Keen - I was on clexane until I became allergic (a very rare side effect) and most of the literature indicated it had been found safe in pregnancy. It has a short half life (short duration of effect in the body) but there has not been enough numbers to rule it as safe to use in pregnancy. To my knowledge there are no adverse outcomes for the baby and it is usually ceased on the day of delivery (if natural) with no additional bleeding issues for the mother. Deb (Flowerchild) also had a reaction and has been on fragmin but she will also be able to give you details.