Antenatal care and maternal health Flashcards
What is the recommended dosage of folic acid and how long pre-conceptually should it be taken for?
40micrograms per day taken 3 months before pregnancy and in the first trimester.
If there is a history of epilepsy, NTD or obesity, 5mg/day is recommended.
What is the recommended dosage of vitamin D for pregnancy and breastfeeding?
10mg/day
Smoking increases the risks in pregnancy in what ways?
20-30% risk of miscarriage in first trimester compared to 10-15% in normal.
50% increased chance of premature labour.
x2 risk of low birth weight baby
Increased risk of sudden infant death syndrome.
When should booking ideally happen?
9-11 weeks gestation. Ideally before 12 weeks.
What examinations should be carried out at booking?
Weight
Baseline blood pressure to compare for assessment of pre-eclampsia and diagnose pre-existing hypertension.
Abdominal examination. The pregnant uterus is usually first felt at 12 weeks. If it is palpable before then, suggests multiple pregnancy. Fetal heart can usually be auscultated once the uterus is felt.
What do booking bloods include?
FBC - for anaemia
Rhesus status and blood group
Infections: syphilis (treat before 18 weeks), rubella (vaccinate mother when born), HIV (C-section, anti-retrovirals and no breastfeeding) and HepB (vaccinate baby when born)
How many antenatal visits are routine for a multiparous pregnancy? What happens in each of them?
16 weeks - review of test results and treat anaemia (below 11g/dl) if necessary.
18-20 weeks - anomaly scan. If placenta is found to cover the internal os, arrange scan at 36 weeks
28 weeks - Check Hb and red cell alloantibodies. Give first dose of anti-D to rhesus negative women.
34 weeks - second dose of anti-D
36 and 38 weeks - assess presentation and attempt ECV if breech
41 weeks - offer membrane sweep and date for induction
What additional antenatal appointments are offered to nulliparous women?
25 weeks, 31 weeks and 40 weeks.
What is the difference between a screening test and a diagnostic test?
A screening test tells you the chances of your baby being affected. A diagnostic test tells you for definite whether your baby has a condition or not.
What is the purpose of the dating scan? What is the combined test?
Looks at gestation, viability and multiple pregnancy. Can assess chorionicity in multiple pregnancy.
Combined test: a screen for chromosomal abnormalities. The nuchal translucency scan, with beta-HCG and PAPPA together forms the combined test for Down’s syndrome if integrated with maternal age. If the risk is high, CVS or amniocentesis will be offered.
Raised AFP levels can be a marker for NTD or gastroschisis.
When does the anomaly scan take place and what is assessed?
Observes and measures growth of baby and major organs including heart, limbs, kidneys. If abnormalities are found, counsel and offer CVS/amniocentesis and cardiac scan.
When is CVS used?
12-14 weeks gestation
When is amniocentesis used?
15+0 onwards
What is the purpose of fetal blood sampling?
Performed from 18 weeks onwards when blood can be aspirated from the umbilical vein. Usually used to determine haematocrit to guide red cell transfusion.`
What sensitising events should anti-D be given at?
Miscarriage or threatened miscarriage after 12 weeks Instrumentation of uterus Termination of pregnancy Ectopic pregnancy In utero procedures e.g. amniocentesis ECV Fetal death Antepartum haemorrhage
What is the Kleihauer test?
Assesses the number of fetal cells in the maternal circulation is performed within 2hrs of birth to detect occasional larger fetomaternal haemorrhages that require larger doses of anti-D to mop up.
What is the use of umbilical artery Doppler?
Evidence of high resistance circulation suggests placental dysfunction and can be indicative of fetal compromise. Helps identify which fetuses are actually growth restricted.
What should be assessed in a CTG?
Accelerations and variability >5 beats/min
Decelerations absent
Rate in range of 110-160
What is the risk of preterm labour in twins and triplets?
40% of twins and 80% of triplets deliver before 36 weeks.
In TTTS, what happens to the donor and recipient twins?
Results from unequal blood distribution through vascular anastomoses of the shared placenta. The donor is volume depleted and develops anaemia, IUGR and oligohydraminos. The recipient is overloaded and may develop polycythaemia, cardiac failure and polyhydraminos.
What is the treatment of TTTS?
Untreated, mortality is 90%.
Treatment with amnioreduction and septostomy or laser treatment.
What conditions predispose to breech presentation?
More room: polyhydraminos or high parity
Conditions which prevent turning: fetal/uterine abnormalities and twin pregnancies
Conditions preventing engagement: placenta praevia, pelvic tumours
How is ECV performed and how successful is it?
50% success rate.
Usually done under ultrasound guidance and in hospital to allow immediate delivery if complications occur. CTG is usually done afterwards and anti-D given to rhesus negative mothers. Sometimes made easier by administering a uterine relaxant.
ECV is contraindicated in what situations?
Fetal compromise
Contraindication of vaginal delivery
Ruptured membranes
Recent antepartum haemorrhage
How should a prolonged pregnancy be managed?
Check gestation.
At 41 weeks, VE and induce unless the cervix is not ripe or the patient prefers to wait. If not induced, sweep cervix and arrange daily CTG. If CTG is abnormal, deliver by CS.
What is thought to cause pre-eclampsia?
Endothelial cell damage in association with exaggerated maternal inflammatory response leading to vasospasm, increased capillary permeability and clotting dysfunction.
What are the risk factors for pre-eclampsia?
Nulliparity Previous hx FMHx Older maternal age Chronic hypertension Diabetes Multiple pregnancies, molar pregnancies, fetal hydrops (big placenta) Autoimmune disease e.g. antiphospholipid syndrome Renal disease Obesity
How is pre-eclampsia classified?
Mild - proteinuria and mild/moderate hypertension (140 or 150 systolic)
Moderate - proteinuria and severe hypertension with no maternal complications
Severe - proteinuria and hypertension <34 weeks or with maternal complications
What are the clinical features of pre-eclampsia?
Usually asymptomatic
Headache, drowsiness, visual disturbances, nausea/vomiting or epigastric pain
What are the complications of pre-eclampsia?
Cerebrovascular haemorrhage Eclampsia Renal failure Pulmonary oedema HELLP syndrome (haemolysis, elevated liver enzymes, low platelets)
What are the fetal complications of pre-eclampsia?
Accounts for 5% of stillbirths and 10% of preterm deliveries
At 34 weeks, IUGR
Increased risk of placental abruption
What investigations should be done for pre-eclampsia?
Urine dipstick PCR (protein creatinine ratio) Uric acid Hb Platelets LFT U&Es (for renal function) Monitoring should be continued 24 hours post partum.
How should pre-eclampsia be managed?
Twice weekly check of BP and urinalysis. USS every 2-4 weeks. Admit if severe hypertension, proteinuria 2+ or suspected fetal compromise.
Give antihypertensives labetolol or nifedipine if BP greater than 150/100. Magnesium sulphate should be given to prevent eclampsia.
If <34 weeks, give steroids to promote fetal lung maturation.
If mild, deliver by 37 weeks. If moderate, 34-36 weeks. If there are maternal complications, deliver the baby whatever the gestation.
When should OGTT for gestational diabetes be done?
24-28 weeks, or 16-18 weeks if previous GDM.
What are the risk factors for GDM?
PMHx of GDM Previous fetus >4.5kg First degree relative with diabetes BMI>30 Racial origin
What fetal complications are associated with maternal diabetes?
Congenital abnormalities
Preterm labour
Reduced lung maturity at any gestation
Increased birth weight, increased urine output and polyhydraminos
Shoulder dystocia
Fetal compromise, fetal distress and sudden fetal death are related particularly to poor third trimester glucose control
How is GDM managed?
Diet
Oral hypoglycaemic agents such as metformin.
Insulin
Postnatally, insulin is dicontinued but an OGTT should be performed at 3 months. 50% will be diagnosed as diabetics within the next 10 years.
What are the complications of PPROM?
> 50% of cases are followed by preterm delivery within 48 hours.
Chorioamnionitis or cord infection
Cord prolapse
Absence of liquor (usually before 24 weeks) can result in pulmonary hypoplasia and postural deformities.
What are the symptoms of chorioamnionitis?
Contractions Abdominal pain and uterine tenderness Fever tachycardia Coloured or offensive liquor
What investigations should be done at PPROM?
USS - may show reduced liquor
High vaginal swabs
Blood tests - FBC, U&E
CTG - persistent tachycardia suggests infection
How should PPROM be mentioned?
Admission and give steroids. Close maternal and fetal surveillance.
Induction is usually performed if gestation reaches 37 weeks.
If there is evidence of infection, IV antibiotics are given immediately and the fetus is delivered whatever the gestation.
What are some common causes of antepartum haemorrhage?
Placental abruption
Placenta praevia
Undetermined
What is the definition of APH?
Bleeding >5ml from the genital tract after 24 weeks of gestation. Occurs in 2-5% of pregnancies.
What are the complications of placenta praevia?
Prevents engagement
Severe haemorrhage
Placenta accreta
Placenta percreta
How is placenta praevia managed?
Admission for all women with bleeding and those with placenta praevia on USS
Ensure there is blood available - cross match
IV access
Anti-D given to rhesus -v women
Elective C-section at 39 weeks. In placenta accreta or percreta, the placenta may be left in situ or removed with the entire uterus.
What are the risk factors for placental abruption?
IUGR Pre-eclampsia Autoimmune disease Maternal smoking Previous hx Multiple pregnancy High parity Occasionally associated with trauma or a sudden reduction in uterine volume.
How do the presentations of placenta praevia and placental abruption typically differ?
In placenta praevia, there is often painless bleeds increasing in frequency and intensity over several weeks, although a third of women have not experienced bleeding before delivery.
In placental abruption, the uterus is tender and often contracting. In severe cases, the uterus is wood and the fetus is difficult to feel. The amount of bleeding does not reflect the degree of abruption.
How should placental abruption be managed?
Admission of pain and uterine tenderness.
Resuscitation and analgesia.
If there is fetal distress, C-section.
If there is no fetal distress but gestation is over 37 weeks, induce. If preterm, give steroids (<34) and monitor closely.
If the fetus is dead, coagulopathy is likely. Induce labour.
What does small for dates mean?
Below the 10% centile.
What are some constitutional determinants of small fetal size?
Low maternal weight and height
Nulliparity
Asian
Female
What are some pathological determinants of IUGR?
Existing maternal disease Maternal complications e.g. pre-eclampsia Mulitple pregnancy Smoking, drugs Infection e.g. CMV Extreme malnutrition Congenital/chromosomal abnormalities
What are the complications of CMV infection in pregnancy?
40% vertical transmission. Fetal diagnosis at amniocentesis at 20+ weeks.
10% of infected fetuses are severely affected. Deafness is common.
How is maternal carriage of group B strep managed?
Treatment with intrapartum penicillin of high risk groups and positive third trimester screen greatly reduces neonatal infection.
Which infections predispose to preterm labour?
Chlamydia and bacterial vaginosis
What are the complications of parvovirus infection in pregnancy?
Fetus develops anaemia and sybsequent hydrops. If IgM positive, surveillance for anaemia with middle cerebral artery Doppler and ultrasound. In utero transfusion if anaemia very severe.
How should the small for dates fetus be managed?
Growth is rechecked by USS fortnightly. A fetus which is growing consistently with a normal umbilical artery Doppler does not require intervention.
IUGR at term - if SFD and abnormal Doppler values, deliver by induction or CS.
If preterm, give steroids before 34 weeks with regular umbilical Doppler, CTG and consider delivery.
What are physiological changes to the cardiovascular system during pregnancy?
40% increase in cardiac output and 50% decrease in vascular resistance. BP often drops in the second trimester.
Increased blood flow often produces an ejection systolic murmur.
Left axis shift and inverted T waves are common on an ECG.
Pulmonary hypertension is associated with high maternal mortality.
Define maternal death
A death of a woman during pregnancy or within 42 days of its cessation, from any cause related to or aggravated by the pregnancy or its management ,but not accidental or incidental causes.
What is the difference between a direct death and indirect death?
Direct deaths are result from obstetric complications. Indirect deaths result from previous or new disease, which was not the result of pregnancy but nevertheless aggravated by it.
What are common causes of direct maternal death?
Sepsis (Group A strep)
VTE
Haemorrhage
Hypertensive disease
What are common causes of indirect maternal death?
Cardiac disease (congenital and acquired) Psychiatric disease (suicide) Other e.g. drug/alcohol, domestic violence, epilepsy and intracerebral haemorrhage.
