J&J vaccine is being investigated regarding blood clot complications in a small number of recipients.  There is a condition called antiphospholipid syndrome aka Hughes Syndrome, that causes mini clots and spontaneous miscarriages.  It is very rare.  I have this condition.  My hypothesis is that some women with this pre-existing syndrome could be susceptible to complications.  I hope that someone who has contacts with J&J vaccine authorities could pass along my hypothesis.  

Iris L.

Certainly seems like a credible path for an expert to explore.

I have no contacts who have contacts in that field, else I would forward it on your behalf.

Spouse and FIL were scheduled to receive the J&J vaccine tomorrow evening, but it is on hold.

It is the only vaccine available in my rural area.

I will be driving back to a county hub two hours away in 10 days for my second Pfizer dose.

FIL would not be able to make that trip, unfortunately.

Apparently the authorities have already deduced that the clotting complications are an immune-modulated clotting disorder seen in young women.  Most likely males have nothing to be concerned about.  But in all cases, consultation with one's PCP is important if a person has a pre-existing clotting disorder.  

Iris