Chapter31 diabetes complicating pregnancy

Chapter31 diabetes complicating pregnancy mudaliar ppt

1. Mudaliar and Menon’s Clinical Obstetrics 13 th edition

2. Chapter 31 DIABETES COMPLICATING PREGNANCY

3. INTRODUCTION The prevalence of pre-existing diabetes and gestational diabetes has been increasing in South-East Asia. The rise in GDM and type II diabetes parallels the increasing incidence of obesity among women. Fetal and neonatal morbidity and mortality associated with diabetes in pregnancy can be prevented by meticulous prenatal and intrapartum care. Universities Press Pvt. Ltd

4. CLASSIFICATION OF DIABETES IN PREGNANCY IADPSG and FIGO: Diabetes in pregnancy (DIP) and gestational diabetes mellitus (GDM). DIP (overt or pregestational diabetes) Refers to diabetes that was diagnosed before the onset of pregnancy. Type I: There is absolute insulin deficiency Type II: There is defective insulin secretion or insulin resistance   Gestational diabetes mellitus (GDM) GDM is defined as carbohydrate intolerance resulting in hyperglycemia of variable severity with onset or first recognition during pregnancy Incidence: Globally: 1 – 28% , Indian women: 10-1- fold higher Universities Press Pvt. Ltd

5. CARBOHYDRATE METABOLISM IN NORMAL PREGNANCY During early gestation, insulin sensitivity increases, promoting the uptake of glucose into adipose stores to prepare for the energy demands of later pregnancy As gestation advances - surge of hormones including estrogen, progesterone, leptin, cortisol, placental lactogen and placental growth hormone - insulin resistance Blood glucose is slightly elevated - transported across the placenta to fuel the growth of the fetus During pregnancy, there is fasting hypoglycemia and postprandial hyperglycemia In the fasting state - triglycerides are broken down into fatty acids and ketones If starvation is prolonged, it leads to ketosis Universities Press Pvt. Ltd

6. GDM is a result of β-cell dysfunction and the chronic insulin resistance that develops during pregnancy. Lowering of glucose uptake by the cells induced by insulin resistance of pregnancy further contributes to hyperglycemia, overburdening the β-cells, which have to produce additional insulin in response. Once β-cell dysfunction begins, there is a vicious cycle of hyperglycemia, insulin resistance and further β-cell dysfunction. Universities Press Pvt. Ltd PATHOPHYSIOLOGY OF GDM

7. Risk Factors for GDM Overweight/obesity Excessive gestational weight gain Ethnicity Genetic polymorphisms Advanced maternal age Intrauterine environment Family and personal history of GDM PCOS Universities Press Pvt. Ltd

8. DIAGNOSIS OF GDM The World Health Organization (WHO) and Diabetes in Pregnancy Study Group, India (DIPSI), suggest a direct diagnostic test—the oral glucose challenge test (OGCT). Universities Press Pvt. Ltd Diagnostic test Week of gestation I diagnostic test Ideally, 12–16 weeks or at the time of the first visit for antenatal check-up II diagnostic test 24–28 weeks III diagnostic test 32–34 weeks

9. Universities Press Pvt. Ltd

10. 1. Single- step methods: Recommended by The International Association of Diabetes and Pregnancy Study Group (IADPSG), the WHO and the Government of India. Diabetes in Pregnancy Study Group India (DIPSI) method: 75 g of glucose in 300 mL of water irrespective of the time of her last meal - consumed slowly in about 5 minute’s time, to avoid nausea and vomiting Normal: 2-hour post-glucose load is <140 mg/dL. If the 2-hour post- glucose load is >140 mg/dL, then woman is she is considered as having positive for GDM. Repeat testing at 24–28 weeks and if found normal, the test should be repeated between 32 and 34 weeks. Universities Press Pvt. Ltd SCREENING METHODS

11. Universities Press Pvt. Ltd IADPSG criteria The woman comes after overnight fasting; her fasting plasma glucose level is checked. Then, the woman is given 75 g of glucose mixed with 150 mL of water or lime juice. The plasma glucose is checked at 1 and 2 hours. Cut-off values listed below: Fasting plasma glucose: 92 mg/ dL 1-hour plasma glucose: 180 mg/ dL 2-hour plasma glucose: 153 mg/ dL The WHO method Universal screening at 24–28 weeks of gestation using the 75 g, 2-hour glucose tolerance test (GTT) The woman comes in the fasting state and is given a 75 g glucose load A 2-hour plasma glucose value of ≥ 140 mg/dL is diagnostic of GDM

12. Universities Press Pvt. Ltd 2. Two- step method: The first step one is performed by giving a 50 g glucose challenge test irrespective of the woman’s last meal. Performed at 24–-28 weeks of gestation in women who do not have pre-existing diabetes. If the 1-hour plasma glucose is ≥ 140 mg/dL, then proceed to second step. Step two involves a 100 g glucose OGTT, where where the fasting plasma glucose level is determined, following which, 100 g of glucose is given orally and the plasma glucose level is checked at 1, 2 and 3 hours. A diagnosis of GDM is made if any two of the following values are abnormal: The cut-offs for plasma glucose values: Fasting plasma glucose: 95 mg/dL 1-hour plasma glucose: 180 mg/dL 2-hour plasma glucose:155 mg/dL 3-hour plasma glucose: 140 mg/dL

13. Effect of Pregnancy on GDM The insulin requirement increases gradually Ketosis There is a lowered threshold for glucose excretion in pregnancy   Universities Press Pvt. Ltd Maternal effects Fetal effects Neonatal effects Preterm labour Pre-eclampsia Infections Hydramnios Operative delivery Second- and third-trimester fetal loss Macrosomia Fetal death Hypertrophic cardiopathy Hypoglycemia Hypocalcemia Hyperbilirubinemia RDS Hypomagnesemia Polycythemia Unexplained neonatal death

14. MEDICAL MANAGEMENT Glycemic control Aim is to maintain two-hour postprandial plasma glucose (PPPG) level in the range of 110–120 mg/dL and fasting plasma glucose <95 mg/dL Dietary management—meal plan (medical nutrition therapy [MNT]) Calorie intake should start at 30 Kcal/kg of the ideal body weight Carbohydrates: 40–50% of the diet with complex carbohydrates with high fiber content Protein: 80–100 g/day of unless there is diabetic nephropathy (60 g) Fat intake: 30% of the diet - monounsaturated fats (>10%) and polyunsaturated fats (up to 10%) and saturated fats (<10%) Natural fibers: 30–35 g Divide the food intake into 3 meals and 3 snacks After 15 days, FBS and two-hour postprandial glucose levels are estimated, after breakfast If FBS is <95 mg/dL and PP glucose is <120 mg/dL, the woman is said to be under control by meal plan and the meal plan can be continued Universities Press Pvt. Ltd This Photo by Unknown Author is licensed under CC BY-SA-NC

15. PHARMACOTHERAPY Insulin First choice Started in a dose of 2-4 units, given 30 minutes before breakfast Two-hour PP levels are tested after two weeks. If the plasma glucose is within normal limits, i.e., within 120 mg/dL, continue the same dose of insulin is continued If the values are higher, then increase the dosage is increased by 2–4 units and the dosage should be adjusted once in 15 days only after testing two- hour PP glucose levels If the woman requires more than 16 units per day, then a split dose is given in the morning and in in the evening If insulin is used throughout the day, starting total dosage is 0.7 to 1 units/kg daily; divided with a regimen of multiple injections using intermediate-acting insulin in combination with rapid-acting insulin Metformin: Can be considered after 20 weeks of gestation for the medical management of GDM Universities Press Pvt. Ltd

16. Antenatal care is important to diagnose complications and to prevent macrosomia GDM in the first trimester , thyroid function test and HbA1C are also carried out . An HbA1C level of 5–6% is desirable. The incidence of major congenital malformations is more if the values rise to 9.5% or more Retinal and renal assessments are also carried out at first visit and again at 24 – 28 weeks of gestation First- trimester: 11- 14 weeks for nuchal translucency (NT) measurement A detailed anomaly scan is done between 18 and- 20 weeks of gestation Fetal echo: 24–26 weeks to detect any cardiac anomaly in the fetus Antenatal check-ups should be done once in 2 weeks until 32 weeks, and then, weekly. At each visit, complications should be looked for such as PIH, hydramnios and macrosomia and evidence of infections should be looked for FBS and PPBS (2 hours) should be performed once a month in GDM women on MNT and once in 2 weeks in women on insulin therapy Hospitalization: poor control of diabetes or if any complications develop Antepartum surveillance: non-stress test, biophysical profile, started at around 32 weeks in gestational diabetes with any complications Doppler studies: in cases complicated by pre-eclampsia Universities Press Pvt. Ltd OBSTETRIC MANAGEMENT IN GDM

17. GDM - well controlled on diet and no complications: pregnancy continued till near due date with fetal surveillance but not allowed to go beyond 40 weeks because of the risks such as macrosomia, shoulder dystocia and intrauterine death and induced at 39-40 weeks of gestation If GDM-being treated with insulin and well- controlled, induction of labor at 39 weeks of pregnancy. Elective preterm delivery - if the diabetes is poorly controlled with hydramnios and macrosomia or associated pre-eclampsia/ fetal compromise Universities Press Pvt. Ltd TIMING OF DELIVERY

18. If induction of labour is planned, normal diet and the usual insulin regimen are given until the patient is in established labour In established labour, the patient is kept NIL by mouth ; a n intravenous infusion is started with normal saline/dextrose saline Blood sugar and urine acetone are checked hourly Urea/electrolytes levels are checked on admission & thereafter every 4 hours In labour, blood sugar levels should be maintained between 90–120 mg/dL When the blood sugar level exceeds 120 mg%, 4 units of insulin is added to 500 mL of NS/RL to run at a rate of 100 mL per hour The insulin added to the infusion is gradually increased to 5 units, 6 units and so on depending on the blood sugar levels This is called the “sliding scale” Epidural analgesia is ideal for pain relief in labour. Universities Press Pvt. Ltd MANAGEMENT IN LABOUR:

19. MANAGEMENT IN LABOUR If oxytocin infusion is required for augmentation of labour, normal saline should be used Prophylactic antibiotics are started The fetus is closely monitored to detect fetal distress early As soon as the woman reaches the active stage of labor, the artificial rupture of membranes is performed to detect any meconium in the liquor Labor progress should be carefully monitored Cesarean section is performed if the baby is large or if there are other obstetrical indications such as fetal distress; in all cases of GDM, shoulder dystocia should be anticipated at the time of delivery Neonatal monitoring should be carried out to look for hypoglycemia and other complications Universities Press Pvt. Ltd

20. Mode of delivery Elective cesarean: Macrosomia, malpresentation, associated obstetrical factor or shoulder dystocia is anticipated Prophylactic antibiotics, diabetic control should be by sliding scale and thromboprophylaxis should be mandatorily administered Management in the puerperium Antibiotics to prevent infection in the immediate puerperium Breastfeeding may confer longer-term metabolic benefits on both the mother and offspring Postpartum care in women with GDM 50% risk of developing overt diabetes within 20 years 75 g OGTT between 6–12 weeks postpartum Universities Press Pvt. Ltd MANAGEMENT IN LABOUR

21. Neonatal problems Respiratory distress Hypoglycemia Cardiac anomalies Cardiac septal hypertrophy Hypocalcemia Polycythemia due to chronic hypoxia Hyperbilirubinemia Late neonatal effects Macrosomic babies Diabetes mellitus developing in the offspring Universities Press Pvt. Ltd

22. CONTRACEPTION Low-dose combined hormonal IUCD Injectable progestogens Universities Press Pvt. Ltd This Photo by Unknown Author is licensed under CC BY-NC

23. Established diabetes complicates 4 of 1,000 pregnancies. Depending on the duration of diabetes, there could be endothelial damage involving the kidneys, eyes and the cardiovascular system. Type I is insulin-dependent diabetes, occurs in younger women and is difficult to control during pregnancy. These women are prone to recurrent attacks of ketoacidosis and complications related to organ damage. Universities Press Pvt. Ltd PRE-GESTATIONAL OR OVERT DIABETES COMPLICATING PREGNANCY

24. PRECONCEPTION COUNSELLING Glycemic control is one of the most important aspects of preconception care. Ideally, HbA1C should be <6.5% to reduce the risk of congenital anomalies, pre-eclampsia, macrosomia and other complications. As the neural tube defects are increased, 5 mg tablet of folic acid supplementation should be given. Screening and treatment of diabetes complications should be done. Baseline glucose control and end-organ damage should be assessed, including renal function and retinopathy. In women who also suffer from hypertension, medications should be reviewed. ACE inhibitors are contraindicated. Cardiac assessment is very important in older women with long-standing diabetes. Those on oral hypoglycemic agents should be switched to insulin. Metformin use is safer in pregnancy. Universities Press Pvt. Ltd This Photo by Unknown Author is licensed under CC BY-NC-ND

25. CONTRAINDICATIONS FOR PREGNANCY Universities Press Pvt. Ltd

26. Miscarriage Fetal malformations Preterm delivery Pregnancy-induced hypertension and pre-eclampsia Deterioration of retinopathy, neuropathy and ischemic heart disease Placental insufficiency and IUGR Hydramnios Maternal infections: Urinary tract infections, especially pyelonephritis and monilial vulvovaginitis Unexplained fetal death Universities Press Pvt. Ltd EFFECT OF OVERT DIABETES ON PREGNANCY

27. Early pregnancy - lower insulin requirements and an increased risk for hypoglycemia in early pregnancy At 16 weeks - insulin resistance increases exponentially during the second and early third trimesters to 2–3 times the pre-prandial requirement and levels off toward the end of the third trimester with placental ageing A rapid reduction in insulin requirements can indicate the development of placental insufficiency Ketoacidosis Maternal ketonemia - impaired psychomotor development in the offspring Retinal changes and renal changes if present, may be aggravated during pregnancy Universities Press Pvt. Ltd EFFECT OF PREGNANCY ON OVERT DIABETES

28. Thyroid function test HbA1C Urine microalbuminuria and culture sensitivity Renal function test carried out every 4–6 weeks ECG Universities Press Pvt. Ltd INVESTIGATIONS

29. Medical management Insulin management in diabetic pregnancies: Insulin is the preferred agent for the management of both type 1 diabetes and type II diabetes in pregnancy. Oral hypoglycemic agents used prior to pregnancy - switched to insulin therapy once pregnancy is confirmed. These women should be carefully monitored for hyperglycemia/ hypoglycemia and keto-acidosis - hospitalised. The insulin requirement increases after 24 weeks of gestation and hence, the dosage should be adjusted based on the blood sugar levels, which should be checked periodically. Universities Press Pvt. Ltd MANAGEMENT OF PRE-EXISTING DIABETES IN PREGNANCY

30. MEDICAL MANAGEMENT Place of aspirin Women with type 1 or type 2 diabetes should be prescribed low-dose aspirin 60–150 mg/day (the usual dose is 81 mg/day) by the end of the first trimester in order to lower the risk of pre-eclampsia. Blood pressure: BP should be checked periodically to check for the development of hypertension/pre-eclampsia. Universities Press Pvt. Ltd

31. Fundoscopy at the first visit and repeated at 24 weeks and 36 weeks. Renal function should be assessed every 4–6 weeks by checking 24-hour urinary protein, blood urea, serum creatinine and urine culture. In older women with long-standing diabetes, cardiac evaluation should also be done every 4–6 weeks. All diabetic women should be seen at least every 2 weeks until 34 weeks, and then weekly until delivery. At each visit, complications such as PIH, hydramnios , FGR and macrosomia should be looked for. Hospitalization should be advised whenever there is poor control of diabetes, diabetic ketoacidosis or any other complications. Insulin resistance decreases dramatically immediately postpartum, and insulin requirements need to be evaluated and adjusted after delivery. Universities Press Pvt. Ltd ASSESSMENT OF MEDICAL COMPLICATIONS

32. FETAL SURVEILLANCE Viability scan Dating scan NT scan - nuchal scan is carried out at 11–14 weeks Down screening Detailed anomaly scan at 18–20 weeks, to rule out renal and cardiac anomalies, sacral agenesis and short femur should be carried out Maternal serum alpha-fetoprotein concentration is estimated at 16–20 weeks gestation in an attempt to detect neural tube defects in the fetus Fetal echo may be done at 24–26 weeks to detect any cardiac anomaly in the fetus Assessment of fetal growth is important to diagnose growth restriction—head and abdominal circumference are measured every 2–4 weeks from 24 weeks onwards for established diabetes complicating pregnancy Universities Press Pvt. Ltd

33. Assessment of fetal well-being Fetal well-being is assessed by performing a biophysical profile from 28 weeks onwards once in 2 weeks, and if necessary, more frequently If there is fetal growth restriction, daily CTG, biophysical profile and Doppler studies are carried out Timing of delivery If the fetal and maternal well-being are normal, termination of pregnancy is considered after 38 weeks Early delivery is indicated by maternal and fetal complications as indicated by fetal surveillance Post-delivery management There is a rapid decrease in the insulin requirement Women with type II diabetes who were on metformin and glibenclamide prior to pregnancy can resume the same dosage as before Management in the puerperium Antibiotics are given to prevent infection in the immediate puerperium Breastfeeding may confer longer-term metabolic benefits to both mother and offspring Universities Press Pvt. Ltd FETAL SURVEILLANCE

34. CONTRACEPTION Low-dose OC pills In diabetics with vascular disease, combined oral pills are contraindicated Progestogen-only contraception may increase insulin resistance Universities Press Pvt. Ltd This Photo by Unknown Author is licensed under CC BY-NC

35. NEONATAL PROBLEMS Respiratory distress, even in term babies The neonate should be assessed for hypoglycemia 1–2 hours, 4-6 hours and 24–48 hours after birth. Hypoglycemia is defined as <40 mg/dL in term neonates If hypoglycemia is diagnosed, IV glucose is given as per the newborn care protocols Careful cardiac assessment Hypocalcemia Hyperbilirubinemia Universities Press Pvt. Ltd