Posting this under the heading it deserves: Pregnancy and pregnancy planning: contraindication and washout Everything below is what sits behind that.
Pregnancy and pregnancy planning: setting out the arithmetic in full, because I have had to do it twice and I would rather nobody else did.
Every step is shown. If the answer is wrong the error will be visible, which is the point of writing it out rather than posting the result.
What I want from this pregnancy and pregnancy planning thread is the list of things that would need to be true for the claim to hold. If we can write that list, we can check it.
Medullary thyroid carcinoma history: an absolute contraindication because of the preclinical findings in rodent toxicology. The history (personal or family, especially multiple endocrine neoplasia type 2) is an important screening question.
That is a description of practice, not a recommendation of it.
The version of pregnancy and pregnancy planning that I was taught turned out to be a teaching simplification. Useful, and not true in the way I had assumed it was.
One caution on pregnancy and pregnancy planning: everything above assumes the underlying documentation is what it claims to be. That assumption is doing real work and is rarely stated.
Everything in post #6 holds. The case it does not cover is the one I have.
Body weight at the extremes of the studied range affects exposure and the trials rarely reported enough to say by how much.
The interesting part of this is the exception, and I do not understand the exception.
Genetic and ancestry-related differences in response are asked about regularly and the published evidence is thin enough that the honest answer is short.
Coming back to post #6, because the follow-up matters more than the original answer.
I would keep pregnancy and pregnancy planning and the decision it usually gets used for separate in this thread. They are related and they are not the same question, and merging them is why the last one went badly.
I changed my mind about pregnancy and pregnancy planning after someone here asked me for the source and I could not produce one. That is worth saying out loud because it is the ordinary way it happens.
Post #9 answers the question as asked. The question underneath it is different.
Nothing in this subcategory is medical advice and the questions asked here are precisely the ones that need an individual assessment.
The useful distinction on pregnancy and pregnancy planning is between what was measured and what was inferred from it. Both end up in the same sentence and only one of them has error bars.
Noted, and thank you for writing it out rather than summarising it.
Post #13 is right about the mechanism and I think understates the practical bit.
Dedicated trials in under-studied populations are the only real remedy and several are ongoing, which is worth saying rather than speculating.
It reads as pedantry until the day it does not.
Answering the question post #17 raises rather than the one it answers.
Pregnancy and pregnancy planning is one of those subjects where the general answer and the answer for a specific case diverge, and the thread will go in circles until someone says which one is being asked for.
Pregnancy and planning: these compounds are not approved for use in pregnancy. Planning windows (how long to wait before attempting pregnancy) are not formally established. Conservative approaches wait several months to allow clearance.
This has been discussed before and I could not find the thread, so, again.
For anyone finding this later: the short answer on pregnancy and pregnancy planning is that it depends on one thing, and the rest of the thread is people identifying which thing.
I keep a log for pregnancy and pregnancy planning specifically because my memory of it turned out to be systematically wrong in one direction. Six weeks of notes cost nothing and settled it.
Adding the measurement that post #22 says would settle it.
Post-surgical populations, particularly after procedures affecting the gastrointestinal tract, interact with a delayed-emptying mechanism in ways that need specialist input.
On reflection I would soften that slightly.
Nothing to add, except that this is the answer I would give if asked.
Source for the pregnancy and pregnancy planning figure, since it was asked for. It is in the discussion rather than the abstract, which is why the version circulating is stronger than the paper is.
Reading the surrounding paragraph is worth the two minutes. The authors are more careful than their summarisers.
Post #25 put the caveat in the right place and I want to underline it.
I disagree with the framing of pregnancy and pregnancy planning above, and I think it is a substantive disagreement rather than a terminological one. Setting out why, so it can be checked.
The reasoning depends on an assumption that is doing a lot of work and is never stated. If the assumption holds, the conclusion follows. I do not think it holds generally.
The arithmetic in post #26 is right; the assumption feeding it is the part to check.
Extrapolating a point estimate to somebody well outside the enrolled range should be described as an extrapolation every time it is done.
Taking post #26 at face value and following it one step further.
Speaking only to pregnancy and pregnancy planning as I have actually seen it, rather than as it is usually described: the effect is real, it is smaller than the thread suggests, and the variance between people is larger than the effect.
Being outside the studied population does not mean a treatment is unsafe. It means the usual evidence is not available and the reasoning has to be explicit.