes to hypoglycaemic therapy during and after birth; care of baby after birth; initiation of breastfeeding and effects on blood glucose control; contraception and follow-up
37+⁰to 38+⁶ weeks	Offer IOL or caesarean section (if indicated) to women with type 1 or type 2 diabetes; otherwise await spontaneous labour
38 weeks	Offer testsof fetal wellbeing
39 weeks	Offer tests of fetal wellbeing Advice women with uncomplicated GDM to give birth no later than 40+⁶ weeks

Preterm labour in women with diabetes

Diabetes not a contraindication to antenatal steroids for lung maturation
Women on insulin, receiving steroids should be given additional insulin
Do not use betamimetic agents for tocolysis in women with diabetes

INTRAPARTUM CARE (Refer to NICE Intrapartum Care with medical disorders Click Here)

Timing and mode of birth

Discuss timing & mode of birth during antenatal appointment, especially during 3rd trimester
Type 1 or type 2 diabetes and no other complication
- Elective birth by induction or CS (if indicated) between 37+⁰ – 38+⁰ wks
- Consider elective birth before 37+⁰ wks in women with type 1 or type 2 diabetes if metabolic or any other feto-maternal complications
Women with GDM and no additional complications
- Elective birth by 40+⁶ wks
- Consider elective birth before 40+⁶ wk for women with GDM if feto-maternal complications
Diabetes in itself is not a contraindication to attempt VBAC
Women with USG diagnosed macrosomia explain the risks & benefits of vaginal birth, induction of labour & CS

Anaesthesia

Offer anaesthetic assessment in 3rd trimester to women with diabetes & comorbidities
If GA used→ monitor blood glucose every 30 minutes from induction of GA until after baby is born & woman is fully conscious

Blood glucose control during labour and birth

Monitor capillary plasma glucose every hour during labour & birth
- ensure to maintain it between 4 and 7 mmol/lit
- not maintained → use IV dextrose & insulin
Consider IV dextrose & insulin infusion in type 1 diabetes from onset of established labour

NEONATAL CARE

Initial assessment and criteria for admission to intensive or special care

Women with diabetes should give birth in hospital
Babies of diabetic mothers should stay with their mothers unless there is clinical complication or abnormal clinical signs that warrant admission to intensive or special care
Blood glucose testing routinely in babies at 2-4 hours after birth
Blood tests for polycythemia, hyperbilirubinaemia, hypocalcaemia and hypomagnesaemia for babies with clinical signs
Clinical signs of congenital heart disease or cardiomyopathy → perform an echocardiogram
Do not transfer babies to family care until they are
- at least 24 hours old
- feeding well and
- maintaining blood glucose levels
Feed the babies as soon as possible after birth (within 30 minutes) & then at frequent intervals (every 2-3 hours) until feeding maintains pre-feed capillary plasma glucose levels at a minimum of 2.0 mmol/lit
Criteria for admission of babies to neonatal unit:
- Hypoglycaemia with abnormal clinical signs,
- respiratory distress, signs of cardiac decompensation,
- signs of neonatal encephalopathy, signs of polycythemia,
- need for IV fluids,
- need for tube feeding,
- jaundice requiring intense phototherapy,
- babies born before 34 weeks

POSTNATAL CARE

Blood glucose control, medicines and breastfeeding

Insulin-treated pre-existing diabetics should reduce insulin immediately after birth and monitor blood glucose levels carefully. They are at increased risk of hypoglycaemia in postnatal period.
Women with GDM should discontinue blood glucose-lowering therapy immediately after birth.
Pre-existing type 2 diabetic women who are breastfeeding can resume or continue to take metformin and glibenclamide immediately after birth. Avoid other oral hypoglycaemia agents.
Continue to avoid any medicine for treatment of diabetes complications that were discontinued for safety reasons in preconception period.

Information and follow-up after birth

Women with pre-existing diabetes

Refer back to routine diabetes care arrangements
Remind importance of contraception & need for preconception care when planning future pregnancies

Women diagnosed with gestational diabetes

Test blood glucose to exclude persisting hyperglycaemia before discharge from hospital
Explain risk of GDM in future pregnancies a& offer testing for diabetes when planning future pregnancies
Offer annual HbA1c to woman diagnosed with gestational diabetes
Offer women diagnosed with GDM early self monitoring of blood glucose or OGTT in future pregnancies

Diagnosed with GDM and blood glucose levels returned to normal after birth:

Lifestyle advice (weight control, diet & exercise)
Offer fasting plasma glucose test 6-13 weeks after birth to exclude diabetes
If fasting plasma glucose test not done by 13 weeks→offer a fasting plasma glucose test or HbA1c after 13 weeks
Do not routinely offer 72g 2-hour OGTT

Fating plasma glucose below 6.0 mmol/lit or HbA1c <39 mmol/mol (5.7%):

Low probability of diabetes at present but should continue to follow lifestyle advice
Moderate risk of developing type 2 diabetes→should have annual tests

Fasting plasma glucose between 6.0 and 6.9 mmol/lit or or HbA1c between 39 and 47 mmol/mol (5.7% and 6.4%):