It's my diagnosis and I have looked it up quite a bit because I like to understand things about myself.
It's something you're born with but the effects don't necessarily start straight away. In my case I have had Raynaud's since I was a child, I have had TIAs since going on the pill (bit of a d'uh when you look back! It was therapeutic use and we didn't know what was happening, just assumed I fainted a lot) at the age of 13, although looking at photos I think something happened earlier than that as my face is dropped on one side and predates the pill. I also have lots of the random symptoms although generally I'm not too bad with it.
It is the worst of the autoimmune diseases and I know plenty of people who have Lupus and Diabetes with it and call them "minor irritations". The reason it is the worst is that it works by attacking cells which is completely unique, most things attack a specific area - so eczema attacks the skin, arthritis the joints etc - the problem with attacking cells is that everything in your body becomes a potential target and even things you put in your body (food, drink, immunisations, viruses, infections) so you can end up with allergies suddenly developing or any autoimmune disease, most people with the condition have at least two. Because the antibodies are carried by blood your blood cells are constantly under attack so you have "sticky" blood, basically blood that clots too easily.
It also means that the baby is at risk in pregnancy and the antibodies are raised anyway so you're at higher risk just being pregnant. I had a TIA in the toilet after my 20 weeker was born, they made me keep the door to my en suite open because they were worried about me and had to pull me off the loo when I started headbutting the sani-bin!
It is possible to carry a baby with it, it's about 18% (about 1 in 5) chance so some people do have to have a healthy babies and it would seem from the group I use that people who manage it do go on to have a healthy baby again, although being treated is still a good idea because the mother is still at risk herself.
It's often said by doctors and MWs who don't know better (this is a big problem with the condition, HCPs really don't know better but won't admit it and resent the doctor who discovered it so won't refer to his opinion on it) that this is a pregnancy condition but it's really not and it's something that needs to be known about. It needs treatment forever because of it and the risk of family members having it goes up - my sister loves me, she's not been tested positive but she's not allowed the pill because of me so it's needle in the bum! My brother's daughters won't be able to have it and neither will anyone descended from my parents. It's a funny condition because it can appear from no where when there are enough risk factors. The fact that I have enough but we don't know anyone above me who has it means that my parents have likely created it and so anyone below them will have enough risk factors.
I believe and I know Prof Hughes and his team believe it too, that all pregnant women should be tested and all women who lose a baby should be too. Whilst it's hard to get tested for anything with less than three losses, if you've had late loss it's not usually considered to be "one of those things" so they're more likely to test you. You can still ask them to get you tested though.
I know that's a lot of information, I'm sorry if it's rambly but it's such a complicated disease that it's hard to condense it.