Antenatal care Flashcards
prophylaxis for neutral tube defects
5mg in first trimester
ideally begun 3 months before pregnancy
which conditions increased risk of neural tube defects
Epilepsy
Previous baby with neural tube defects
Obesity with BMI over 35
Diabetes (Type 1 and 2)
Sickle cell disease
Thalassemia
Malabsorption disorders (e.g. Crohn’s disease)
Those taking folate antagonist drugs (HIV anti-retroviral drugs, methotrexate, sulphonamides
reduce risk of rickets and when higher dose
vit d
if darker skin/BAME group or BMI>30 higher dose
what check for in maternal blood
maternal blood grouping and rhesus
how assess foetal growth
symphysis fundal height
indications for regular USS as unsuitable for SFH measurements
Multiple pregnancy
BMI >35
Large or multiple fibroids
how reduce incidence of foetal growth restrictions
low dose aspirin
lifestyle advice
-food
-exercise
-smoking
- alcohol
- recreational drugs
- travel
food -avoid raw meat, fish, eggs, unpasteurised milk or cheese, pate and shellfish
fruit and veg washed (reduce toxoplasmosis)
exercise - not vigorous (risk of small baby), avoid high contact
smoking - cessation
alcohol - avoid
recreational drugs - cocaine (spontaneous abortion, placental abruption, growth restriction, sudden infant death syndrome). if opiate addicted - methadone programme
travel - counsel about increased risk of VTE…compression stockings
reduced foetal movements advice
no change to pattern of movements after 28 weeks
if change - lie on left side and focus on movements for 2 hours, if less than 10 contact maternity unit
N+V advice
4th and 7th week
should settle by week 20
ginger and acupuncutre to help. ir prolonged and severe - tx for hyperemesis gravidarum
heartburn advice
sitting up for meal
avoid fat and spice
smaller portions
consider gaviscon or omeprazole
constipation advice
fibre and oral fluids
small for gestational age definition
an infant with a birth weight <10th centile for its gestational age.
Severe SGA – a birth weight < 3rd centile.
foetal SGA definition
an estimated fetal weight (EFW), or abdominal circumference (AC) <10th centile.
Severe fetal SGA – an EFW or AC <3rd centile.
foetal growth restriction definition
when a pathological process has restricted genetic growth potential. This can present with features of fetal compromise including reduced liquor volume (LV) or abnormal doppler studies.
low birth weight
<2500g
types of small for gestationages ages
normal - growth follows normal centiles
placenta mediated growth restriction - foetal growth restriction….placental insuffiency from substance abuse, DM, renal disease etc
non placenta mediated growth restriction - foetal factors such as chromosomal or structural anomaly
minor risk factors for SGA
maternal age same or more 35
smoker 1-10/day
nullparity
BMI<20 OR 25-34.9
IVF singleton
previous pre eclampsia
preg interval <6or >60 months
low fruit intake pre preg
major risk factors for SGA
maternal age >40
smoker>11
previous SGA baby
maternal/paternal SGA
previous stillbirth
cocaine use
daily vigorous exercise
maternal disease
heavy bleeding
low PAPP-A
how diagnosed SGA
USS
ratio of head circumference and AC (if assymetric - placental insufficiency)
doppler studies
reduced amnotic fluid vol
other - Detailed fetal anatomical survey
Uterine artery Doppler (UAD)
Karyotyping
Screening for infections including congenital cytomegalovirus, toxoplasmosis, syphilis and malaria
mx of SGA
prevention - smoking cessation etc, high risk of pre eclampsia - 75mg of aspirin
UAD suveillance or SFH
antenatal steroids if early delivery considered
neonatal complications SGA
birth asphyxia
meconium aspiration
hypothermia
hypo/hyperglycaemia
polycythaemia
retinopathy of prematurity
persistent pulmonary HTN
pulmonary haemorrhage
necrotising entercolitis
long term complications SGA
cerebral palsy
type 2 DM
obesity
HTN
precocious puberty
behavioural problems
depression
alzheimers
cancer
post term pregnancy definition
a pregnancy extending past 42 weeks gestation (term refers to the 37-42 week gestation period)
post dates pregnancy definition
a pregnancy extending past the estimated delivery date (EDD), also known as due date at 40 weeks gestation
risk factors for prolonged pregnancy
Nulliparity
Maternal age >40
Previous prolonged pregnancy
High body mass index (BMI)
Family history of prolonged pregnancies
primary concern of prolonged pregnancy
stillbirth
clinical fx of prolonged pregnancy
Static growth or potentially macrosomia
Oligohydramnios
Reduced fetal movements
Presence of meconium
Signs of meconium staining e.g. on nails
Dry / flaky skin with reduced vernix
ddx of prolonged pregnancy
inaccurate dating
ix of prolonged pregnancy
dating in first trimester scan
USS scan
mx of prolonged pregnancy
Membrane sweeps – can be offered from 40+0 weeks in nulliparous and 41+0 weeks in parous women.
Induction of labour – usually offered between 41+0 and 42+0 weeks gestation
patho red cell isoimmunisation
maternal antibodies are formed in response to surface antigens on fetal erythrocytes. It occurs when the fetal cells enter the maternal circulation via a ‘sensitising event‘ – such as an antepartum haemorrhage or abdominal trauma. It can also occur during delivery.
in subsequent pregnancies, maternal antibodies can cross the placenta and attack the fetal red blood cells (if they carry the same surface antigen). This leads to haemolysis and subsequent fetal anaemia.
examples of surface antigens in maternal isoimmunisation
rhesus D blood group
rhesus D positive scenario
A woman is RhD-, and her partner is RhD+. She becomes pregnant with a fetus that is also RhD+. During childbirth, she comes into contact with the fetal (RhD+) blood, and antibodies are produced (known as anti-D antibodies).
She later becomes pregnant with a second child that is also RhD+.
The woman’s anti-D antibodies cross the placenta during this pregnancy and enter the fetal circulation, which contains RhD+ blood. They bind to the fetus’ RhD antigens on its erythrocyte surface membranes.
This causes the fetal immune system to attack and destroy its own RBCs, leading to fetal anaemia. This is termed haemolytic disease of the newborn
anti-d immunoglobulin when given
rhesus d negative women in any sensitising event such as invasive obstetric testing, antepartum haemorrhage, ectopic preg, miscarriage, fall, intrauterine death, termination of preg, delivery etc
ix rhesus D-ve women
maternal blood group and antibody screen
deto-maternal haemorrhage test
LMP
to the date of the first day of the most recent menstrual period
Gestational age
to the duration of the pregnancy starting from the date of the last menstrual period
Estimated delivery date def
to the estimated date of delivery (40 weeks gestation)
primigravida
a patient that is pregnant for the first time
multigravida
a patient that is pregnant for at least the second time
Para
refers to the number of times the woman has given birth after 24 weeks gestation, regardless of whether the fetus was alive or stillborn
nulliparous
refers to a patient that has never given birth after 24 weeks gestation
primiparous
refers to a patient that has given birth after 24 weeks gestation once before
multiparous
refers to a patient that has given birth after 24 weeks gestation two or more times
gestation age described
gestational age is described in weeks and days. For example:
5 + 0 refers to 5 weeks gestational age (since the LMP)
13 + 6 refers to 13 weeks and 6 days gestational age
gravidity and parity description
A pregnant woman with three previous deliveries at term: G4 P3
A non-pregnant woman with a previous birth of healthy twins: G1 P1
A non-pregnant woman with a previous miscarriage: G1 P0 + 1
A non-pregnant woman with a previous stillbirth (after 24 weeks gestation): G1 P1
trimesters
The first trimester is from the start of pregnancy until 12 weeks gestation.
The second trimester is from 13 weeks until 26 weeks gestation.
The third trimester is from 27 weeks gestation until birth.
when foetal movements
20 weejs
milestone <10 weeks
booking clinic
baseline assessment and plan
10 and 13+6 key milestone
dating scan
An accurate gestational age is calculated from the crown rump length (CRL), and multiple pregnancies are identified
16 weeks key milestone
antenatal appointment
discuss results
18 to 20+6 key milestone
anomaly scan
25, 28, 31, 34, 36, 38, 40, 41 and 42 weeks key milestones
monitor
additional investigations/appointments indications
Additional appointments for higher risk or complicated pregnancies
Oral glucose tolerance test in women at risk of gestational diabetes (between 24 – 28 weeks)
Anti-D injections in rhesus negative women (at 28 and 34 weeks)
Ultrasound scan at 32 weeks for women with placenta praevia on the anomaly scan
Serial growth scans are offered to women at increased risk of fetal growth restriction
what covered at routine antenatal appointments
Discuss plans for the remainder of the pregnancy and delivery
Symphysis–fundal height measurement from 24 weeks onwards
Fetal presentation assessment from 36 weeks onwards
Urine dipstick for protein for pre-eclampsia
Blood pressure for pre-eclampsia
Urine for microscopy and culture for asymptomatic bacteriuria
which vaccines pregnant women
Whooping cough (pertussis) from 16 weeks gestation
Influenza (flu) when available in autumn or winter
live vaccines c/i
what is discussed in the booking clinic (initial appointment)
What to expect at different stages of pregnancy
Lifestyle advice in pregnancy (e.g. not smoking)
Supplements (e.g. folic acid and vitamin D)
Plans for birth
Screening tests (e.g. Downs screening)
Antenatal classes
Breastfeeding classes
Discuss mental health
bloods in booking clinic
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)
HIV
Hepatitis B
Syphilis
booking clinic risk assessment
Rhesus negative (book anti-D prophylaxis)
Gestational diabetes (book oral glucose tolerance test)
Fetal growth restriction (book additional growth scans)
Venous thromboembolism (provide prophylactic LMWH if high risk)
Pre-eclampsia (provide aspirin if high risk)
1st line antenatal screening for down’s
combined test - USS and maternal blood tests
combined test results
beta-hcg (higher result..greater risk)
pregnancy associated plasma protein A (lower result…increased risk)
triple test
between 14 and 20 weeks gestation. It only involves maternal blood tests:
Beta-HCG – a higher result indicates greater risk
Alpha-fetoprotein (AFP) – a lower result indicates a greater risk
Serum oestriol (female sex hormone) – a lower result indicates a greater risk
quadruple test
between 14 and 20 weeks gestation. It is identical to the triple test, but also includes maternal blood testing for inhibin-A. A higher inhibin-A indicates a greater risk
when offered further testing after screening
greater than 1 in 150…then iffered amniocentesis or chronic villus sampling
what tests involve to confirm down’s
Chorionic villus sampling (CVS) involves an ultrasound-guided biopsy of the placental tissue. This is used when testing is done earlier in pregnancy (before 15 weeks).
Amniocentesis involves ultrasound-guided aspiration of amniotic fluid using a needle and syringe. This is used later in pregnancy once there is enough amniotic fluid to make it safer to take a sample.
other non invasive prenatal testing
Non-invasive prenatal testing (NIPT) is a relatively new test for detecting abnormalities in the fetus during pregnancy. It involves a simple blood test from the mother. The blood will contain fragments of DNA
how hypothyroidism treated in pregnancy
levothyroxine dose increased by 25-50 mcg
tx titrated based on TSH, aim for low-normal TSH level
untreated hypothyroidism complications
miscarriage, anaemia, small for gestational age and pre-eclampsia
anti-HTN drugs stopped during pregnancy
ACE inhibitors (e.g. ramipril)
Angiotensin receptor blockers (e.g. losartan)
Thiazide and thiazide-like diuretics (e.g. indapamide)
anti-HTN drugs that consider stopping in pregnancy
Labetalol (a beta-blocker – although other beta-blockers may have adverse effects)
Calcium channel blockers (e.g. nifedipine)
Alpha-blockers (e.g. doxazosin)
how epilepsy managed in pregnancy
folic acid 5mg daily from before conception to reduce the risk of neural tube defects.
Pregnancy may worsen seizure control due to the additional stress, lack of sleep, hormonal changes and altered medication regimes.
avoid sodium valporate
avoid phenytoin
anti-epileptics program pregnancy
Prevent (valproate pregnancy prevention programme)
RA during pregnancy
should be well controlled for at least three months before becoming pregnant. Often the symptoms of rheumatoid arthritis will improve during pregnancy, and may flare up after delivery
methotrexate c/i
steroids can be used in flare ups
hydroxychloroquine and sulfasalazine safe
NSAIDS pregnancy
NSAIDS are generally avoided in pregnancy unless really necessary (e.g. in rheumatoid arthritis). They are particularly avoided in the third trimester, as they can cause premature closure of the ductus arteriosus in the fetus. They can also delay labour.
beta blockers risks to unborn child
Fetal growth restriction
Hypoglycaemia in the neonate
Bradycardia in the neonate
ACEi and ARB risk to unborn baby
Oligohydramnios (reduced amniotic fluid)
Miscarriage or fetal death
Hypocalvaria (incomplete formation of the skull bones)
Renal failure in the neonate
Hypotension in the neonate
opiates risk to unborn baby
withdrawal sx after birth…neonatal abstinence syndrome…3-72 hours after birth with irritability, tachypnoea and high temp, poor feeding
warfarin risk to unborn baby
Fetal loss
Congenital malformations, particularly craniofacial problems
Bleeding during pregnancy, postpartum haemorrhage, fetal haemorrhage and intracranial bleeding
sodium valporate risk to unborn baby
neural tube defects
developmental delay
lithium risks to unborn baby
first trimester - ebstein’s anomaly (tricuspid valve lower on right side of heart…bigger RA and smaller RV)
monitor levels during pregnancy…in breastmilk is toxic to infant
SSRI risks to unborn baby
First-trimester use has a link with congenital heart defects
First-trimester use of paroxetine has a stronger link with congenital malformations
Third-trimester use has a link with persistent pulmonary hypertension in the neonate
Neonates can experience withdrawal symptoms, usually only mild and not requiring medical management
isotretinoin risks to unborn baby
highly teratogenic…miscarriage and congential defects
congenital rubella syndrome caused by
maternal infection with the rubella virus during the first 20 weeks of pregnancy
how avoid congenital rubella syndrome
planning to get pregnant - MMR vaccine and/or tested for rubella immunity
when can not give MMR vaccine
live vaccine so not during pregnancy…can have before or after
so if non immune - offered after giving birth
fx of congenital rubella syndrome
Congenital deafness
Congenital cataracts
Congenital heart disease (PDA and pulmonary stenosis)
Learning disability
chickenpox in pregnancy risks
varicella pneumonitis, hepatitis or encephalitis- in mother
Fetal varicella syndrome
Severe neonatal varicella infection (if infected around delivery)
how reduce risk chicken pox pregnancy
if had chickenpox - safe
can check IgG levels for VZV
if not immune - vaccine before or after pregnancy
can also be given IV varicella immunoglobulins as prophylaxis..within 10 days of exposure
fx of 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)
listeria pregnancy risks
listeriosis in mother - asx, flu like or can cause pneumonia or meningoencephalitis….then cause miscarriage or foetal death or severe infection
how listeria transmitted
unpasteurised dairy products, processed meat and contaminated foods…so avoid high risk foods and good hygeine
CMV infection risk to baby
congenital cytomegalovirus infection -
Fetal growth restriction
Microcephaly
Hearing loss
Vision loss
Learning disability
Seizures
how CMV spread
infected saliva or urine of asx children
toxoplasmosis risk to baby
congenital toxoplasmosis -
Intracranial calcification
Hydrocephalus
Chorioretinitis
how toxoplasma gondii spread
contamination with faeces from a cat that is a host of the parasite
parvovirus B19 infection during pregnancy risks
Miscarriage or fetal death
Severe fetal anaemia
Hydrops fetalis (fetal heart failure)
Maternal pre-eclampsia-like syndrome(aka mirror syndrome)
if suspect parvovirus infection, what tests
IgM to parvovirus, which tests for acute infection within the past four weeks
IgG to parvovirus, which tests for long term immunity to the virus after a previous infection
Rubella antibodies (as a differential diagnosis)
how mx parvovirus b19 infection in pregnancy
referral to fetal medicine to monitor
zika virus how spread
aedes mosquito