In the tradition of “making up numbers and doing Fermi estimation is better than making up answers,” I would focus on the history. The frequency of past outcomes is always a good place to start (I think that’s in the Sequences somewhere) since there’s no need to consider causality, only frequency and genetic distance. An example:
Simplify and assume the cause is genetic (which will overestimate the probability; environmental or shared genetic-environmental has more randomness and will have occurrence closer to the population average). What is the total number of siblings for yourself and your spouse, including both of you, and how many stillbirths were there? Add your children to the number, including the one stillbirth, and weight those double because they’re the generation you want to know about. Calculate the percentage, then increase it by 5-10% as a crude correction for the assumption of a genetic cause. This is my estimate before you start thinking about causality.
Other things: If V is your son from a different relationship, his genetic distance is further so I would give him normal weight instead of double, but if L has other children I would still double them since the mother’s genetics are probably more important. Optionally add any of your siblings’ children, but weight them by half due to greater genetic distance. Check what percentage of stillbirths are genetic vs environmental, which could be used that to make a better correction than 5-10%. To avoid the multiple comparisons problem, make these choices before doing the analysis and commit not to change them.
Disclaimers: I am not a doctor or genetic counselor, and this is not medical advice. This is a superficial analysis written at 5am with the first few ideas I thought of, based on my unreliable intuitions about what sort of estimates might work. This sort of estimate is a lot weaker than direct evidence like the BMJ meta-analysis. I take no responsibility for any decisions that anyone makes...etc.
PS: you should probably assume the disclaimers apply to anything you read here. Also, I think another reason doctors avoid giving probabilities is that there can be legal consequences, especially if they’re misinterpreted.
If V is your son from a different relationship, his genetic distance is further so I would give him normal weight instead of double, but if L has other children I would still double them since the mother’s genetics are probably more important.
Both V and J are genetically related to L and I. Neither of us have had any other children. I’ve updated the post to make this more clear. Thank you.
My sympathies for your loss.
In the tradition of “making up numbers and doing Fermi estimation is better than making up answers,” I would focus on the history. The frequency of past outcomes is always a good place to start (I think that’s in the Sequences somewhere) since there’s no need to consider causality, only frequency and genetic distance. An example:
Simplify and assume the cause is genetic (which will overestimate the probability; environmental or shared genetic-environmental has more randomness and will have occurrence closer to the population average). What is the total number of siblings for yourself and your spouse, including both of you, and how many stillbirths were there? Add your children to the number, including the one stillbirth, and weight those double because they’re the generation you want to know about. Calculate the percentage, then increase it by 5-10% as a crude correction for the assumption of a genetic cause. This is my estimate before you start thinking about causality.
Other things: If V is your son from a different relationship, his genetic distance is further so I would give him normal weight instead of double, but if L has other children I would still double them since the mother’s genetics are probably more important. Optionally add any of your siblings’ children, but weight them by half due to greater genetic distance. Check what percentage of stillbirths are genetic vs environmental, which could be used that to make a better correction than 5-10%. To avoid the multiple comparisons problem, make these choices before doing the analysis and commit not to change them.
Disclaimers: I am not a doctor or genetic counselor, and this is not medical advice. This is a superficial analysis written at 5am with the first few ideas I thought of, based on my unreliable intuitions about what sort of estimates might work. This sort of estimate is a lot weaker than direct evidence like the BMJ meta-analysis. I take no responsibility for any decisions that anyone makes...etc.
PS: you should probably assume the disclaimers apply to anything you read here. Also, I think another reason doctors avoid giving probabilities is that there can be legal consequences, especially if they’re misinterpreted.
Both V and J are genetically related to L and I. Neither of us have had any other children. I’ve updated the post to make this more clear. Thank you.