I gave birth to Caitlyn on the 15/11/05. She was stillborn at 25 weeks. My OB will start me on aspirin and clexane early into any future pregnancy to assist in placental implantation. Apparently the placenta implants initially and then further implants at around 22 weeks. I have notice since losing Caitlyn that many stillbirths occur at around the 25 week mark and it may be (just me guessing) due to placental insufficiency. I didn't know the placenta implanted further after the first trimester and her 18-20wk U/S was perfect. She was smaller than she should have been for dates when she was born so she may not have been getting enough to grow.
Add to this the fact that I have Factor V Leiden ( a clotting disorder) and I become a high risk for at least the first 2 trimesters.
Clexane has a very short half life (meaning it only lasts in the body for a short time) so my OB will not be ceasing my clexane. It will continue until labour / delivery. The aspirin will stop at around 30 weeks.