Congenital Abnormalities and Teratology

Question 1

WHO Definition of Congenital Anomaly

• Congenital anomalies comprise a wide range of abnormalities of body … or … (eg. disorders of …) that are present at …

Answer 1

• Congenital anomalies comprise a wide range of abnormalities of body structure or function (eg. disorders of metabolism) that are present at birth – i.e. occur during intra-uterine development
• Alternate terms: birth defects, clinical dysmorphologies, congenital anomaly, congenital malformation
• They result in either physical or mental disability – often both.
• Major structural anomalies account for most of the deaths, morbidity and disability related to congenital anomalies
• Minor congenital anomalies, although more prevalent among the population, are structural changes that pose no significant health problem in the neonatal period and tend to have limited social or cosmetic consequences for the affected individual.

Question 2

… structural anomalies account for most of the deaths, morbidity and disability related to congenital anomalies

Answer 2

• Major structural anomalies account for most of the deaths, morbidity and disability related to congenital anomalies

Question 4

• … congenital anomalies, although more prevalent among the population, are structural changes that pose no significant health problem in the neonatal period and tend to have limited social or cosmetic consequences for the affected individual.

Answer 4

• Minor congenital anomalies, although more prevalent among the population, are structural changes that pose no significant health problem in the neonatal period and tend to have limited social or cosmetic consequences for the affected individual.

Question 5

Congenital Abnormalities - Syndrome

Syndrome - … of congenital abnormalities caused by a … aetiology

Answer 5

Syndrome - Group of congenital abnormalities caused by a single aetiology

Question 6

Classifying Structural Abnormalities

• Malformation: …
• Disruption: …
• Deformation: …
• Dysplasia: …

Answer 6

• Malformation: flawed development of a structure or organ (eg. transposition of the great arteries)
• Disruption: alteration of an already formed organ (vascular event eg bowel atresia)
• Deformation: alteration in structure caused by extrinsic pressures (mechanical eg talipes due to reduced liquor)
• Dysplasia: abnormal organisation of cells or tissues

Question 7

4 Classifications of Structural Abnormalities are…

Answer 7

Malformation, Disruption, Deformation, Dysplasia

Question 8

Major Structural Congenital Anomalies include:

Answer 8

• Talipes equinovarus / Club foot
• Neural Tube defects: Encephalocele / Spina Bifida
• Cleft lip – various degrees

Question 9

Commonest cause of neonatal death (2015):

• … abnormalities
• …

Answer 9

• Cardiac abnormalities
• Chromosomal

Question 10

Neonatal Death - Worldwide Impact of Congenital Abnormalities

• WHO – state an estimated …. newborns die within 28-days of birth every year, worldwide, due to congenital anomalies.

Answer 10

• WHO – state an estimated 295 000 newborns die within 28-days of birth every year, worldwide, due to congenital anomalies.

Question 11

Congenital anomalies can contribute to …-… … – causing significant impacts on individuals, families, health-care systems, and societies.

Answer 11

Congenital anomalies can contribute to long-term disability – causing significant impacts on individuals, families, health-care systems, and societies.

Question 12

The most common severe congenital anomalies are … defects, … … defects and … Syndrome

Answer 12

The most common severe congenital anomalies are heart defects, neural tube defects and Downs Syndrome

Question 13

About …% of congenital anomalies = no known cause, but may be the result of one or more of the following risk factors:

Answer 13

About 50% of congenital anomalies = no known cause, but may be the result of one or more of the following risk factors:

Question 14

Chromosomal Abnormalities - Inherited Genetic Abnormalities

• … increases prevalence of rare genetic congenital anomalies
• Some ethnic communities (such as Ashkenazi Jews or Finns) have a comparatively … prevalence of rare genetic mutations

Answer 14

• Consanguinity increases prevalence of rare genetic congenital anomalies
• Some ethnic communities (such as Ashkenazi Jews or Finns) have a comparatively high prevalence of rare genetic mutations

Question 15

Consanguinity increases the prevalence of rare genetic … … and nearly … the risk for neonatal and childhood death, intellectual disability and other anomalies.

Answer 15

Consanguinity increases the prevalence of rare genetic congenital anomalies and nearly doubles the risk for neonatal and childhood death, intellectual disability and other anomalies.

Question 16

What is Consanguinity?

Answer 16

Consanguinity refers to a situation in which a couple are blood relatives (they share an ancestor).

Question 17

Chromosomal Abnormalities - Mutations during development

• … … abnormality (e.g. primary T…)

Answer 17

• Primary chromosomal abnormality (e.g. primary T21)

Question 18

Chromosomal Abnormalities - Screening

• What tests can be done?
• When?
• Who is eligible?

Answer 18

• PRE-natally in high risk patients – e.g. those with previous recurrent pregnancy loss, or family history for a particular problem
• Ante-natally - in ALL patients – through the UK AN Screening programme

Question 19

Chromosomal Abnormalities - Syndromes - Table

Answer 19

Question 20

Facial Features in Down’s Syndrome

• … nose and ,,, nasal bridge / … face
• … tongue that may …
• eyes that …
• a … back of the head / … skin

Answer 20

• small nose and flat nasal bridge / flat face
• large tongue that may stick out of mouth
• eyes that slant upwards and outwards
• a flat back of the head / thickened skin

Question 21

Other External Features in Down’s Syndrome

• … hands with … fingers
• … palmar crease
• …-average weight and length at birth

Answer 21

• broad hands with short fingers
• single palmar crease
• below-average weight and length at birth

Question 22

Other problems in Down’s Syndrome

• … defects
• duodenal …
• mild to moderate … …

Answer 22

• Cardiac defects
• duodenal atresia
• mild to moderate learning disability

Question 23

Edwards Syndrome T18 - Facial and Skeletal abnormalities:

​

Answer 23

• small, abnormally shaped head, small jaw and mouth, low-set ears, cleft lip/palate
• long fingers that overlap, with underdeveloped thumbs and clenched fists,

Question 24

In those with Edward’s Syndrome, >…% have congenital heart defects

Answer 24

Congenital heart defects: >90%

Question 25

Edward’s Syndrome - GI, Urogenital, Neurological problems

Answer 25

• Gastrointestinal abnormalities: omphalocele, oesophageal atresia ± tracheo-oesophageal fistula, umbilical or inguinal hernia, pyloric stenosis
• Urogenital abnormalities: Gonadal dysgenesis, horseshoe kidney, hydronephrosis, cystic kidneys, renal agenesis.
• Neurological problems: anencephaly, hydrocephaly and other brain malformations, severe learning disability, seizures.
• also Pulmonary hypoplasia

Question 26

Those with Edward’s Syndrome usually die within …

Answer 26

first year of life

Question 27

In those with Patau’s Syndrome, >…% have congenital heart defects

Answer 27

Congenital heart defects: >80%

Question 28

Patau’s syndrome T13 - Facial Abnormalities

Answer 28

• cleft lip / palate abnormally small eye or eyes (microphthalmia) or absence of 1 or both eyes (anophthalmia), reduced distance between the eyes (hypotelorism), microcephaly

Question 29

Patau’s syndrome T13 -GI Abnormalities

Answer 29

eg, omphalocele, exomphalos

Question 30

Patau’s Syndrome - T13 - CNS disorder

Answer 30

holoprosencephaly – single brain

Question 31

Those with Patau’s syndrome have genital abnormalities - what are the features?

Answer 31

abnormally small penis in boys,enlarged clitoris in girls

Question 32

Patau’s Syndrome - Skeletal Abnormalities

Answer 32

as extra fingers or toes (polydactyly), and a rounded bottom to the feet, known as ‘rocker-bottom’ feet

Question 33

Those with Patau’s Syndrome usually die within …

Answer 33

Usually die within days of birth

Question 34

What is a Teratogen?

Answer 34

an agent, such as a virus, a drug, or radiation, that causes malformation of an embryo or fetus.

Question 35

Common Teratogens

Answer 35

Question 36

Warfarin during Pregnancy

Answer 36

• Teratogen
• Effect:
  
  • Chondrodysplasia
  • microcephaly

Question 37

Thalidomide During Pregnancy

• What is it?
• What are the effects?

Answer 37

• Teratogen
• Effects = limb defects/heart defects

Question 38

Sodium valproate and Pregnancy

Answer 38

• epilepsy treatment
• Sodium valproate is generally not recommended in pregnancy, as it can harm your unborn baby.

Question 39

Fetal Alcohol Syndrome (FAS)

Answer 39

Foetal alcohol syndrome is a type of foetal alcohol spectrum disorder (FASD), the name for all the various problems that can affect children if their mother drinks alcohol in pregnancy.

Question 40

Thalidomide story

Answer 40

• Limbs can fail to develop properly, in some cases also eyes, ears and internal organs. No-one knows how many miscarriages the drug caused, but it’s estimated that, in Germany alone, 10,000 babies were born affected by Thalidomide. Many were too damaged to survive for long.
• Today, fewer than 3,000 are still alive. In Britain, it’s about 470

Question 41

Detecting Congenital Abnormalities

• …% detected antenatally – eg. at screening or at anomaly scan
• …% at birth – eg. due to external features or due to immediate deterioration in condition at birth
• …% 2-4 weeks
• …% after first month
  
  • (some not until adult life)

Answer 41

• 61% detected antenatally – eg. at screening or at anomaly scan
• 8% at birth – eg. due to external features or due to immediate deterioration in condition at birth
• 6% 2-4 weeks
• 18% after first month
  
  • (some not until adult life)

Question 42

Detecting Congenital Abnormalities

• …+weeks – Anencephaly, Major Limb defects
  
  • Combined screening : Nuchal translucency combined with maternal biochemistry
• … weeks (anomaly)
  
  • Heart (4 chamber view), Brain / spine, Skeletal, Cleft lip and palate, Bowel, kidneys, Movements
• … trimester
  
  • Growth, organs as per 20/40, liquor volume, movements

Answer 42

Ultrasound Scans:

• 11+weeks – Anencephaly, Major Limb defects
  
  • Combined screening : Nuchal translucency combined with maternal biochemistry
• 20 weeks (anomaly)
  
  • Heart (4 chamber view), Brain / spine, Skeletal, Cleft lip and palate, Bowel, kidneys, Movements
• Third trimester
  
  • Growth, organs as per 20/40, liquor volume, movements

Question 43

Why detect? (Congenital Abnormalities)

• 4 reasons…

Answer 43

• Termination of pregnancy
• Treatment of the condition :
  
  • Treat the baby in utero: eg. cleft palate/ pulmonary shunts / tumours, transfusions, balloon occlusion of diaphragmatic hernia
  • By maternal management: eg. Antibiotics (eg for toxoplasmosis)
  • Plan post-delivery procedures: CHD deliver in tertiary centre for immediate surgery
• Time Delivery: diabetes
• Allow time for acceptance / preparation by parents – eg. Downs group / support

Question 44

Termination of Pregnancy - What is the Abortion Act

Answer 44

• The 1967 Abortion Act renders lawful activities that would otherwise constitute a crime under the Offences Against the Person Act (OAPA) 1861. The OAPA makes it a crime for a woman to ‘procure a miscarriage’, or for another person to help her do so.
• The Abortion Act 1967 (amended by the HFEA1990) states that an abortion is legal if it is performed by a registered medical practitioner (a doctor), and that it is authorised by two doctors, acting in good faith, on one (or more) of the following grounds (with each needing to agree that at least one and the same ground is met):
• (a) that the pregnancy has not exceeded its twenty-fourth week and that the continuance of the pregnancy would involve risk, greater than if the pregnancy were terminated, of injury to the physical or mental health of the pregnant woman or any existing children of her family; or
• (b) that the termination is necessary to prevent grave permanent injury to the physical or mental health of the pregnant woman; or
• (c) that the continuance of the pregnancy would involve risk to the life of the pregnant woman, greater than if the pregnancy were terminated; or
• (d) that there is a substantial risk that if the child were born it would suffer from such physical or mental abnormalities as to be seriously handicapped.
• NB The Abortion Act did not apply to Northern Ireland until the end of 2019

Question 45

Abortion Act 1967

• There are … main categories that are the legal basis for 2 doctors to sign off a termination of pregnancy in routine practice.
• Ground C and D have a gestation limit of … weeks but the others don’t.

Answer 45

• There are 5 main categories that are the legal basis for 2 doctors to sign off a termination of pregnancy in routine practice.
• Ground C and D have a gestation limit of 24 weeks but the others don’t.

Question 46

A Doctor’s Right to Choose
Conscientious objection to participation in treatment

Answer 46

• No person shall be under any duty to participate in any treatment authorised by this Act to which he has a conscientious objection, provided that in any legal proceedings the burden of proof of conscientious objection shall rest on the person claiming to rely on it
• Nothing shall affect any duty to participate in treatment which is necessary to save the life or to prevent grave permanent injury to the physical or mental health of a pregnant woman

Question 47

Termination Processes

• Medical
  
  • Progesterone … (mifepristone) orally: stop the pregnancy
  • Followed by with … (prostagladin E1 analogue): start … contractions
  • Dependent on pregnancy gestation, this may be done at home or in the hospital
• Surgical
  
  • Tissue evacuated through … using a suction …

Answer 47

• Medical
  
  • Progesterone antagonist (mifepristone) orally: stop the pregnancy
  • Followed by with misoprostol (prostagladin E1 analogue): start uterine contractions
  • Dependent on pregnancy gestation, this may be done at home or in the hospital
• Surgical
  
  • Tissue evacuated through cervix using a suction curette

Question 48

Risks - Termination Processes

• Mortality … deaths per 100,000 abortions (no deaths in 2014 but one in 2015 and one in 2016)
• Failure: …% after surgical & …% after medical
• Incomplete abortion (…%), excessive bleeding (…%), uterine damage (surgical) (…%), infection (

Answer 48

• Mortality 0.6 deaths per 100,000 abortions (no deaths in 2014 but one in 2015 and one in 2016)
• Failure: 0.2% after surgical & 0.7% after medical
• Incomplete abortion (1%), excessive bleeding (0.1%), uterine damage (surgical) (0.5%), infection (<1%)