Pregnancy Flashcards
What are neural tube defects?
When the neural tube (forming the early brain and spine) doesn’t close properly
When do neural tube defects occur?
Early in the pregnancy, often before a woman knows she is pregnant.
What are the 2 most common NTDs?
Spina bifida and Anencephaly
What is spina bifida?
An NTD which causes physical and intellectual disabilities that vary in severity depending on the size and location of the opening of the spine, and whether the spinal cord and nerves are affected
What is anencephaly?
A NTD where the upper part of the neural tube does not close all the way, resulting in the baby being born without parts of the skull and brain. Usually, the baby will die shortly after birth.
What makes a couple higher risk of NTD?
A previous pregnancy being affected by NTD
Family or personal history of NTD
Woman taking anti-epileptocs
Woman having diabetes, sickle cell anaemia, or thalassaemia.
The woman being obese (BMI >30)
What role does folate play in pregnancy?
Folate is an essential water soluble B vitamin which serves as a cofactor in cell division. Deficiency can affect expression of neural tube closure-related genes and impair growth and replication within the foetus.
Name 5 foods high in folate?
Leafy greens
Fruits
Beans
Meat
Cerals
How should women take folic acid supplements for pregnancy?
Women should take folic acid daily before conception and until the 12th week.
Low risk: 400mcg
High risk: 5mg
When does nausea and vomiting occur throughout pregnancy?
Begins 4-7th week
Peaks between 9-16th week
Resolves before 16-20th week
When does it mean if nausea and vomiting in pregnancy begins after 11 weeks?
Likely not morning sickness, due to another cause.
What is some lifestyle advice for morning sickness?
Rest - tiredness makes nausea worse.
Avoid trigger foods/smells.
Eat dry toast or plain biscuit or similar before getting out of bef.
Eat small, frequent, protein-rich meals.
Sip water little and often.
Cold foods tend to be better tolerated if nausea is smell-related.
Ginger supplements, teas, or foods may reduce symptoms.
Try acupressure bracelets.
What are some first line pharmacological options for morning sickness?
Xonvea
Chlorpromazine
Cyclizine
Prochlorperazine
Promethazine
What is Xonvea?
The only medicine specifically licensed in the UK for nausea and vomiting. Contains doxylamine/pyridoxine.
What is doxylamine?
A H1 receptor antagonist (1st generation antihistamine)
What is chlorpromazine?
A phenothiazine anti-emetic which blocks histamine H1, dopamine D2, and muscarinic M1 receptors in the vomiting centre.
What is cyclizine?
Antihistamine and anti-emetic which blocks histamine H1 and has anti-muscarinic effects at the chemoreceptor trigger zone of the vomiting centre.
How does metoclopramide work?
Inhibits dopamine and serotonin in the chemoreceptor trigger zone.
What is prochlorperazine?
A phenothiazine anti-emetic which inhibits dopaminergic receptors.
What is promethazine?
An antihistamine and anti-emetic which inhibits histaminic, muscarinic, and dopaminergic receptors in the vomiting centre.
How does ondansetron work?
Inhibits serotonin/5HT3 receptors.
Which anti-emetics are not recommended in the 3rd trimester and why?
Chlorpromazine, Prochlorperazine - EPSE’s and withdrawal.
Cyclizine, Promethazine - paradoxical excitability and tremor
Metoclopramide - EPSEs
How long should metoclopramide be used for?
Not recommended for use over 5 days due to EPSEs
Should ondansetron be used in pregnancy?
Not licensed but used for severe nausea and vomiting. Associated with increased risk of cleft lip/palate during first trimester.
What can be used in moderate-severe nausea and vomiting in pregnancy?
IV fluids
Acupressure
Oral prednisolone 40-50mg (BP monitor and diabetes screen)
What is very severe morning sickness known as?
Hyperemesis gravidarum