Connie

I agree with your doctor that hormonal changes can make a huge difference in pelvic relaxation/prolapse, but I really do not think quitting breastfeeding is necessary. The idea is to get some estrogen back (breastfeeding suppresses that,) but it is very simple to give some vaginal estrogen cream and continue to breastfeed. There is a theoretical risk that your milk supply could be decreased by doing that, but that is unlikely after you have been established breastfeeding this long. You might ask your doc if they would be willing to try that. (FYI, the traditional Chinese medicine remedy for prolapse is astragalus, though there is minimal research for this indication. It is mostly studied for immune support. I like to recommend cooking with astragalus to prevent infections and keep your family well, so you might think about that for this situation in hopes of a two-fer.)

As for breastfeeding benefits, there is a great website that has collected a lot of the relevant articles at Linkages Project. There is some
additional benefit for the child in continuing to breastfeed in the second 6 months of life, and every additional 6 months you breastfeed also provides you with increased protection from breast cancer. I do recommend weaning by around age 2 if your daughter has not decided to do it on her own, just for behavioral reasons.

Connie

There are 2 issues:
1. Your child being affected by the amount of radiation coming from your body. This is pretty small, though highest in the first few days after treatment.
2. Your child being affected by ingested I-131, which will go straight to his thyroid. I think this is where the concern is. Your urine, sweat, saliva, tears, etc. will contain this, so any surface you contaminate could be a danger if he gets those secretions in his mouth somehow.

The half-life of the iodine itself is 8 days, and we usually talk about 4-5 half-lives to really clear (the remaining amount after 4 half-lives is about 6%, after 5 is about 3%) but the half-life in your body is much shorter because your body actively excretes it. For the standard person receiving RAI who has no thyroid tissue, the vast majority of the dose is gone in 3-5 days. If there is tumor tissue that holds onto the radiation, it can stick around longer – supposedly you can set off radiation alarms in airports for up to 3 months. . . They will almost certainly do a scan after you get the RAI, and you will be able to tell from that whether it is hanging on somewhere in your body. Mine stuck around in one of my ovaries, for reasons no one can figure out. . . .

I will also say I am completely on the paranoid end of the spectrum (afraid of plastic containers, non-organic foods, etc. for my kid,) so take what I say with a grain of salt, but I think staying a good distance away for at least 3 days, ideally a week (not even lap-sitting) makes sense, but then physical contact like hugging should really not be an issue unless there is residual tumor. Still, being cautious of surfaces you may have contaminated (your bathroom, sink knobs, etc.) for a few weeks is prudent. My concern about sharing the bed would be more the drool, and less the contact, but it would be great if your partner could sleep between you and your son, and maybe to wash the pillowcase daily. . .

As far as I could tell, no one has ever done surveillance on family members of people treated with I-131 for thyroid cancer to see if their family members develop more thyroid cancer down the road, but when I was on the online support group I participated in around the time of my treatment I met two other patients whose parents had been treated for ThyCa.

Connie