Routine antenatal care Flashcards

Question

Omega 3 fatty aid

Answer 1

2-3 serves (150g per serve) of fish per week More not recommended as concern about intake of pollutants (mercury) If low dietary intake (e.g. minimal seafood), consider supplement Important building blocks for the developing fetal brain and retina No conclusive evidence of benefit using fish oil supplementation in pregnancy is confirmed

Answer 2

Physical benefits - fitness, prevention of excessive weight gain, lifelong benefits (reduced CVD, T2DM, some cancers) Psychological wellbeing - reduced Sx of depression No evidence detrimental to fetus or woman Regular exercise during pregnancy has been a/w shorter and less complicated labour, and fewer neonatal complications (but inconclusive evidence) Active (30 mins) on most, preferably all days each week Strengthening exercise 2x a week No heavy lifting or lying on back after 1st trimester Active on most, preferably all days each week - E.g. ligament laxity, increase in metabolic rate - avoid exercising at high temperatures and humidity, increased loading at the joints with weight change

Answer 3

``` FBC Blood group and antibody screen Rubella antibody status Syphilis serology HIV Hepatitis B serology Hepatitis C serology ``` Varicella (Au) HbA1c (NZ) Others to consider - Screening for haemoglobinopathies (low MCV) - CMV (pending job) - TSH (T1DM) Maternal Mental Health Screening Family violence

Answer 4

Lack of high-level evidence on routine surveillance between 41 and 42/40 Advise women to be vigilant of a change in fetal movements From 41/40, may be reasonable to offer twice weekly CTG and USS to assess AFI for surveillance of fetal wellbeing (RANZCOG) Detailed and frequent assessment of fetal wellbeing, including liquor volume, is strongly recommended in pregnancies at or beyond 42/40

Answer 5

The detection of carrier status of autosomal and x-linked recessive diseases in couples or people who do not have an a priori increased chance of being a carrier based on their or their partners' personal or family history - Does not refer to testing an individual with a strong FHx Most common inherited conditions for which prenatal diagnosis is currently performed: - Thalassaemia - Cystic fibrosis - Fragile X syndrome

Answer 6

1. Having child and testing after birth 2. Conceiving naturally and having diagnostic testing during pregnancy (amniocentesis or CVS) 3. IVF and testing embryos by preimplantation genetic diagnosis 4. Using donor sperm, egg or embryo from unaffected individuals 5. Adoption 6. Not having children

Answer 7

FHx to identify relatives with heritable genetic disorders, or presence of consanguinity - If positive, offer referral to a genetic counselling Basic screening for thalassaemic carrier status - FBC - Screening with specific assays for haemoglobinopathies should be considered in high probability ethnic or population groups Offer information on carrier screening for other genetic conditions to all women planning pregnancy or in the first trimester - Panel for a limited selection of the most frequent conditions (e.g. CF, spinal muscular atrophy, fragile X syndrome) - Expanded carrier screening - identifies max no. of carrier, but identifying variants of uncertain significance. Should have robust counselling options if this is chosen Screening will not identify carrier status for all mutations Risk of identifying the individual tested as affected by one of the conditions screened for

Answer 8

Sequential screening (two step) - One member of the couple is screen, and the second only screened if the first member is a carrier Advantages: - Reduces overall cost for most couples - Allows for cascade testing of relatives of carriers Couple screening (one step) - Both members screened at the same time - May or may not be informed of the individual results of carrier testing Advantages: - Faster - Far fewer individuals/couples require genetic counselling - Anxiety from waiting for the partner result is minimised Disadvantages: - Test costs are higher -Opportunity for cascade testing is largely lost - Results become invalid if they change reproductive partners in future pregnancies

Answer 9

Cystic fibrosis - 1 in 35 - 1 in 4900 Spinal muscular atrophy (severe muscle weakness, death usually during childhood) - 1 in 50 - 1 in 9900 Fragile X syndrome (intellectual disability, autism ) - 1 in 330 - 1 in 7100

Answer 10

Prenatal knowledge of the presence of conditions allows: - Changes to the management of the pregnancy to permit delivery in an appropriate location - Rapid access to neonatal treatment - Appropriate antenatal care - Option of abortion - Can help couple prepare

Answer 11

11+0 to 13+6 Maternal age USS assessment of nuchal translucency - Additional markers of aneuploidy - improve detection rates to 96% and lower false positive rate to 2.5% - nasal bone, ductus venosus waveform, tricuspid valve flow Maternal serum markers - Pregnancy-associated plasma protein A (PAPP-A) - product of the placenta and decidua - Beta human chorionic gonadotropin (beta HCG)

Answer 12

With 1 in 300 cut off for trisomy 21, 13 and 18 Sensitivity 85% Specificity 95% PPV ~7-10% Additional advantages of USS at this gestation: - Confirm fetal number, gestation, viability, structural development

Answer 13

>10/40 DNA sequencing or array based technology to detect aneuploidy in placenta tissues by measuring cfDNA in maternal plasma Adequate fraction 3-4% of total maternal cfDNA cfDNA is cleared rapidly after birth, therefore specific to current pregnancy Works by sequencing a portion of each DNA fragment in maternal plasma (both maternal and fetal) Counting the number of fragments arising from each chromosome - If trisomy in fetus, then extra sequences will map to chromosome 21, 18 or 13

Answer 14

A primary screening test for fetal aneuploidy A secondary screen for women with an increased risk result on a primary screening test, who do not want diagnostic testing Any woman with probability below the traditional threshold for offering diagnostic testing but who wishes to self-fund further testing

Answer 15

Highest sensitivity and specificity of all screening tests for Down syndrome - sensitivity and specificity - 99% - PPV 45% Lower false positive rate - Therefore fewer invasive procedures Risk assessment is less dependent of gestational age cfDNA is cleared rapidly after birth, therefore specific to current pregnancy Not confounded by smoking or IVF Allows for detection of sex chromosomal conditions LIMITATIONS - Not funded - Unable to provide result in 1-6% - Maternal weight can affect technical performance - Does not have sufficient diagnostic accuracy to replace invasive testing - False positives - occur in approx 0.3% - still need USS for structural assessment - risk of findings maternal abnormalities

Answer 16

15+0 to 20+0 weeks ``` Maternal age Maternal serum markers: - Alpha-fetoprotein - Beta HCG - Unconjugated estriol - Inhibin A ``` Sensitivity 70-75% Specificity 93% PPV ~2-3%

Answer 17

Maternal weight Smoking IVF - Pregnancies conceived using ART have low levels of PAPP-A --> increased likelihood of receiving false positive results - Higher risk of cfDNA test failure for IVF pregnancies compared with spontaneous conceptions (5.2% vs. 2.2%) Particularly affect the level of serum markers

Answer 18

Nuchal translucency (ASUM): - Perform 11+0 - 13+6 - CRL 45-84mm Abnormal if >3-3.5mm but correlate with GA

Answer 19

Affect 2-3.5% of all pregnancies Offer USS assessment to all patients in the mid trimester (18-22/40) - While up to 50% of major conditions may be identifiable in the first trimester, many cases will require second trimester review to clarify diagnosis and / or prognosis

Answer 20

Fetal loss rate may be as low as 1 in 900 - No difference between CVS and amniocentesis - operator and experience-dependent ``` Sepsis Bowel injury Fetal injury Placental mosaicism (in CVS) Anti D if Rh(D) neg Haematoma ``` Even a 'diagnostic test' is not a test for every disease and a normal result does not exclude the chance of the baby having a chromosomal or genetic disease

Answer 21

Percutaneous transabdominal puncture of the uterus during pregnancy to obtain amniotic fluid From 15/40 Optimal timing 15+0 to 17+6 Cells shed from the amnion and the lower fetal urinary tract Should not be performed before 15/40 because of the increased risk of adverse outcomes such as talipes ? respiratory morbidity

Answer 22

Sampling of the placental chorionic villi 11 to 14 weeks Although CVS can be performed >14/40, amniocentesis is preferred from 15/40 as technically easier, more comfortable for patient and avoids placental mosaicism Transabdominal or transcervical >5mg of villus tissue required Prior to 11/40, CVS a/w increased risk of limb reduction defects Placenta location (posterior) may not be accessible

Answer 23

Confined placental mosaicism = a discrepancy between the genotype of the placenta and the genotype of the fetus CVS has a higher risk of confined placental mosaicism than amniocentesis (2.3 versus 0.4 %) Mosaicism on CVS has both diagnostic and prognostic implications because placental function can be affected, leading to miscarriage, fetal growth restriction, fetal death, or stillbirth Identified in 1-2% of CVS samples, but confirmed in the fetus in only 11-13%

Answer 24

Conventional karyotyping Rapid aneuploidy tests - FISH - Can use for diagnosis of specific microdeletion syndromes Chromosomal microarray analysis - Detects significantly more aneuploidies than conventional karyotype following structural fetal condition identification on USS, therefore 1st line

Answer 25

ADEC Classification A Well controlled trials have shown no teratogenicity B1 Limited number of women with no problems, animals OK B2 As B1 though animal studies inadequate B3 As B2 though animal studies show increased risk C May cause effects but no malformation D ? Increased malformations X Should not be used in pregnancy

Answer 26

an incident of threatening behaviour, violence or abuse (psychological, physical, sexual, financial or emotional) between adults (>16y) who are or have been intimate partners or family members

Answer 27

4-9% of women experience domestic abuse during pregnancy or after birth ~30% of domestic abuse starts in pregnancy (UK) Pregnancy is time when DA is known to increase Prevalence of domestic abuse is increased amongst: - Women <24y - Women who are divorced - Those with a long-term illness or disability - Those in the lowest household income brackets

Answer 28

A women who is a victim of domestic abuse if more likely to: - Book late or have a concealed pregnancy - Be a teenager - Have bleeding in early pregnancy - Experience preterm labour - Develop chorioamnionitis - Have a low birth weight baby - Have an unexplained stillbirth - Suffer from perinatal depression, anxiety and PTSD

Answer 29

The maternal sensation of any discrete kick, flutter, swish or roll Provides an indication of the integrity of the CNS and musculoskeletal system

Answer 30

Perception of FM usually from 16-20/40 - From 16/40 for multip, 18-20 weeks for primip There is diurnal changes in fetal movements Periods of activity and also of rest and sleep - Sleep cycles usually 20-40 mins, rarely exceed 90 mins in a healthy fetus Afternoon and evening periods are the peak of activity The number of spontaneous FMs increase and then tend to plateau at 32/40, but there is no reduction - Evidence does not support that the number of FM decreases as pregnancy advances or prior to the onset of labour - Type of movements may change Correlation between maternal perception of FM and FM concurrently detected on USS show wide variation - 37-88%

Answer 31

No universally agreed definition RFM is linked to adverse perinatal outcomes, such as: - Neurodevelopmental disability - Infection - Feto-maternal haemorrhage - Emergency delivery - Umbilical cord complications - SGA - FGR The majority of women (55%) experiencing a stillbirth perceived a reduction in FM prior to diagnosis

Answer 32

All pregnant women should be routinely provided with verbal and written information regarding normal FM during the antenatal period - Include info on the changing patterns of movement as the fetus develops, normal wake / sleep cycles and factors which may modify perception of FM (e.g. high BMI, placental position) If women are unsure whether FM are reduced after 28+0, they should be advised to lie on their left side and focus on FM for 2h. If FM abnormal, they should contact their midwife or maternity unit immediately There is insufficient evidence to recommend formal fetal movement counting using specified alarm limits to reduce adverse outcomes

Answer 33

Should happen within 2h Assess for risk factors a/w stillbirth Review fundal height, abdo exam (uterine tone, tenderness), maternal HR and BP, temp CTG USS for fetal biometry and AFV should be considered -Timeframe guided by clinical circumstances - preferably within 24h Consider Kleihauer

Answer 34

``` Previous stillbirth Previous PTB with SGA FGR Previous reporting of DFM BMI >25 Smoking AMA IVF Parity of 0 or >/=3 Pre-existing diabetes APH Indigenous ethnicity Low SES Maternal conditions Obstetric cholestasis ```

Answer 35

stepped wedge, cluster-randomised trial Education package for patients and staff, CTG within 2h, growth within 24h IOL from 37/40 if SGA or persistent RFM Package of interventions did not reduce the incidence of stillbirth The intervention increased the frequency of IOL and birth by CS and prolonged NICU admission period

Answer 36

Most domestic airlines will not permit pregnant women to travel for >4 hours after 36 weeks gestation International flights restrict travel from 32 weeks Consider VTE risk