Drug Use in Pregnancy Flashcards
When considering drug use in pregnancy, we need to consider 3 primary factors…
Effect of condition on pregnancy
Effect of pregnancy on the condition
Effect of drug therapy on pregnancy
Could the uncontrolled condition affect outcome of pregnancy?
Will pregnancy affect the condition?
Will drug affect the pregnancy
A teratogen is defined as…
An agent capable of producing structural or functional abnormalities in the embryo or fetus
Teratogens may cause…
Spontaneous abortion
Congenital malformations
Intrauterine growth restriction
Cognitive/behavioural effects
Carcinogenesis
Mutations
Congenital birth defects are primarily caused by…
Unknown cause
Genetic
Environmental
Drug use in pregnancy needs to consider these 3 factors…
Timing of exposure
Dose + frequency of exposure
Amount and quality of reproductive data
With preconception drug use, the all or none effect refers to…
Drug exposure in the first 15 days post-conception = spontaneous abortion
Mostly maternal use. No evidence that paternal exposure increases risk of birth defect (fertility yes)
Teratogen exposure in the first trimester is more likely to…
Cause physical malformations - most critical time for organogenesis and physical formation
Teratogen exposure in the 2nd and 3rd trimester is more likely to…
Contribute to functional + behavioral effects, growth of fetus, and CNS development
The threshold dose for many teratogens is ____, therefore as a general rule…
Not known - use the lowest effective dose for the shortest amount of time
There is little reproductive data available because…
Animal reproductive studies cannot be extrapolated to human use
Most birth defects are rare
Issues with RCT’s
Most of our reproductive drug data comes from…
Case reports
Cohort studies
Registries
Problems with epidemiological studies and pregnancy revolve around…
Recall and selection bias
No control of confounding factors
Small sample size
Ethicality
Before considering a medication in pregnancy, we should consider…
Non-pharmacological option
Gestational age
Benefit vs. risk
When selecting a drug for pregnancy, we should try to assess for the following…
Single entity available?
Published data - most effective + most reassuring safety data
Local application available?
Lowest effective dose for the shortest duration - shorter half life if possible
When counselling and managing drug therapy we should consider/assess…
How untreated disease affects pregnancy, and how pregnancy may affect disease
Baseline risk, risk vs. benefit, and other factors affecting pregnancy outcome
Preconception planning
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