Medical Disorders in Pregnancy Dr Than Than Yin

Obstetric cholestasis Unique to pregnancy Severe pruritus affecting limbs and trunk mainly palm and sole Developing in the second half of pregnancy (usually during the third trimester)

Diagnosis A typical history of pruritus without rash Abnormal liver function tests Moderate < less than three-fold elevation in transamimases ( ALT is the most sensitive) Raised ALP 9> pregnancy values Raised Ƴ glutamyl transpeptidase Mild elevation of bilirubin Increased total serum bile acid Exclusion of other causes of itching and abnormal liver function

Diagnosis To exclude other causes of abnormal liver function Liver scan Viral serology ( for hepatitis A,B,C and E,EBV and CMV) Liver autoantibodies( for pre-exisisting liver diseasse, anti-smooth muscle antibodies, antimitochondrial antibodies

Management Counselling Weekly LFT and bile acids No evidence of monitoring fetal well-being To check prothrombin time prior to delivery

Intrapartum management Labour may be induced at 37-38 weeks gestation if persistantly raised bile acid levels If bile acid levels < 40 µmol/L, reasonable to await spontaneous onset of labour

Drug therapy Vitamin K mandatoroy for women with prolonged prothrombin time, commenced at 32 weeks Antihistamine Ursodeoxycholic acid Dexamethasone Rifampicin Cholestyramine S-Adenosylmethionine Activated charcol Epomediol

Diagnosis BP, urinalysis, uric acid, platelet count, clotting screen, blood film Blood glucose, serum calcium, sodium, liver function tests CT or MRI EEG

Epilepsy in pregnancy Many cases are idiopathic 30% have a family history of epilepsy Secondary Epilepsy Previous surgery Intracranial mass or lesions Antiphospholipid syndrome

Effect of pregnancy on epilepsy A common indirect maternal death No effect in majority Women who have been seizure free for years are unlikely to have seizures in pregnancy Women with multiple type seizures are more likely to have increase in seizure frequency The risk of seizures is highest in peripartum Sudden Unexplained Death in Pregnancy (SUDEP)- risk factors seizure frequency Increasing number of antiepileptic drugs Low IQ Early onset epilepsy

Effect of epilepsy on pregnancy The fetus is relatively resistant to short periods of hypoxia No increased risk of miscarriage or obstetric complications Status epilepticus is dangerous for both mother and fetus The risk of child developing epilepsy is increased (4-5%) if either parent has epilepsy and, risk is 10-15% if both parents have epilepsy, 10% risk with previously effected sibling

Teratogenic risk of anti-epileptic drugs(AED) Phenytoin, primidone, phenobarbitone, carbamazepine, sodium valproate, lamotrigine, topiramate and levetiracetam all cross the placenta and are teratogenic Major malformations caused by AEDs Neural tube defects ( especially valproates 1-3.8% and carbamazepine 0.5-1%) Orofacial clefts ( particularly Phenytoin, carbamazepine, phenobarbitone and valproate) Congenital heart defects (particularly Phenytoin, phenobarbitone and valproate) Minor malformations Dysmorphic features Hypertelorism Hypoplastic nails and distal digits Hypoplasia of the mid face

Teratogenic risk of anti-epileptic drugs(AED) Metaanalysis of all studies showed that the risk of any one drug is approximately 6-7% Various theories Genetic deficiency of the detoxifying enzyme epoxide hydrolase Cytotxic free radicals Folic acid deficiency

Management Antenatal management Intrapartum management Folic acid 5mg daily No need to change the AED if epilepsy is well controlled Pre-natal screening for congenital abnormalities and detailed ultrasound at 18-20 weeks should be ordered, including fetal cardiac assessment Vitamin A 10-20mg daily should be prescribed in the last four weeks of pregnancy Intrapartum management Risk of seizures increase around the time of delivery 1-2% will have a seizure during labour and 1-2% will have a seizure in post partum 24 hours period Should continue regular AED Effective pain relief and epidural analgesia Postnatal management The neonate should recieve 1mg Vitamin K Inj IM Breast feeding should be encouraged

Cardiac disease in pregnancy Leading cause of maternal death as result of Myocardial infarction Ischemic heart disease Dissecting aortic aneurism Other heart disease Peripartum cardiomyopathy Rheumatic heart disease- 25% of pregnant population who not born in the UK Congenital heart disease

Management Preconception counselling Antepartum Intrapartum Postpartum Risk assessment Joint clinic attended by obstetrician, cardiologist, anaesthetist Echocardiogram Fetal echocardiogram for women with congenital cardiac disease 32-34 weeks gestation –multidisciplinary meeting for birth plan Intrapartum Early slow incremental epidural analgesia, assisted vaginal delivery Caesarean section is only necessary for obstetric indications Postpartum Anticoagulation Long observation in high dependency area Prophylaxis against postpartum haemorrhage Low dose oxytocin infusion

Thyroid disease in pregnancy Hyperthyroidism Hyperthyroidism Thyrotoxicosis complicates in 1 in 500 pregnancies 50% of affected women have a positive family history of autoimmune thyroid disease 95% are due to Grave’s disease, an autoimmune disorder caused by TSH receptor stimulating antibodies 1% of pregnancies Most cases have already been diagnosed Associated with autoimmune diseases, pernicious anemia, vitiligo, type 1 diabetes Commonest causes encountered in pregnancy- Hashimoto’s thyroiditis, treated Grave’s disease

Triiodothyronine (pmol/L) Pregnancy –specific normal ranges TSH(MU/l) Throxine (pmol/L) Triiodothyronine (pmol/L) Non-pregnant 0.27-4.2 12-22 3.1-6.8 1st trimester 0-5.5 10-16 3-7 2nd trimester 0.5-3.5 9-15.5 3-5.5 3rdt trimester 0.5-4 8-14.5 2-5.5