I had a m/c between kids #2 and #3 and thought that low
prog. might be the culprit. Doc dismissed my concerns because I had had two healthy pregnancies before the m/c. I found a doc who would listen, and who tested my levels with baby #3. My levels dropped, so I was put on a prog. supplement. I had a healthy baby girl nine months later. I am now preg. with #4, in a new state with a new doc, and started spotting a couple of days ago. I went in to see new doc, who had tested my prog.