Module 9 - Maternal Medicine Flashcards
Obstetric Haemorrhage accounts for what percentage of maternal deaths?
10%
What are the levels for anaemia in pregnancy in the 1st trimester, 2nd trimester and post-partum?
The BCSH define anaemia in pregnancy as:
First trimester haemoglobin (Hb) < 110 g/l
Second/third trimester Hb < 105 g/l
Postpartum Hb < 100 g/l
How do you screen for anaemia in pregnancy?
Booking and at 28 weeks (group and screen also performed)
In multiple pregnancies additional FBC at 20-24 weeks
How do you screen for anaemia in multiple pregnancy?
Booking and at 28 weeks (group and screen also performed)
In multiple pregnancies additional FBC at 20-24 weeks
How long should you keep CTG traces for?
CTG traces should be kept for 25 years in uncomplicated delivery or indefinitely if there are concerns about future developmental delay
What is the live birth rate in women with antiphospholipid syndrome (APS) without taking medication?
10%
In women with antiphospholipid syndrome (APS) taking medication the combined use of aspirin and heparin reduces miscarriage rate by how much?
The combination of aspirin and heparin treatment reduces miscarriage rate by 54%
What is the risk of miscarriage in women aged 30-34?
15%
What is the risk of miscarriage in women aged 35-39?
25%
What is the risk of miscarriage in women aged 40-44?
51%
What is the risk of miscarriage in women aged 45 and above?
93%
What is the treatment for APS causing recurrent miscarriage?
Pregnant women with antiphospholipid syndrome should be considered for treatment with low-dose aspirin plus heparin to prevent further miscarriage
What is the most important treatable cause of recurrent miscarriage?
Antiphospholipid syndrome
How is APS diagnosed?
It is diagnosed by two positive tests (taken at least 12 weeks apart) for Lupus anticoagulant, anti-cardiolipin antibodies and anti B2 Glycoprotein I antibodies
What is the management of a single second trimester miscarriage?
1) Screen for inherited thrombophilias including factor V Leiden, factor II (prothrombin) gene mutation and protein S deficiency
2) Antiphospholipid antibodies
3) Pelvic ultrasound
What percentage of women are affected by recurrent miscarriage?
2%
What percentage of women with recurrent miscarriage have antiphospholipid antibodies?
15%
What are the antibodies tested for antiphospholipid syndrome?
1) Anticardiolipin
2) Anti-Beta-2 glycoprotein I (2GPI)
3) Lupus anticoagulant
What is the management of women with recurrent 1st trimester miscarriage?
1) Antiphospholipid antibody screen
2) Karyotype on products of conception
3) Pelvic ultrasound to exclude uterine abnormality
What is the risk of further miscarriage after three consecutive miscarriages?
40%
Risk of subsequent miscarriage increases after each miscarriage and reaches 40% after 3 consecutive pregnancy losses.
Note maternal age is another independent risk factor with worsening prognosis with advancing maternal age
Does having epilepsy make your pregnancy high risk?
Women with a history of epilepsy who are not considered to have a high risk of unprovoked seizures can be managed as low-risk women in pregnancy
What are the long-term neurodevelopmental outcomes of exposure to AEDs and maternal seizure in infants born to WWE (Women With Epilepsy)?
WWE and their partners need to be informed about the possible adverse impact on long-term neurodevelopment of the newborn following in-utero exposure to sodium valproate
There is very little evidence for levetiracetam and phenytoin
Based on limited evidence, in-utero exposure to carbamazepine and lamotrigine does not appear to adversely affect neurodevelopment of the offspring
Parents should be informed that evidence on long-term outcomes is based on small numbers of children.
How can you minimise congenital abnormalities in WWE?
1) Folic acid 5mg OD prior to conception and at least until the end of the 1st trimester to reduce the risk of congenital malformations and cognitive impairment
2) Lowest effective dose of the most appropriate AED
3) Switching from sodium valproate and avoiding AED polypharmacy. Change the medication prior to conception as recommended by an epilepsy specialist after evaluating potential risks and benefits
What is the effect of pregnancy on seizures in WWE?
1) 2/3 of WWE will not have seizure deterioration in pregnancy
2) WWE who have had a seizure in the year prior to conception need to be monitored closely
What is the risk of teratogenicity in women with epilepsy who are medicated?
6-8%
Epilepsy increases risk of teratogenicity (4% not on medication, 6-8% on treatment)
What is the risk of teratogenicity in women with epilepsy who are not medicated?
4%
Epilepsy increases risk of teratogenicity (4% not on medication, 6-8% on treatment)
What happens if a WWE unexpectedly falls pregnant?
She should be able to access an epilepsy specialist ASAP
It is never recommended to stop or switch AEDs abruptly without consultation with an epilepsy specialist
All pregnant WWE should be provided with information about the UK Epilepsy and Pregnancy Register and invited to register
What is the optimum method and timing of screening for detection of fetal abnormalities?
The fetal anomaly scan at 18+0–20+6 weeks of gestation can identify major cardiac defects in addition to neural tube defects
Should AED levels be monitored during pregnancy?
Based on current evidence, routine monitoring of serum AED levels in pregnancy is not recommended although individual circumstances may be taken into account
What are the adverse effects of AEDs in pregnancy on the mother and how can they be minimised?
Healthcare professionals should be alert to signs of depression, anxiety and any neuropsychiatric symptoms in mothers exposed to AEDs.
How should WWE be monitored in pregnancy?
Antenatally WWEs should be routinely asked about: risk factors for seizures (i.e. sleep deprivation and stress), their adherence to AEDs and seizure type and frequency
If they require admission antenatally and have a reasonable risk of seizure they should be provided with close observation by carer, partner or nursing staff
How should the fetus be monitored in pregnancy for WWE on AEDs?
Serial growth scans - 28, 32, 36/40 to detect SGA babies and to manage them appropriately
What is the role of vitamin K in preventing haemorrhagic disease of the newborn and maternal haemorrhage in WWE taking AEDs?
1) All babies born to WWE taking enzyme-inducing AEDs should be offered 1 mg of intramuscular vitamin K to prevent haemorrhagic disease of the newborn
2) There is insufficient evidence to recommend routine maternal use of oral vitamin K to prevent haemorrhagic disease of the newborn in WWE taking enzyme-inducing AEDs
3) There is insufficient evidence to recommend giving vitamin K to WWE to prevent postpartum haemorrhage
What is the optimal timing and mode of delivery for WWE based on seizure control?
WWE should be reassured that most will have an uncomplicated labour and delivery
The diagnosis of epilepsy per se is not an indication for planned caesarean section or IOL
How should women with non-epileptic attack disorder be counselled in pregnancy and how should their non-epileptic seizures be managed?
When there is a firm diagnosis of non-epileptic attack disorder these women should not be inappropriately started on AEDs or have iatrogenic early delivery
How are WWE managed during labour?
The risk of seizure in labour is low
WWE in labour should have risk factors for seizure minimised, i.e. insomnia, pain and dehydration - adequate analgesia and appropriate care is needed
AED intake should be continued during labour. If this cannot be tolerated orally, a parenteral alternative should be administered
Long-acting benzodiazepines, i.e. clobazam can be considered if there is a very high risk of seizures in the peripartum period
What is the risk of a tonic-clonic seizure during the labour and the 24 hours after birth?
1-4%
How are seizures managed in labour?
1) Every obstetric unit should have written guidelines on the management of seizures in labour
2) Stopping seizures ASAP is the priority to minimise the risk of maternal and/or fetal hypoxia and fetal acidosis. Benzodiazepines are the drug of choice
3) Continuous CTG is required for women at high risk of seizure during labour and if they have just had a seizure in labour
What are the recommended methods of analgesia in labour for WWE?
Pain management should be prioritised in WWE in labour. TENS (Transcutaneous Electrical Nerve Stimulation), Entonox and Epidural are options
Avoid Pethidine if possible and use Diamorphine instead
What is the most suitable place of delivery for WWE?
1) For WWE at risk of seizure they should be on labour ward with 1-1 midwifery care with access to maternal and fetal resuscitation
2) If the woman is not taking AEDs and has been seizure-free for a significant period of time she may have a Water Birth if deemed appropriate by an epilepsy specialist
What is the risk of seizure deterioration postpartum and how can this be minimised?
Despite the risk of seizures during and immediately after delivery are low, the risk is relatively higher than during pregnancy
WWEs need to continue to take their AEDs postnatally
WWEs need to be supported by their partners, carers, HCPs to reduce triggers and thus decrease risk of seizure, i.e. prevent sleep deprivation, pain, dehydration, stress
Is there a need to modify the dose of AED after delivery for WWE?
If the dose of AED was increased during pregnancy then this needs to be reviewed within 10 days, to prevent postpartum toxicity
What are the effects of AED exposure on the newborn from breast milk?
WWE on AEDs should be encouraged to breastfeed
WWE on AEDs should be informed that from current evidence there is no increased risk of cognitive impairment of babies exposed to breast milk with AEDs
What contraception can be safely offered to women taking AEDs?
WWE should be offered effective contraception to avoid unplanned pregnancies
Copper IUD, Mirena IUS and Depot injection are all safe and reliable options for WWE taking enzyme-inducing AEDs (Carbamazepine, Phenytoin, Phenobarbitol, Topiramate)
Hormonal contraceptives, i.e. COCP, POP, Transdermal patch, vaginal ring, Implanon may be affected by enzyme-inducing AEDs
WWE taking non-enzyme-inducing AEDs, i.e. sodium valproate (epilim), gabapentin, pregabalin, levetiracetam (keppra), clobazam, clonazepam, lamotrigine can take ALL forms of contraception
A WWE taking Carbamazepine had unprotected vaginal intercourse 3 days ago. She says her LMP was roughly two weeks ago. What form of emergency contraception do you offer her?
Copper Coil
WWE taking enzyme-inducing AEDs should be informed that a copper IUD is the preferred choice for emergency contraception
Emergency contraception pills with levonorgestrel and ulipristal acetate (EllaOne) are affected by enzyme-inducing AEDs
A WWE taking Sodium Valproate had unprotected vaginal intercourse 3 days ago. She says her LMP was roughly two weeks ago. What form of emergency contraception do you offer her?
Any form of emergency contraception - Copper IUD, Levonorgestrel, Ulipristal acetate
Emergency contraception pills with levonorgestrel and ulipristal acetate (EllaOne) are affected by enzyme-inducing AEDs. Sodium valproate is a non-enzyme-inducing AED
A WWE taking Lamotrigine presents to the Community Sexual Health Clinic enquiring about contraception. She previously had a Mirena coil and found insertion painful. Which one should she be prescribed?
Implanon or Depot injection
Women taking lamotrigine monotherapy and oestrogen-containing contraceptives should be informed of the potential increase in seizures due to a fall in the levels of lamotrigine
Lamotrigine may also have an effect on POP
Lamotrigine (antiepileptic) and griseofulvin (antifungal) are not thought to be enzyme-inducing drugs; however, contraceptive efficacy may be reduced by concurrent use. The clinical significance of this effect is unknown
What is the prevalence of epilepsy in pregnancy?
0.5-1%
Epilepsy is one of the most common neurological conditions in pregnancy, with a prevalence of 0.5–1%
What is the comparative risk of death for pregnant WWE vs non-pregnant WWE?
10x increase in risk of death
When are women considered not to have epilepsy anymore?
1) If they have gone 10 years seizure-free (with the last 5 years being off AEDs)
2) If they had childhood epilepsy syndrome and have reached adulthood seizure-free or without AEDs
Which AEDs have the lowest risk of congenital malformation to the offspring?
Lamotrigine (non-enzyme-inducing)
Carbamazepine (enzyme-inducing)
What are the most common major congenital malformations associated with AEDs?
Neural tube defects (spina bifida, anencephaly)
Congenital heart defects
Urinary tract abnormalities
Skeletal abnormalities
Cleft palate
What is the risk of recurrence of major congenital malformation in WWE who have previously had one?
16.8%
What are the definitions of Thalassaemia major, Thalassaemia intermedia and Thalassaemia carriers?
Thal major - >7 blood transfusions/year
Thal intermedia - ≤7 blood transfusions/year
Thal carrier - do not require transfusions
Beta-thalassaemia is encoded for by which chromosome?
The β-globin chains are encoded by a single gene on chromosome 11
Alpha-thalassaemia is encoded for by which chromosome?
α-globin chains are encoded by two closely linked genes on chromosome 16
What is the pathophysiology of thalassaemia syndromes?
The basic defect in thalassaemia syndromes is reduced globin chain synthesis (Hb normally made up of 2 alpha and 2 beta globin chains), the resultant RBCs have reduced Hb
Pathophysiology - ineffective erythropoiesis causes damaged RBCs and erythroid precursors which undergo extravascular haemolysis once released into the peripheral circulation
In Thalassaemia how long should pregnancy be avoided for until iron overload is controlled?
12 months
How does Thalassaemia major (homozygous beta thalassaemia) occur and what manifestations arise?
Individual inherits a defective beta globin gene from each parent. This causes a severe transfusion-dependent anaemia
How does Thalassaemia minor/trait occur and what manifestations arise?
Individual inherits one faulty thalassaemia gene. It only causes a mild-moderate microcytic anaemia with no significant detrimental effect on overall health
What are the adverse complications of multiple transfusions?
Multiple transfusions can cause iron overload, causing:
Hepatic, cardiac and endocrine dysfunction
The anterior pituitary is very sensitive to iron overload and evidence of dysfunction is common
Most of these women are subfertile due to hypogonadotrophic hypogonadism and therefore require ovulation induction therapy with gonadrotrophins to achieve pregnancy
What is the primary cause of death in 50% of cases of iron overload caused by multiple transfusions?
Cardiac failure
What are the cornerstones of modern treatment in beta thalassaemia?
Blood transfusion
Iron chelation therapy
Antenatally if women with thalassaemia major receive little or no chelation what can happen to them?
They can develop cardiomyopathy and endocrinopathies, i.e.:
- Diabetes
- Hypothyroidism
- Hypoparathyroidism
Due to the increasing iron burden
What interventions can be done prenatally to reduce the risk of morbidity for patients with thalassaemia major?
Aggressive iron chelation therapy can reduce and optimise body iron burden and reduce end-organ damage. Studies show these women are less likely to suffer with cardiomyopathies and endocrinopathies
Can iron chelation therapy be given in pregnancy?
All chelation should be regarded as teratogenic in the 1st trimester
Desferrioxamine is the only chelation agent with a body of evidence for use in the 2nd and 3rd trimester
The optimisation of iron burden is therefore critical prior to pregnancy, as iron accumulates with each blood transfusion. With the absence of chelation it may expose women to a high risk of new complications
Which endocrine condition is most common in thalassaemia: diabetes, hypothyrodisim or hypoparathyrodisim?
Diabetes
Women with diabetes should be referred to a diabetes specialist. Good glycaemic control is essential prenatally
What level of glycaemic control should diabetic women with thalassaemia have prior to conception?
Serum fructosamine levels <300 nmol/l at least 3 months before conception
This is equivalent to HbA1c <43 mmol/mol - this is associated with a reduced risk of congenital abnormalities
HbA1c is not a reliable marker of glycaemic control as it is diluted by transfused blood and can cause underestimation - so serum fructosamine is preferred for monitoring
Does thyroid function need to be checked prior to conception in thalassaemia women?
Thyroid function should be determined. The woman should be euthyroid prepregnancy
What cardiac tests should be performed prior to pregnancy in thalassaemia women?
All women should be assessed by a cardiologist with expertise in thalassaemia and/or iron overload prior to embarking on a pregnancy
They need to have had an:
1) Echo
2) ECG
3) T2 Cardiac MRI
It is important to determine how well the cardiac status of the woman will support a pregnancy as well as the severity of any iron-related cardiomyopathy. Cardiac arrhythmias are more likely in older patients who have previously had severe myocardial iron overload and are now clear of cardiac iron
What levels on T2 Cardiac MRI do you aim for in prenatal women with thalassaemia?
The aim is for no cardiac iron, but this can take years to achieve so care should be individualised to the woman
T2 Cardiac MRI >20ms is considered normal. Aim for this as it reflects minimum iron in the heart
However, pregnancies with successful maternal and fetal outcomes have occurred with lower cardiac T2 values
What T2 Cardiac MRI level is associated with an increased risk of cardiac failure with women with thalassamia?
T2 < 10 ms
A reduced ejection fraction is a relative contraindication to pregnancy and the management should be the subject of multidisciplinary discussions involving a cardiologist with experience of cardiac pathology in pregnancy, a maternal medicine specialist, a haematologist and an obstetric anaesthetist
How do you assess liver iron concentration in thalassaemia and what levels do you want pre-pregnancy?
Women should be assessed for liver iron concentration using a FerriScan® or liver T2*. Ideally the liver iron should be < 7 mg/g (dry weight) (dw)
If liver iron exceeds the target range, a period of intensive preconception chelation is required to optimise liver iron burden
For women with thalassaemia, at what level of iron at Ferriscan/T2 Liver is it advised to undergo chelation and when is it advised?
If liver iron exceeds 15 mg/g (dw) prior to conception, the risk of myocardial iron loading increases, so iron chelation with low-dose desferrioxamine should be commenced between 20 and 28 weeks under guidance from the haemoglobinopathy team
Name two common conditions caused by haemolytic anaemia in thalassaemia?
Cholelithiasis
Cholecystitis
How do you investigate for osteoporosis in thalassaemia?
All women should be offered a bone density scan to document pre-existing osteoporosis
What causes osteoporosis in thalassaemia?
Osteoporosis is a common finding in adults with thalassaemia. The pathology
is complex, but thought to be due to a variety of factors:
1) Calcium chelation by iron chelation therapy
2) Thalassaemic bone disease
3) Hypogonadism
4) Vitamin D deficiency
Most women with thalassaemia syndromes are vitamin D deficient and often osteoporotic as well. All women should have vitamin D levels optimised before pregnancy and thereafter maintained in the normal range
What is the incidence of alloimmunity in individuals with thalassaemia?
Alloimmunity occurs in 16.5% of individuals with thalassaemia.
ABO and full blood group genotype and antibody titres should be measured.
Red cell antibodies may indicate a risk of haemolytic disease of the fetus and newborn. If antibodies are present there may be challenges in obtaining suitable blood for transfusion, therefore these women should be cross-matched during labour
What medications should be reviewed preconceptually in women with thalassaemia?
Iron chelators should be reviewed and deferasirox and deferiprone ideally discontinued 3 months before conception
All bisphosphonates are contraindicated in pregnancy and should ideally be discontinued 3 months prior to conception in accordance with the product safety information sheet
What is the importance of genetic screening and what procedure(s) are involved for women with thalassaemia?
IVF and ICSI with PGD (Pre-implantation Diagnosis) should be performed in couples with thalassaemias to avoid homozygous or heterozygous pregnancy.
Preconception counselling for women with thalassaemia includes partner screening and genetic counselling as well as the methods and risks of prenatal diagnosis and termination of pregnancy.
In high-risk couples PGD is an option. If the partner is unavailable, an offer of prenatal testing is appropriate. Due to the risk of a haemoglobinopathy, potential egg and sperm donors are screened for haemoglobinopathies
Which transfusion-related infections are common in thalassaemia patients?
Hep B - Hep B vaccine should be given to all HBsAg negative women who are transfused or who may be transfused
Check Hep C status. Any woman who tests positive for Hep C needs RNA titres and to be referred to a hepatologist
Give HiB (Haemophillus influenza B) and Meningococcoal C vaccine to all women who have not had as part of their childhood vaccinations
What is the management of thalassaemia patients post-splenectomy?
Daily Penicillin prophylaxis - if allergic use erythromycin
Pneumoccoccal (Pneumovax II) vaccine every 5 years
Women who have undergone splenectomy are at risk of infection from encapsulated bacteria such as Neisseria meningitidis, Streptococcus pneumoniae and Haemophilus influenzae type b
Women should be given Haemophilus influenzae type b and the conjugated meningococcal C vaccine as a single dose if they have not received it as part of primary vaccination
What vitamin supplements are recommended in women with thalassaemia prenatally?
Folic acid (5 mg) is recommended preconceptually to all women to prevent neural tube defects
Women with thalassaemia have a much higher demand for folic acid so high-dose supplementation is needed. Folic acid 5 mg daily should be commenced 3 months prior to conception
How often should women with thalassaemia be reviewed?
4 weekly until 28/40, then 2 weekly
Women with thalassaemia should be reviewed monthly until 28 weeks of gestation and fortnightly thereafter. The multidisciplinary team should provide routine as well as specialist antenatal care
How often should women with thalassaemia and diabetes be monitored and seen antenatally?
They should have monthly serum fructosamine levels review in the specialist diabetic pregnancy clinic
When should women with thalassaemia major undergo cardiac assessment antenatally?
28 weeks
All women with thalassaemia major should undergo specialist cardiac assessment at 28 weeks of gestation and thereafter as appropriate.
Cardiac assessment is important to determine cardiac function and possible further iron chelation as well as planning for labour
When should thyroid function be measured in pregnant women with thalassaemia?
Prior to conception women should be euthyroid. Thyroid function should be monitored throughout pregnancy. If hypothyroid then the dosage of thyroxine needs to be adjusted
What is the recommended schedule of ultrasound scanning during pregnancy?
1) Early scan - 7-9/40
2) Dating scan - 11-14/40
3) Detailed anomaly scan - 18-20+6/40
4) Serial growth scans - 24, 28, 32, 36 weeks
Women with both thalassaemia and diabetes are at an increased risk of early miscarriage.
Women with thalassaemia often require IVF with ovulation induction, therefore the early stage is to determine viability of the foetus and to detect potential multiple pregnancy.
Severe maternal anaemia caused by thalassaemia can affect maternal transfer of nutrients to the fetus, and thus cause IUGR
How should the transfusion regimen be managed during pregnancy in women with thalassaemia major?
All women with thalassaemia major should be receiving blood transfusions on a regular basis aiming for a pre-transfusion haemoglobin of 100 g/l. Monitor Hb every 2-3 weeks and transfuse if Hb <100 g/l.
Give 2-3 units, and additional units a week later to cause Hb of 120 g/l.
Women with thalassaemia minor aim for the same pre-transfusion Hb of 100 g/l.
Women with thalassaemia major will already be established on transfusion regimens which generally remain stable during pregnancy.
If there is worsening maternal anaemia or evidence of IUGR, regular transfusions should be considered.
Each woman’s haemoglobin falls at different rates after transfusion so close surveillance of pretransfusion haemoglobin concentrations is required.
What Hb level is safe for delivery in women with thalassaemia?
Generally, in non-transfused patients if the Hb is >80 g/l at 36/40 then you do not need to transfuse. Transfuse after delivery
If Hb <80 g/l then transfuse 2 units at 37-38/40
What antenatal thromboprophylaxis is recommended in thalassaemia?
1) If splenectomy OR Plt >600 - Aspirin 75 mg OD
2) If splenectomy AND Plt >600 - LMWH + Aspirin 75mg OD
3) If not on LMWH then give LMWH when admitted to hospital
Women with thalassaemia major or intermedia have a prothrombotic tendency due to the presence of abnormal red cell fragments, especially if they have undergone splenectomy.
These red cell fragments combined with a high platelet count significantly increase the risk of venous thromboembolism.
This risk is highest in splenectomised women with thalassaemia intermedia who are not receiving transfusions since a good transfusion regimen suppresses endogenous erythropoiesis
What level is significant for myocardial decompensation in pregnant women with thalassaemia? How might they present?
T2 Cardiac mri <10 ms
Signs/symptoms:
1) Dyspnoea
2) Paroxysmal noctural dyspnoea
3) Orthopnoea
4) Syncope
5) Palpitations
6) Peripheral oedema
Presentation in the 1st trimester is associated with adverse clinical outcome
What is the management of pregnant thalassaemia women at highest risk of cardiac decompensation? What treatment should they start?
Desferrioxamine s.c. 20mg/kg/day for a minimum of 4-5 days a week from 20-24 weeks gestation
What is the management of pregnant thalassaemia women with liver decompensation? What treatment should they start?
Start low dose desferrioxamine from 20 weeks gestation if T2 Liver >15mg/g dw.
Aim for <15mg/g dw to reduce the risk of myocardial iron overload
What is the best intrapartum management for women with thalassaemia major or intermedia?
1) Alert haematologist, anaesthetist, obstetrician as soon as patient arrives to labour ward
2) If red cell antibodies present - X-match 2 units blood. If no atypical antibodies then G+S suffices
3) If Hb <100g/l - X-match 2 units blood
4) Women with thalassaemia major give i.v. desferroxiamine 2g over 24 hours
5) Continuous CTG whilst in labour - increased risk of operative delivery due to higher risk of fetal hypoxia
6) Active management of 3rd stage of labour
What is the postpartum VTE prophylaxis for women with thalassaemia?
There is a high risk of venous thromboembolism due to the presence of abnormal red cells in the circulation.
LWMH throughout admission
NVD - 7 days LMWH
CS - 6 weeks LMWH
Can women with thalassaemia major breastfeed whilst on desferroxiamine?
Yes.
Once initial desferrioxamine infusion 2g/24 hours is given then re-commence it s.c. It is secreted in breastmilk but not absorbed orally so there are no safety concerns with the baby
In women who do not want to breastfeed whilst on desferrioxamine then continue infusion or s.c. injections until discharge or until resumption of her usual iron chelation therapy under hematology, whichever is sooner
What is the proportion of twins of all live births?
3%
Regarding Toxoplasmosis infection, what is the risk of fetal transmission if maternal infection occurs <4 weeks gestation?
<1%
Regarding Toxoplasmosis infection, what is the risk of fetal transmission if maternal infection occurs 36 weeks gestation?
> 60%
Regarding Toxoplasmosis infection, what is the risk of fetal transmission if maternal infection occurs 13 weeks gestation?
10%
What is the rate of spontaneous abortion amongst pregnant woman infected with Rubella in the first trimester?
20%
If Rubella is contracted <11/40 what percentage of babies will have congenital rubella syndrome?
90%
If Rubella is contracted 11-16/40 what percentage of babies will have congenital rubella syndrome?
20%
Rubella causes spontaneous abortion in the first trimester in what proportion of pregnant women?
20%
What proportion of pregnancies will have congenital rubella syndrome after 20 weeks gestation?
There have been no published case reports of CRS after 20 weeks’ gestation
A patient who is 23 weeks pregnant comes to see you as there has been a recent local outbreak of Rubella and a child at a recent party had a rash. How long are patients with rubella considered infectious for?
Individuals with rubella are usually infectious from 1 week before symptoms appear to 4 days after the onset of the rash
What is the incubation period for Rubella?
14 days (same as chickenpox)
Incubation period range 12-23 days (average 14 days)
What is the treatment for pregnancies affected by Rubella?
No specific treatment. Key is prevention through vaccination programme
What is the risk of PET in this pregnancy if the previous pregnancy had severe PET, HELLP or eclampsia and delivery <34/40?
25%
What is the risk of PET in this pregnancy if the previous pregnancy had eclampsia and delivery <28/40?
55%
What is the risk of PET in this pregnancy if the previous pregnancy had PET?
Up to 16%
What is the risk of congenital CMV infection with primary CMV infection during pregnancy?
Risk of congenital infection is 30-40% with primary infection during pregnancy
What is the risk of congenital CMV infection with recurrent CMV infection in pregnancy?
Risk of congenital infection is 1-2% with recurrent CMV infection in pregnancy
What percentage of neonates with congenital CMV infection will appear asymptomatic at birth?
87%
What percentage of neonates with congenital CMV infection who are asymptomatic at birth will later develop hearing loss?
15%
When should amniocentesis be delayed for in CMV infection?
Amniocentesis should not be performed for at least 6 weeks after maternal infection and not until the 21st week of gestation
What is the incubation period for CMV?
3-12 weeks
If amniocentesis confirms CMV infection then what investigation(s) are recommended?
Cerebral MRI is indicated at 28-32 weeks of gestation
Serial ultrasound examination of the fetus should also be performed every 2-3 weeks until deliver
What is the management of pregnant women who contract Genital herpes HSV in the 1st or 2nd trimester?
Aciclovir 400mg TDS for 5 days
THEN
Aciclovir 400mg TDS from 36/40 until term to reduce the need for CS
What is the management of pregnant women who contract Genital herpes HSV in the 3rd trimester?
Aciclovir 400mg TDS from 28/40 until delivery
Will need a CS if this is the first episode
What is the incidence of neonatal HSV infection?
3 in 100,000
When is the risk of neonatal HSV infection transmission the highest?
Within 6 weeks of delivery
Highest risk with primary herpes infection within 6 weeks of delivery. Viral shedding can continue after lesions have healed
What percentage of infants with neonatal herpes have disseminated and/or central nervous system (CNS) infection?
70%
What are the types of neonatal HSV infection?
1) Skin/superifical - least severe form
2) CNS involvement - 70% neurological sequelae, 6% mortality with anti-viral treatment
3) Disseminated disease - 17% neurological sequelae, 30% mortality with anti-viral treatment
70% have disseminated and/or CNS involvement
PET leads to AKI in what proportion of cases?
1.5-2%
What level of urea in pregnancy is an indication for renal replacement therapy?
urea >17
A serum urea > 17 mmol/l despite medical management is a pregnancy-specific indicator for renal replacement therapy
AKI complicates what proportion of HELLP?
3-15%
AKI complicates 3-15% of cases of HELLP
How are women with bipolar disorder taking lithium managed?
Advise switch to Quietiapine (or other anti-psychotic)
Lithium is associated with fetal cardiac malformations and Ebstein anomaly (right ventricular outflow obstruction)
If stopping stop over 4 weeks
If continuing then measure plasma lithium levels every 4 weeks and then weekly from 36/40
What levels of Anti-D, Anti-c, Anti-E and Anti-K suggest moderate risk of HDFN and should trigger FMU referral?
Anti-D >4.0 (>15 confers severe risk of HDFN)
Anti-c >7.5 (>20 confers severe risk of HDFN)
Anti-E - if Anti-C is present
Anti-K - any level, as higher risk of HDFN
How often should MCA PSV be measured in women referred to FMU due to raised titres of antibodies?
Weekly
What level of MCA PSV should trigger invasive testing?
> 1.5x median
What is the incidence of Gestational Diabetes Insipidus?
2-4 in 100,000
What is the incidence of polyhydramnios?
1-1.5%
In regards to appendicitis in pregnancy, what is the rate of fetal loss with simple appendicitis?
1.5%
Fetal loss in simple appendicitis is 1.5%
In regards to appendicitis in pregnancy, what is the rate of fetal loss with appendicitis with peritonitis?
6%
Fetal loss in appendicitis with peritonitis 6%
In regards to appendicitis in pregnancy, what is the rate of fetal loss with a perforated appendix?
Fetal loss with perforated appendix 36%
Inherited Thrombophilia is present in what proportion of women with pregnancy associated VTE?
40%
Regarding thyroid function in pregnancy. At what gestational age do placental changes prevent significant passage of maternal thyroxine across the placenta?
12 weeks
Prior to 12 weeks gestation maternal thyroxine (fT4 not fT3) crosses the placenta. From 12 weeks placental changes prevent significant passage of maternal thyroxine and fetal thyroid function becomes independently controlled from the mother.
