TTC after multiple MC's

I am new to the forum but have had a total of 5 MC's. I had 4 and then a healthy a baby girl but then another MC this weekend, it was an unplanned pregnancy but still just as hard to lose. My HCG levels are already down to a 0 so I have the clearance from my Dr to go ahead and try if I'm ready, but I just don't know how many more MC I can handle. I have had so many tests done its draining, but it was suggested to me to try progesterone as soon as I find out I'm pregnant, has anyone tried this and had any luck? Also does anyone know if there is anyway (other then ovulation kits) to determine when you ovulate from the time you MC? I'm sure there is no science to it but just thought I would ask. Thanks