Maternal Disorders in Pregnancy Flashcards
What is the fall in BP during pregnancy?
30/15 mmHg during the second trimester
Returns to pre-pregnant levels by term
What causes hypertension in pregnancy?
Pregnancy-induced - BP rises above 140/90 after 20 weeks
- pre-eclampsia
- transient hypertension
Pre-existing - BP above 140/90 before 20 weeks
What is pre-eclampsia?
Hypertension
Proteinuria
Blood vessel endothelial damage + exaggerated immune response -> vasospasm, increased permeability and clotting dysfunction
What are risk factors for pre-eclampsia?
Nulliparity Previous history Family history Older age Chronic HTN Diabetes Twin pregnancy Autoimmune disease Renal disease Obesity
What are the classifications for pre-eclampsia?
Mild
- proteinuria
- mild/moderate HTN
Moderate
- proteinuria
- severe HTN with no complications
Severe
- proteinuria
- HTN before 34 weeks or with complications
How does pre-eclampsia occur?
Incomplete trophoblastic invasion of spiral arterioles so decreased uteroplacental blood flow
Ischaemic placenta + exaggerated maternal inflammatory response causes
- widespread endothelial cell damage
- vasoconstriction
- increased vascular permeability
- Clotting dysfunction
How does pre-eclampsia present?
Asymptomatic Headache Drowsiness Visual disturbances Nausea/vomiting Epigastric pain - complications impending HTN Oedema
What are maternal complications of pre-eclampsia?
Early onset more severe, any of these is indication to deliver
Eclampsia - grand mal seizure from cerebrovascular vasospasm -> hypoxia
Tx: magnesium sulphate
Cerebrovascular haemorrhage
Liver and coagulation problems - haemolysis (dark urine), elevated liver enzymes, low platelet count, DIC -> epigastric pain
Tx: magnesium sulphate
Renal failure
Pulmonary oedema -> adult respiratory distress syndrome
Tx: oxygen and frusemide
What are fetal complications of pre-eclampsia?
IUGR
Preterm delivery
Placental abruption
Morbidity and mortality
What investigations are done for pre-eclampsia?
Dipstick urine - if positive, rule out infection with culture
Protein:creatinine ratio (PCR) >30
Blood: high uric acid and Hb
- rapid fall in platelets
- rise in LFTs
USS - assess fetal growth
Umbilical artery Doppler and CTG
What is given to reduce risk of pre-eclampsia?
75mg aspirin
How is the severity of pre-eclampsia assessed?
Woman with new onset HTN is assessed in day unit
If symptomatic, proteineuria 2+, BP >160/110 or suspected fetal compromise then admitted
What medication is used in pre-eclampsia?
Antihypertensives if BP >150/10
- oral nifedipine
- IV labetalol
Magnesium sulphate
- prevents eclampsia
- increases cerebral perfusion
- indicates delivery should be done
When should babies be delivered with pre-eclampsia?
One or more complications are likely within 2 weeks of onset of proteinuria
Mild - deliver by 37 weeks
Moderate - 34-36 weeks
Severe - whatever the gestation by c-section
What medications can be used during labour with pre-eclampsia?
Induction with prostaglandin
Epidural
Antihypertensives
Oxytocin rather than ergometrine for 3rd stage
What postnatal care is done for pre-eclampsia?
Blood - LFT, platelets and renal monitored
Fluid balance
BP - beta-blocker, nifedipine, ACE inhibitor
What are risk factors for HTN before 20 weeks?
Older women
Obesity
FH
HTN with COCP
What blood pressure medication is contraindicated in pregnancy?
ACE inhibitors - give labetalol, methyldopa or nifedpine instead
What is red blood cell isoimmunisation?
Mother mounts immune response against antigens on fetal RBC
Antibodies cross placenta and cause fetal RBC destruction
What makes up the rhesus system?
Three linked gene pairs
Cc Dd Ee
DD or Dd is Rhesus positive
dd is Rhesus negative
What sensitizing events can occur in Rhesus disease?
TOP or ERPC after miscarriage
Ectopic pregnancy
Vaginal bleeding
How is Rhesus disease prevented?
Exogenous anti-D is given to mother
This mops up any fetal RBC in mother to prevent recognition by mother’s immune system
Given even if “father” is also Rhesus negative
Pointless if maternal anti-D is already present
When is Anti-D given?
At 28 weeks
Given within 72hr of sensitising event
Postnatally again if baby is Rhesus postive
Kleihauer test - if large amount of fetal RBC then extra large dose of Anti-D given
How does Rhesus disease manifest?
Neonatal jaundice
Neonatal anaemia
In utero anaemia -> cardiac failure, ascites, oedema
How are Rhesus disease women identified?
Screening at booking and 28 weeks gestation
If anti-D less than 10, fetal problem unlikely and levels are checked every 2-4 weeks
How is severity of fetal anaemia assesed?
Doppler USS of middle cerebral artery has high sensitivity to significant anaemia
Done fortnightly
If severe FBS done
How is fetal anaemia treated in utero?
If anaemia confirmed during FBS, Rhesus negative, high haemocrit blood is injected into umbilical vein
Done in increasing intervals until 36 weeks when baby is delivered
What effect does pregnancy have on glucose levels?
Diabetogenic - women with impaired glucose tolerance deteriorate to be classed as diabetic
Kidneys start excreting glucose at a lower blood glucose level so glycosuria may occr at physiological concentrations
What is gestational diabetes?
Carbohydrate intolerance diagnosed in pregnancy which may or may not resolve after pregnancy
Fasting glucose >7mmol
What fetal complications are associated with diabetes?
Congenital abnormalities (neural tube and cardiac) - 4x risk
Preterm labour - with reduced fetal lung maturity
Increased birthweight - fetal pancreatic islet cell hyperplasia -> hyperinsulinaemia and fat deposition
Polyhydramnios from increased urine output
Macrosomia -> shoulder dystocia and birth trauma
Increased fetal compromise, distress and sudden death
What maternal complications are associated with diabetes?
Increased insulin requirement
UTI and wound/endometrial infection after delivery
Pre-eclampsia more common
Worsens IHD
C-section and instruments more likely
Diabetic retinopathy often deteriorates
How is pre-existing diabetes managed in pregnancy?
Precise glucose control
Fetal monitoring for compromise
Appointments every 2 weeks up to 34 weeks and then weekly
Usual pregnancy scans + fetal echocardiogram
75mg aspirin from 12 weeks
How are babies delivered in maternal diabetes?
By 39 weeks
Elective c-section if weight >4kg
Neonate commonly develops hypoglycaemia - breast feed
What are risk factors for gestational diabetes?
Previous history Previous fetus >4,5kg Previous unexplained stillbirth First-degree relative with diabetes BMI >30 South Asian/Black Caribbean/Middle Eastern Polyhydramios Persistant glycosuria
How is gestational diabetes screened for?
Women with risk factors have GTT at 28 weeks
How is gestational diabetes managed?
Diet and exercise
Oral metformin
Insulin
Stop insulin at birth and GTT at 3 months
What are the physiological changes of cardiac function in pregnancy?
40% increase in cardiac output - increase in stroke volume and heart rate
40% increase in blood volume
How does pregnancy change the ECG?
Ejection systolic murmur
Left axis shift and inverted T waves
How does pregnancy affect women with pre-existing heart conditions?
Increased cardiac output acts as exercise test
Manifests after 28 weeks or during labour
How is cardiac disease managed in pregnancy?
Warfarin -> LMWH
ACE inhibitors -> beta-blockers
USS at 20 weeks may pick up cardiac anomaly which is more common
Check for anaemia
How is labour managed in ladies with cardiac disease?
Fluid balance check
Elective epidural
Elective forceps to reduce stress
Which cardiac diseases cause little problem in pregnancy?
PDA
VSD
ASD
Which cardiac diseases complicate pregnancy?
Pulmonary HTN (Eisenmenger’s syndrome) - pregnancy contraindicated
Aortic stenosis needs correcting before pregnancy - epidural may be contraindicated
Mitral valve disease - needs treating before
Peripartum cardiomyopathy - develops in last month of pregnancy or following 6 months
How is respiratory disease managed in pregnancy and labour?
Long term steroids need upping in labour as chronically suppressed adrenal cortex unable to produce adequate steroids
How does epilepsy affect pregnancy?
Seizure control can decrease in pregnancy/labour
Sodium valproate - neural tube defect
Newborn has 3% risk of developing epilepsy
What is optimum management of epilepsy in pregnancy?
Folic acid + carbamazepine or lamotrigine
Oral vit K
20 week USS and EKG important to rule out abnormalities
What effect does hypothyroidism have on pregnancy?
Miscarriage
Preterm delivery
Intellectual impairment
Pre-eclampsia
Monitor TSH, dose may need increasing
How does hyperthyroidism affect pregnancy?
Antithyroid antibodies can cross placenta -> neonatal thyrotoxicosis and goitre
Maternal thyrotoxicosis may improve in late pregnancy
If poorly controlled -> thyroid storm with acute symptoms and heart failure near delivery
How is hyperthyroid treated in pregnancy?
PTU as less likely to cross placenta than carbimazole
Use lowest dose
Safe when breastfeeding
What is postpartum thyroiditis?
Can cause postnatal depression
RF: antithyroid antibodies and type I diabetes
What are risk factors for Acute Fatty Liver of Pregnancy?
Primips
Male babies
Twins
May be on spectrum of pre-eclampsia
How does fatty liver present?
Malaise Vomiting Jaundice Vague epigastric pain Thirst
Acute hepatorenal failure
DIC
Hypoglycaemia
What is intrahepatic cholestasis of pregnancy?
Itching without skin rash and with abnormal LFTs
Abnormal sensitivity to cholestatic effects of oestrogen
What is intrahepatic cholestasis of pregnancy associated with?
Sudden stillbirth
Preterm delivery
Maternal and fetal haemorrhage
Reocurrs
How is intrahepatic cholestasis of pregnancy managed?
Vit K from 26 weeks
UDCA for itching
Induction at 38 weeks
What is antiphospholipid syndrome (APS)?
Lupus anticoagulant +/- anticardiolipin antibodies occur in association with adverse pregnancy complications
Placental thrombosis
Recurrent miscarriage
IUGR
Early pre-eclampsia
How is APS managed?
Aspirin and LMWH
Serial USS and elective induction at term
Postnatal anticoagulation to prevent VTE
What is the impact of pregnancy on renal system?
GFR increases by 40%
Urea and creatinine levels decrease
How is chronic renal disease managed in pregnancy?
Proteinuria can cause diagnostic confusion with pre-eclampsia
Pre-eclampsia
IUGR
Polyhydramnios
Preterm delivery
What effect do urinary infection have on pregnancy?
Preterm labour
Anaemia
Pyelonephritis
What effect does pregnancy have on the clotting system?
Pregnancy is prothrombotic - VTE 6x
Increased blood clotting factors
Decreased fibrinolytic activity
Pulmonary embolus and DVT need to be avoided - treat with LMWH
What thromboprophylaxis is given in pregnancy?
Compression stockings
Antenatal and postnatal LMWH given if:
- previous VTE or needed in pregnancy (6 weeks)
- increased BMI, smoker, age, elective c-section, labour >24 hours
What are complications of obesity in pregnancy?
Maternal
- thromboembolism
- pre-eclampsia
- diabetes
- C-section
- wound infection
- PPH
Fetal
- congenital abnormalities
- increased perinatal mortality
How is obesity managed?
Folic acid and vit D
Maintain weight in pregnancy
Which psychiatric drugs are used in pregnancy?
Prefer to stop lithium, but monthly monitoring if continued
SSRIs (preferably fluoxetine)
AVOID paroxetine, clozapine and olanzapine
What risks are associated with opiate abuse?
Preterm delivery IUGR Stillbirth Developmental delay SIDS
What risks are associated with cocaine abuse?
Teratogenic IUGR Placental abruption Preterm delivery Stillbirth SIDS
What risks are associated with ecstasy abuse?
Cardiac defects
Gastroschisis
What risks are associated with benzo abuse?
Facial clefts
Neonatal hypotonia
What does smoking increase the risk of?
Miscarriage IUGR Preterm birth Placental abruption Stillbirth SIDS
What is the effect of pregnancy on anaemias?
Increase in blood volume leads to decrease in Hb concentration
New normal = 110
Give oral iron and folic acid
