Antenatal Care and Screening Flashcards

Question

Describe non-invasive prenatal testing as an additional form of testing after high risk chromosomal abnormality is identified?

Answer 1

* Non-invasive prenatal testing * Maternal blood taken to detect foetal cell free DNA and look for chromosomal trisomy * Not offered on NHS

Answer 2

Increased risk

Answer 3

2-3% of all births, increasing due to assisted conception

Answer 4

Palpitations

Answer 5

In the second trimester Expansion of the uteroplacental circulation A fall in systemic vascular resistance A reduction in blood viscosity A reduction in sensitivity to angiotensin BP usually returns to normal in the third trimester

Answer 6

Increased urine output Renal plasma flow increases by 25-50% Glomerular Filtration Rate increases by 50% Serum urea and creatinine decrease

Answer 7

There is an increase in urinary stasis Hydronephrosis is physiological in the third trimester and makes pyelonephritis more common Can be associated with preterm labour so important to treat Bladder capacity is reduced in the third trimester because of pressure in the pelvis from the expanding uterus Decreased serum urea and creatinine partly due to increased GFR but partly due to dilutional effect of increased plasma volume Easier path for ascending infection and increased pyelonephritis. Caution with UTI in pregnancy as increases the incidence of PTL therefore low threshold for MSSU and antibiotics if +ve

Answer 8

Plasma volume increases by about 50% and RBC mass by about 25% This results in a drop in haemoglobin by dilution from 133-121g/L Iron requirements are increased by 1g during pregnancy WBC increase slightly to 9000-12000/mL Platelet count falls by dilution

Answer 9

•Progesterone acts centrally to reduce CO2 Increased Tidal volume Increased Respiratory rate Increased Plasma pH * O2 consumption by increased 20% * Plasma PO2 is unchanged * Hyperaemia of respiratory mucous membranes

Answer 10

* Oesophageal peristalsis is reduced * Gastric emptying slows * Cardiac sphincter relaxes * GI motility is reduced due to Increase progesterone and decrease motilin

Answer 11

Ideally for all women In Scotland, a third of pregnancies are unplanned

Answer 12

All women This can be done in primary care General health measures Improve diet Optimise BMI Reduce alcohol consumption Smoking cessation advice Folic acid 400 mcg standard dose or 5mg high dose Vitamin D 10mcg daily

Answer 13

Obesity has a detrimental affect on pregnancy with a higher rate of poor outcomes including miscarriage and still birth. It also affects the function of the uterus in labour. Routine measurements of fundal height to monitor fetal growth and presentation may be impossible on abdominal palpation. Venous thromboembolic events are more common in obese patients.

Answer 14

Fetal abnormalities causing a fetal alcohol syndrome which produces a typical facial appearance and affects learning, the routine advice given to pregnant women is to avoid alcohol although there is no evidence of harm from minimal alcohol consumption during pregnancy

Answer 15

Pregnancy outcomes are poorer at both ends of the fertile population. Teenagers may be socially deprived with lack of support, smoke more, and not receive the antenatal care they need, often booking late. Older women, particularly the over 40s, are more prone to pre-existing medical conditions and develop complications of pregnancy such as gestational diabetes and hypertension. Chromosomal disorders increase dramatically with advancing maternal age.

Answer 16

Pre-eclampsia is predominantly a condition of nulliparity, occurring in the first pregnancy. Grand multiparity (4 or more deliveries) predisposes women to postpartum haemorrhage.

Answer 17

A patient’s occupation may expose them to situations that put either themselves or their fetus at risk. They may have a very busy job with inadequate rest periods or be exposed to substances such as chemicals which cause fetal anomalies.

Answer 18

Substance misuse such has effects both on the mother who may not seek antenatal care or attend intermittently and on the fetus. Heroin, methadone and benziodiazapines are addictive to the fetus and cause a withdrawal syndrome in the baby when it is cut off from its supply at birth. Cocaine and crack are associated with abruption resulting in fetal death. Women with substance misuse are seen in a specialist multidisciplinary clinic involving obstetricians, midwives, members of the substance misuse team (psychiatrists & CPNs), social workers and health visitors.

Answer 19

Higher dose if had issues like spina bifida in previous births Vit D is now recommended for all women during pregnancy too

Answer 20

Optimise maternal health Psychiatric health is important Stop/Change any unsuitable drugs Advise regarding complications associated with maternal medical problems Occasionally advise against pregnancy

Answer 21

Inborn error of protein metabolism which causes an inability to metabolism essential amnio acid phenylalanine. This results in high levels which causes mental developmental impairment. It is screened for in newborn babies and amendable to treatment. However if a woman with PKU is pregnant she needs to restart her low phenylalanine diet to prevent high levels reaching the developing fetal brain.

Answer 22

Hypothyroidism These women take thyroxine. The demand for thyroxine increases during pregnancy and therefore doses may need to be increased. Normal thyroxine levels are also required for fetal brain development.

Answer 23

They need treatment to keep their thyroid hormone levels normal. Thyroid stimulating antibodies can cross the placenta to the fetus so the neonate will need to be checked as well.

Answer 24

Require additional care in relation to pregnancy. Ideally their glucose control is optimised prior to conception as high blood glucose levels are associated with congenital anomalies. Women with type 2 diabetes who are on oral hypoglyceamic medications need to be switched to insulin. Diabetic patients are more at risk of pregnancy complications such as pre-eclampsia, stillbirth and macrosomic infants. They should be cared for in a joint diabetic obstetric antenatal clinic.

Answer 25

Renal patients are more likely to develop pre-eclampsia which may be difficult to diagnose if they already have proteinuria and pre-existing hypertension. Pregnancy is now possible for women who previously would not have been able to have children. Renal transplantation restores fertility as well as renal function

Answer 26

The main concern for women with epilepsy is the effect of their anti-epileptic medication on their developing fetus. Sodium valproate is an effective drug but is associated with a higher rate of spina bifida in the offspring of women taking it.

Answer 27

Counsel regarding risk of recurrence Caesarean Section DVT Pre-eclampsia Actions to reduce risk of recurrence Thromboprophylaxis Low dose aspirin

Answer 28

Counsel regarding risk of recurrence Pre-term delivery Intrauterine growth restriction Fetal abnormality Actions to reduce risk of recurrence Treatment of infection High dose folic acid Low dose aspiri

Answer 29

If a patient previously had a caesarean section it is necessary to determine the safest mode of delivery on this occasion. Usually if she has only had one caesarean for a non-recurring cause such as breech presentation she will be fine to undertake a trial of labour. However after 2 previous caesareans it is customary to deliver by elective caesarean again.

Answer 30

High quality antenatal care reduces fetal and maternal mortality Aims to identify problems Mother Problems such as pre-exisiting or developing illness ‘minor’ problems of pregnancy such as anaemia Fetus Small for gestational age Fetal abnormality Social Support Domestic violence Psychiatric Illness

Answer 31

Routine enquiry Feeling well Feeling fetal movements (after 20 weeks) Blood Pressure Detect evolving hypertension Urinalysis Abdominal Palpation Determine fetal presetnation Listen to fetal heart

Answer 32

Assess symphyseal fundal height (SFH) Estimate size of baby Estimate liquor volume

Answer 33

Has implications for delivery Some abnormal lies are secondary to problems such as placenta praevia which can have serious consequences around he time of delivery and are important to detect Check the measurementrs are progressing normal. May not be possible maybe due to their BMI or other issues

Answer 34

Screening is the testing of a symptomless population in order to detect cases of a disease at an early stage and a variety of screening tests are offered to pregnant women Women should be offered but not compulsory- Should get appropriate councelling but do not have to accept the screening

Answer 35

Hepatitis B- If infected can provide passive and active immunisation for baby Syphilis- Easily treated with Penicillin HIV- Maternal treatment and careful planning reduces vertical transmission MSSU- Urinary tract infection All pregnant women are screened for Rubella, Hepatitis B, Syphilis, and HIV as part of routine ANC

Answer 36

12 and 28 weeks gestation

Answer 37

nRhesus disease is a condition where antibodies in a pregnant woman's blood destroy her baby's blood cells. It's also known as haemolytic disease of the foetus and newborn (HDFN). Rhesus disease doesn't harm the mother, but it can cause the baby to become anaemic and develop jaundice.

Answer 38

Screen for it by routine full blood counts at booking and 28/40 gestation. Additional iron is required to make extra maternal red blood cells as normal adaptation of pregnancy and needed by the developing fetus and placenta. If her iron stores are low prior to pregnancy she may well become iron deficient during pregnancy. Once detected this can be remedied by taking iron tablets.

Answer 39

Isoimmunisation refers to the development of antibodies against blood groups. The commonest isoimmunisation is Rhesus disease where anti-D antibodies occur. If a Rhesus negative women is carrying a rhesus positive baby she will develop anti D antibodies if the fetal red blood cells enter the maternal circulation. This occurs with miscarriage beyond 12 weeks gestation, surgical or medical evacuation of the uterus either due to miscarriage or termination, ectopic pregnancy, antepartum haemorrhage and at delivery. Therefore the antibodies tend to develop following the first pregnancy. In subsequent pregnancies with a Rhesus positive fetus the anti-D antibodies cross the placenta and lead to destruction of the fetal red blood cells causing fetal anaemia. Which can result in fetal death. Screening pregnant women allows us to identify women at risk ie Rhesus negative and provide them with passive immunisation to destroy fetal RBCs in the maternal circulation before the maternal immune system has the opportunity to be activated and produce its own antibodies. It also identifies those women with pre-existing antibodies so that those pregnancies can be monitored more closely to detect the development of fetal anaemia and provide treatment. Anti D IgG is offered to all Rh negative women both prophylactically and after potentially sensitising events.

Answer 40

Ensure pregnancy viable Multiple pregnancy Identify abnormalities incompatible with life Offer and carry out Down’s syndrome screening

Answer 41

nSystematic structural review of baby nNot possible to identify all problems nCan identify problems that need intrauterine or postnatal treatment

Answer 42

A rugby ball

Answer 43

Anacephaly

Answer 44

Trisomy 13, 18 and 21 Multiple screening tests are available Women and their partners must be aware prior to any screening taking place that tests for fetal abnormality only provide a risk of their baby being affected. Further testing will be offered to definitively tell if a baby is affected Embarking on prenatal screening may sometimes result in parents having to make a difficult decision regarding termination of pregnancy

Answer 45

Carried out at 10-14 weeks gestation Uses maternal risk factors, serum b-human chorionic gonadotrophin (b-hCG) and pregnancy associated plasma protein A (PAPP-A) and fetal nuchal translucency (NT) measurement Detection rate for Trisomy 21 of ~90%, invasive testing rate of 5%

Answer 46

NT measurements are taken between Crown Rump Length’s of 45-84mm

Answer 47

Increases with gestational age and the incidence of chromosomal and other abnormalities is related to the size, rather than the appearance of NT.

Answer 48

Further testing is offered if risk of Down’s syndrome is \>1 in 150 Options: * CVS * Amniocentesis * Non-invasive Prenatal testing

Answer 49

nMaternal blood taken nCan detect fetal cell free DNA released from the placenta nNo risk of miscarriage nNot diagnostic, so if gives a high risk result, parents are offered CVS/amniocentesis

Answer 50

Between 10-14 weeks 1-2% risk of miscarriage

Answer 51

15 weeks onwards ~1% risk of miscarriage

Answer 52

Not routinely offered since introduction of first trimester screening Personal or family history of NTD are at increased risk Should be advised to take 5mg folic acid to reduce risk First trimester ultrasound to detect anencephaly and sometimes spina bifida (variants of NTD) Second trimester biochemical screening- Carried out if not able to get NT measurement. Maternal serum is tested for alpha fetoprotein. \>2.0MoM is high risk and warrants investigation Second trimester (20wk) ultrasound will detect \>90% of NTD

Answer 53

Performed with the purpose of detecting fetal abnormality This is a good screening test for major structural abnormalities but a poor test for chromosomal abnormalities as * 50% of fetuses with T21 will have a normal detailed USS * 17% of fetuses with T18 will have a normal detailed USS * 9% of fetuses with T13 will have a normal detailed USS

Answer 54

Checks hearbeat, stage, confirms number of babies, gives nuchal transulency measurement

Answer 55

Projection of placental tissue into the interfetal membrane. In monochorionic pregnancies, there is no tissue seen and this is known as a T-sign