I havent had a sample taken from my uterus but I have had some immunolgy testing done and my FS has reccomended clexaine starting day after pick up. This is to be used to create a healthy area inside the uterus so my little bubby can implant and enable the placenta to form without being killed off by my immune system. I dont have a clotting problem but my immune system is working overtime. Good luck with your operation!!! hope you get some answers soon.