Pharmacology in pregnancy Flashcards
What are the main mechanisms for teratogenicity in the first trimester?
- Folate antagonism
- Neural crest disruption
- Endocrine disruption
- Oxidative stress
- Vascular disruption
What is fetotoxicity?
Toxic effect of drug on the foetus later in pregnancy
What fetotoxic effects does alcohol have?
Foetal alcohol syndrome
What fetotoxic efffect does benzodiazepines have?
Floppy infant syndrome
What are the tertogenic effects of carbemazepine?
Spina bifida/neural tube malformations
What problem can occur when using tetracyclines during lactation?
Permanent tooth staining of child
What problems can occur when using barbituates when breastfeeding?
- Lethargy
- Sedation
- Poor suck reflex
All drugs can cross the placenta apart from…
Unfractioned heparin
What drugs are used in the induction of labour?
- Prostaglandin analogues
- Oxytocin
What do prostaglandins do in induction of labour
Encourage cervical dilation and effacement - they riped the cervix.
They are inserted PV and placed in posterior fornix of vagina.
Need continuous CTG monitoring.
What does oxytocin do in the induction of labour
Initiates uteine contractions by attaching to uterine oxytocin receptors; increases the requency and force of conctractions.
This is an IV medication - short half life so wears of quickly if stopped.
Often used following prostaglandin treatment, once amniotomy performed for induction labour.
Risk of using oxytocin
Risk of uterine hypertonicity.
Can lead to hypotension and hyponatraemi - women usually have IV fluids alongside oxytocin infusion. Must monitor fluid balance.
Where is physiological oxytocin produced
- Produced by paraventricular nuclei and secreated by the posterior pituitary gland.
What is used to augment labour?
Augmentation used when contractions reduce in frequency or strength in active lbour even after spontaneous onset of labour.
Must be fully assessed before augmentation - make sure theres no malposition.
Oxytocin
Describe the active management of 3rd stage of labour
- `Early clamping (2-5 mins)
- Use of uterotonic medicaitons (pharamcological management)
- Delivery of the placenta by controlled cord traction
