Pre-eclampsia

So because my mum had pre-eclampsia 3 out of 4 pregnancies I have been prescribed folic acid and aspirin to take from 12 weeks (today) until I have the baby. Has anyone had to do this and still developed pre-eclampsia? It is something I worry about because with my mum she nearly died with my older brother and me and my younger brother were premature (I was born 8 weeks early bro was 10 weeks early).