Basically it's kind of like cholesterol, but stickier. And it attracts more of itself once it's attached somewhere. So, along with all of my pregnancy/fertility issues that we have to watch, now I'm at elevated risk for multiple types of heart disease. Oh, and it may be linked with pregnancy loss, but that's not completely confirmed. Oh joy.
When I told my mom (who has a knack of saying the thing you're thinking and making you laugh about it, even if it's scary) she says "well, you didn't have enough going on, now did you?" I told her that the laundry list of things for me to be worried about felt unbalanced, and I needed to top it off and even it out.