Pregnancy Flashcards
When do you give anti-D to non-sensitised Rh -ve mother’s?
28 and 34 weeks
In what situations should an anti-D be given within 72 hours
delivery of a Rh +ve infant, whether live or stillborn
termination of pregnancy > 10 weeks
miscarriage if gestation is > 12 weeks
ectopic pregnancy (if managed surgically, if managed medically with methotrexate anti-D is not required)
external cephalic version
antepartum haemorrhage
amniocentesis, chorionic villus sampling, fetal blood sampling
abdominal trauma
Tests for rehusus sensitisation ?
all babies born to Rh -ve mother should have cord blood taken at delivery for FBC, blood group & direct Coombs test
Coombs test: direct antiglobulin, will demonstrate antibodies on RBCs of baby
Kleihauer test: add acid to maternal blood, fetal cells are resistant (do after a sensitisation event to see if further foses of anti-d are required)
How will an affected fetus present - rhesus sensitisation
oedematous (hydrops fetalis, as liver devoted to RBC production albumin falls)
jaundice, anaemia, hepatosplenomegaly
heart failure
kernicterus
treatment: transfusions, UV phototherapy
Missed miscarriage
the fetus is no longer alive, but no symptoms have occurred
or
fetus no longer alive but closed os
Threatened miscarriage
vaginal bleeding with a closed cervix and a fetus that is alive
Inevitable miscarriage
vaginal bleeding with an open cervix
Incomplete miscarriage
retained products of conception remain in the uterus after the miscarriage
Complete miscarriage
a full miscarriage has occurred, and there are no products of conception left in the uterus
Anembryonic pregnancy
a gestational sac is present but contains no embryo
Diagnosing miscarriage
transvaginal ultrasound
Gravida (G)
is the total number of pregnancies a woman has had
Primigravida
refers to a patient that is pregnant for the first time
Multigravida
refers to a patient that is pregnant for at least the second time
Para (P)
refers to the number of times the woman has given birth after 24 weeks
Nulliparous (“nullip”)
refers to a patient that has never given birth after 24 weeks gestation
Primiparous
technically refers to a patient that has given birth after 24 weeks gestation once before (see below)
The term primiparous, or “primip” is a bit confusing. Technically, it refers to a woman that has given birth once before. However, it is often used on the labour ward to refer to a woman that is due to give birth for the first time (and has never given birth before). You may hear patients referred to on the labour ward as a “primip” when they have never given birth before.
when do fetal movements start?
20 weeks
If fetal movements have not yet been felt by 24 weeks, referral should be made to a maternal fetal medicine unit
vaccines in pregnancy?
Whooping cough (pertussis) from 16 weeks gestation
Influenza (flu) when available in autumn or winter
Live vaccines, such as the MMR vaccine, are avoided in pregnancy.
what is part of ‘booking bloods’ antenatal?
A set of booking bloods are taken for:
Blood group, antibodies and rhesus D status
Full blood count for anaemia
Screening for thalassaemia (all women) and sickle cell disease (women at higher risk)
Patients are also offered screening for infectious diseases, by testing antibodies for:
HIV
Hepatitis B
Syphilis
Screening for Down’s syndrome may be initiated depending on the gestational age. Bloods required for the combined test are taken from 11 weeks onwards.
What congenital abnormality is lithium associated with, especially in first trimester?
ebsteins anomaly
features of congenital rubella
Congenital deafness
Congenital cataracts
Congenital heart disease (PDA and pulmonary stenosis)
Learning disability
chickenpox in pregnancy complications
More severe cases in the mother, such as varicella pneumonitis, hepatitis or encephalitis
Fetal varicella syndrome
Severe neonatal varicella infection (if infected around delivery)
exposure to chicken pox during pregnancy? Investigation and management
When they are not sure about their immunity, test the VZV IgG levels. If positive, they are safe.
When they are not immune, they can be treated with IV varicella immunoglobulins as prophylaxis against developing chickenpox. This should be given within ten days of exposure.
chickenpox rash in pregnancy and > 20 weeks gestastion
oral aciclovir
congenital varicella syndrome
Fetal growth restriction
Microcephaly, hydrocephalus and learning disability
Scars and significant skin changes located in specific dermatomes
Limb hypoplasia (underdeveloped limbs)
Cataracts and inflammation in the eye (chorioretinitis)
why should pregnanct women avoid foods such as blue cheese, unpasteurised foods, processed meats
Listeriosis in pregnant women has a high rate of miscarriage or fetal death. It can also cause severe neonatal infection.
parovirus b19 in pregnancy?
Miscarriage or fetal death
Severe fetal anaemia
Hydrops fetalis (fetal heart failure)
Maternal pre-eclampsia-like syndrome
causes cleft lip/palate
polygenic inheritance
maternal antiepileptic use increases risk
definiton recurrent miscarriage
three or more consecutive miscarriages.
main causes of recurrent miscarriage
Idiopathic (particularly in older women)
Antiphospholipid syndrome
Hereditary thrombophilias eg factor V leidin
Uterine abnormalities
Chronic Histiocytic Intervillositis
Chronic histiocytic intervillositis is a rare cause of recurrent miscarriage, particularly in the second trimester. It can also lead to intrauterine growth restriction (IUGR) and intrauterine death.
The condition is poorly understood. Histiocytes and macrophages build up in the placenta, causing inflammation and adverse outcomes. It is diagnosed by placental histology showing infiltrates of mononuclear cells in the intervillous spaces.
Small for gestational age vs intrauterine growth restriction
Small for gestational age is defined as a fetus that measures below the 10th centile for their gestational age (doesn’t state if pathoplogical or not)
intrauterine growth restriction (IUGR), is when there is a small fetus (or a fetus that is not growing as expected) due to a pathology
causes of placenta mediated growth restriction
Idiopathic
Pre-eclampsia
Maternal smoking
Maternal alcohol
Anaemia
Malnutrition
Infection
Maternal health conditions
causes of non-placenta mediated growth restriction
Genetic abnormalities
Structural abnormalities
Fetal infection
Errors of metabolism
complications of fetal growth restriction
Short term complications of fetal growth restriction include:
Fetal death or stillbirth
Birth asphyxia
Neonatal hypothermia
Neonatal hypoglycaemia
Growth restricted babies have a long term increased risk of:
Cardiovascular disease, particularly hypertension
Type 2 diabetes
Obesity
Mood and behavioural problems
How is growth of fetus measured
symphysis fundal height (SFH) from 24 weeks
serial growth scans with umbilical artery doppler if need closer invetsigation due to:
- SFH being < 10th centile at 24 weeks
- Three or more minor risk factors
- One or more major risk factors
- Issues with measuring the symphysis fundal height (e.g. large fibroids or BMI > 35)
when is early delivery considered for small for gestational age?
when growth is static
defintion of low birth weight
less than 2500g
main risk for large for gestational age
shoulder dystocia
Investigations for a large for gestational age baby ?
Ultrasound to exclude polyhydramnios and estimate the fetal weight
Oral glucose tolerance test for gestational diabetes
causes macrosmia
Constitutional
Maternal diabetes
Previous macrosomia
Maternal obesity or rapid weight gain
Overdue
Male baby
defintion large for gestational age
large for gestational age (also known as macrosomia) when the weight of the newborn is more than 4.5kg at birth.
An estimated fetal weight above the 90th centile is considered large for gestational age.
what type of twin pregnancy has best outcomes?
diamniotic, dichorionic twin pregnancies
lambda sign or twin peak sign pregnancy
diamniotic, dichorionic
T sign pregnancy
Monochorionic diamniotic
no membrane separating twins pregnancy
monochorionic, monoamniotic
when are monoamniotic twins delivered, how?
elective caesarean section at between 32 and 33 + 6 weeks.
when are diamniotic twins delivered?
36 and 36 + 6 weeks for uncomplicated monochorionic diamniotic twins
37 and 37 + 6 weeks for uncomplicated dichorionic diamniotic twins
Vaginal delivery is possible when the first baby has a cephalic presentation (head first)
Caesarean section may be required for the second baby after successful birth of the first baby
Elective caesarean is advised when the presenting twin is not cephalic presentation
what do UTIs in pregnancy increase the risk of?
pre-term birth
testing for UTIs in pregancy
MSU for sensitivities and cultures routinely (at booking and at appointments) - treat asymptomatic bacteraemia during pregnancy
MSU and dip when symptomatic
folic acid dosage pregnancy
400mcg per day from prior to getting pregnant
Women with folate deficiency/epileptic drugs/pre-existing diabetes/BMI>30 are started on folic acid 5mg daily.
when are pregnant women screened for anaemia
Booking clinic
28 weeks gestation
cut offs for treating anaemia in women? in pregnancy and post partum
Hb
<115 non-pregnant
<110 first trimester (booking appt)
<105 2nd/3rd trimester
<100 post partum
anaemia treatment pregnancy
ferrous sulphate 200mg three times daily
what should people with B12 deficiency be tested for?
pernicious anaemia (checking for intrinsic factor antibodies).
investigation of choice DVT?
Doppler ultrasound
The Wells score is not validated for use in pregnant women. D-dimers are not helpful in pregnant patients, as pregnancy is a cause of a raised D-dimer.
investigations for pulmonary embolism : initial and definitive
Chest xray
ECG
There are two main options for establishing a definitive diagnosis: CT pulmonary angiogram (CTPA) or ventilation-perfusion (VQ) scan.
CTPA is the test for patients with an abnormal chest xray
CTPA carries a higher risk of breast cancer for the mother (minimal absolute risk)
VQ scan carriers a higher risk of childhood cancer for the fetus (minimal absolute risk)
Patients with a suspected deep vein thrombosis and pulmonary embolism should have a Doppler ultrasound initially, and if a DVT is present, they do not require a VQ scan or CTPA to confirm a PE. The treatment for DVT and PE are the same.
The Wells score is not validated for use in pregnant women. D-dimers are not helpful in pregnant patients, as pregnancy is a cause of a raised D-dimer.
Management of venous thromboembolism in pregnancy
low molecular weight heparin (LMWH). Examples of LMWH are enoxaparin, dalteparin and tinzaparin. The dose is based on the woman’s weight at the booking clinic, or from early pregnancy.
LMWH should be started immediately, before confirming the diagnosis in patients where DVT or PE is suspected and there is a delay in getting the scan. Treatment can be stopped when the investigations exclude the diagnosis.
When the diagnosis is confirmed, LMWH is continued for the remained of pregnancy, plus six weeks postnatally, or three months in total (whichever is longer). There is an option to switch to oral anticoagulation (e.g. warfarin or a DOAC) after delivery. An individual risk assessment is performed before stopping anticoagulation, with advice from a haematologist if necessary.
Management pregnant women with PE and haemodynamic compromise
Unfractionated heparin
Thrombolysis
Surgical embolectomy
pathophysiology pre-eclampsia
Pre-eclampsia is caused by high vascular resistance in the spiral arteries and poor perfusion of the placenta. This causes oxidative stress in the placenta, and the release of inflammatory chemicals into the systemic circulation, leading to systemic inflammation and impaired endothelial function in the blood vessels.
pre-eclampsia definition
NICE guidelines for diagnosis:
Systolic blood pressure above 140 mmHg
Diastolic blood pressure above 90 mmHg
PLUS any of:
Proteinuria (1+ or more on urine dipstick)
Organ dysfunction (e.g. raised creatinine, elevated liver enzymes, seizures, thrombocytopenia or haemolytic anaemia)
Placental dysfunction (e.g. fetal growth restriction or abnormal Doppler studies
Triad : hypertension after 20 weeks, proteinuria, oedema
what is eclampsia
seizures due to pre-eclampsia
which factors mean women will be offered aspirin for pre-eclampsia prophylaxis? how long given for?
From 12 weeks until birth
One high-risk factors:
Pre-existing hypertension
Previous hypertension in pregnancy
Existing autoimmune conditions (e.g. systemic lupus erythematosus)
Diabetes
Chronic kidney disease
2 or more moderate risk factors:
Older than 40
BMI > 35
More than 10 years since previous pregnancy
Multiple pregnancy
First pregnancy
Family history of pre-eclampsia
proteinuria in pregnancy values
Urine protein:creatinine ratio (above 30mg/mmol is significant)
Urine albumin:creatinine ratio (above 8mg/mmol is significant)
test to rule out pre-eclampsia
The NICE guidelines (2019) recommend the use of placental growth factor (PlGF) testing on one occasion during pregnancy in women suspected of having pre-eclampsia.
Placental growth factor is a protein released by the placenta that functions to stimulate the development of new blood vessels. In pre-eclampsia, the levels of PlGF are low.
NICE recommends using PlGF between 20 and 35 weeks gestation to rule-out pre-eclampsia.
management of pre-existing diabetes in pregnancy
folic acid 5mg
stick to metformin and insulin
aim for same levels as in gestational diabetes
retinopathy screening after booking and at 28 weeks
planned delivery between 37 and 38 + 6 weeks
complications of gestational diabetes
hypoglycaemia of newborn
macrosmia
Haemolysis
Elevated Liver enzymes
Low Platelets
HELLP SYNDROME - COMPLICATION OF PRE-ECLAMPSIA
management of gestational diabestes
Four weekly ultrasound scans to monitor the fetal growth and amniotic fluid volume from 28 to 36 weeks gestation.
The initial management:
Fasting glucose less than 7 mmol/l: trial of diet and exercise for 1-2 weeks, followed by metformin, then insulin
Fasting glucose above 7 mmol/l: start insulin ± metformin
Fasting glucose above 6 mmol/l plus macrosomia (or other complications): start insulin ± metformin
What can obstetric cholestasis cause?
still birth