Some Medical Conditions in Pregnancy

1. Some Medical Conditions in Pregnancy Max Brinsmead PhD FRANZCOG July 2010

2. Anaemia • The most common pregnancy complication worldwide • Affects 1:2 women in developing countries • ↑ Risk of maternal and fetal mortality • Also has substantial morbidity and economic sequelae

3. Haematocrit and Perinatal Mortality

4. A Definition of Anaemia: • WHO definition is Hb <11.0 g/dL but… • Hb <10.0 is more realistic • Needs correction for altitude… • Add 2.5 for every 1000m up to 4000m • Severe when Hb is 4.0 – 7.0 • Very severe when Hb is <4.0

5. Causes of Anaemia: • Nutritional deficiency of Iron and Folate • Malaria • HIV (+/- TB) • Sickle cell Disease or Thalassaemia • Hookworm infestation • Chronic renal or Hepatic disease • Often multifactorial

6. Losses and gains: • Non pregnant iron requirement is 2 mg/day • But this reaches 5 mg/day in 3rd trimester • Will be influenced by age, parity, pregnancy spacing and fetal number • Hookworm >1000 ova/g faeces will cause a loss of 2 mg iron/day • Folate deficiency commonly nutritional but it is aggravated by malaria • B12 deficiency is rare

7. Investigations for Anaemia: • Blood film – look for micro or macrocytosis, reticulocytes, segmentation neutrophils, Neutrophil & Lymphocyte count • Small RBC’s (microcytic) that are pale in colour (hypochromic) = Iron deficiency • Large RBC’s (macrocytic) = Folate deficiency • Reticulocytes indicate rapid RBC turnover • But combined deficiencies can be difficult • Because the RBC’s may be normocytic • Malarial parasites may be intermittent or parasitised RBC’s may have been removed from circulation • Bone marrow can be useful

8. Profound Anaemia or Pre eclampsia? • Oedema can occur with hyperdynamic heart failure • Proteinuria can occur with renal hypoxia • There can be hypovolaemia with both • Profound anaemia may even present with coma • But… • Diastolic BP will be low with anaemia and high with pre eclampsia

9. Management of Profound Anaemia: • Admit to hospital if HB is <6.0 • Try to be as specific as possible with Rx • Iron dextran infusion can be useful • Calculate dose required • Adrenaline & hydrocortisone on standby • Follow up • Indiscriminate Fe by IM injection is not good • Parenteral folate rarely required but concomitant oral iron always required

10. Indications for Transfusion: • Heart failure or incipient heart failure • HB < 4.0 • Miscarrying or in labour and HB<6.0 • Operation required and HB <8.0 • Other disease is present e.g. renal

11. Maternal Mortality and Transfusion

12. Transfusion Precautions: • Use packed cells and pre transfusion Lasix • May require anti malarial drugs • May require lower limb torniquets • NB The Haematocrit will initially fall

13. The anaemic patient in labour: • Do everything possible to minimise blood loss • Because they may have compensated up to that point but blood loss of even 100 – 200 ml may be fatal • Monitor for signs of fetal hypoxia • Maternal oxygen can be useful

14. The anaemic patient who fails to respond to treatment: • Maybe noncompliant • Has underlying renal or hepatic disease • Has chronic infection such as HIV, TB or UTI • Has concomitant malignancy • Has an advanced abdominal pregnancy • Has idiopathic hypoplastic anaemia

15. Thrombocytopenia and Pregnancy • Platelet count in pregnancy is normally >150,000 • Thrombocytopenia may be due to: • Malaria e.g. hyperactive spleen disease • HIV • And transiently with other viral infections • Part of severe anaemia e.g. folate deficiency • Many drugs including alcohol • Fetal death in utero • Late sign in severe pre eclampsia (HELLP) • Idiopathic thrombocytopenia

16. IdiopathicThrombocytopenia(or ITP) • Is actually an autoimmune condition due to anti-platelet antibodies • Maternal risk of bleeding does not occur until the platelet count is <20,0000 • However, there is a risk of passive transfer of antibody and fetal thrombocytopenia • That may result in intra cranial haemorrhage • This can be averted by keeping maternal count >50,000 • This is done by the administration of steroids

17. Thyroid Disorder • Pregnancy is a state of mild hyperthyroidism • Thyroid hormones cross the placenta poorly But • The developing fetal brain may be dependent on some maternal thyroxin And • Antithyroid drugs cross the placenta readily

18. Management of Thyroid Disordersin Pregnancy • Hypothyroid patients require an increase in their thyroxin replacement therapy • Best option is to dose by 33% ASAP • Hyperthroid patients are best treated by PTU but “run them hot” • I131 therapy is contraindicated • Thyroid surgery is okay after toxic control

19. This is the hand of a 14-year primigravida whom you are seeing for the first time…

20. Finger Clubbing here is most likely due to… • Cyanotic congenital heart disease • Tetralogy of Fallot • Eisenmenger’s Syndrome • And you should be worried because there is a very poor prognosis • For the mother • For the fetus • Other High Risk Cardiac Conditions • Pulmonary hypertension • Severe aortic & mitral stenosis • A metal mitral valve replacement (on Warfarin) • Marfan’s syndrome with severe aortic incompetence • Peripartum cardiomyopathy

21. Management of Cardiac Diseasein Pregnancy • Cardiac output increases throughout pregnancy and reaches a peak in labour • Close monitoring with multidisciplinary care is required • Low threshold for hospitalisation • Vigorous treatment of CCF • Aim for vaginal delivery • Pre term delivery may be required for severe disease • Remember thromboprophylaxis

22. Management of Cardiac Diseasein Labour • Best done as “intensive care” • Low dose epidural good • But requires an expert anaesthetist • Assist the delivery by ventouse or forceps in a semi sitting position • Avoid all oxytocics in the third stage • And use mechanical means to control PPH • LMW heparin prophylaxis against thromboembolism • Progesterone only or T/L best afterwards

23. Diabetes in Pregnancy Max Brinsmead PhD FRANZCOG March 2010

24. Types and Incidence • KNOWN DIABETIC (Before pregnancy) • Insulin dependent – Type 1 or Juvenile Onset Diabetes • NIDM – Type 2 or Maturity Onset Diabetic • Together account for <1% of pregnancies • GESTATIONAL DIABETES • Diagnosed during a pregnancy • May or may not resolve after pregnancy • Comprise 2 – 9% of pregnancies depending on the population

25. Glucose Metabolism in Pregnancy • Pregnancy is a diabetogenic stress • Results from antagonism of insulin by placental hormones • HPL, Sex steroids and corticosteroids • The diabetogenic stress increases as pregnancy advances • But reverses quickly after placenta delivers • BUT… • Facilitated transfer of glucose to the parasitic fetus  fasting hypoglycaemia

26. The Effect of Diabetes on Pregnancy •  Maternal blood sugar will •  Fetal blood sugar and… •  Fetal insulin • This causes… •  Fetal growth which  • Dystocia  Caesarean or shoulder difficulties  • Brachial plexus palsy • BUT • Fetal brain growth is reduced • Lung maturation is delayed • And the neonate is at risk of hypoglycaemia & hypocalcaemia

27. Effect of Diabetes on Pregnancy (2) •  Fetal blood sugar will cause •  Fetal glycosuria • Polyhydramnios • There is risk of intrauterine death • ?due to hypoxia • ?due to ketoacidosis • There is Rate of maternal Pre eclampsia • ?due to placental bed vasculopathy • There are Risks of Prematurity • Some of which is due to intervention on behalf of the mother

28. Extra Risks for Type 1 Diabetics • First trimester hyperglycaemia causes… • Rates of congenital malformation (CNS & Heart) • If there is diabetic vasculopathy then the inevitable kidney damages causes… • Rates of pre eclampsia • Risk of fetal growth retardation

29. The Effect Pregnancy on Diabetes • Insulin antagonism  Insulin requirements • Pregnancy is a state of lipidolysis so IDDM patients are at risk of ketoacidosis • Especially during labour • Will be complicated by nausea, vomiting & slow gastric emptying • And altering energy expenditure • A desire for tight glucose control and a parasitic fetus puts the mother at risk of serious hypoglycaemia • Retinopathy and nephropathy may deteriorate rapidly • Insulin requirements change rapidly after delivery

30. Principles of Management • Family Planning • Stringent blood glucose control before pregnancy • Monitor HBA1c • Meticulous blood glucose control throughout pregnancy • Multidisciplinary care from Physician, Dietition, Nurse Educator and Obstetrician • Watch for known complications • Timely delivery • Appropriate mode of delivery • Family Planning

31. Controversies in Gestational Diabetes • Selective or universal testing • At least 50% missed unless all screened • Can obstetric outcomes be changed? • These questions answered by the 2005 ACHOIS study • Glucose challenge or GTT • 75G one hour test is best for screening • Criteria for diagnosis • Criteria for the use of insulin • Role of oral hypoglycaemic drugs • Thought to be teratogenic in the 1st trimester

32. Criteria for Selective Testing • First degree affected relative • Age >35 years • Ethnic origin • Obesity • Poor obstetric history esp. “unexplained stillbirth” • Previous fetal macrosomia • Clinical suspicion • Polyhydramnios • Macrosomia

33. Criteria for the Diagnosis • May begin with Fasting and 2 hr Postprandial GLUC • If Fasting >7.8 or • 2 hr PP >11.0 then… • This patient requires insulin ASAP • Best test is the WHO 75G GTT • Diabetes is Fasting GLUC >5.4 or… • 2 hr PP >7.8

34. Management Goals for Gestational Diabetes • Diet • Abstinence from all simple sugars • Reduce fats and oils • Regular meals with complex CHO • Exercise • Self-tested blood glucose 4x  once daily • Aim for Fasting GLUC <5.5 • And 2 hr PP <7.0 • Insulin 3 – 4 x daily if GLUC exceed these • Cease any insulin at delivery • Repeat 75g GTT after 8 – 12 weeks

35. Delivery of the Pregnant Diabetic • Timing for Type 1 diabetics is often a juggle between difficult sugar control and fetal maturity • ?role for Betamethasone for the fetal lungs • Low threshold for Caesarean especially if fetal macrosomia is suspect • Most gestational diabetics induced at term i.e. >37 completed weeks • but wait for spontaneous or induced Cx ripening • Monitor GLUC in labour • May require dextrose and insulin by infusion for those who are insulin-dependant • Monitor the fetus in labour