Sustained Elevated LH in blood: what are the causes?

Women naturally produce LH throughtout the month, but OPK's are trying to find the day when that LH surges past a women's normal baseline LH. It's possible that your baseline LH is a little to high for these over-the-counter kits, but if it were me, I'd have a Dr. order a set of hormone tests to be certain that everything is okay. (Also, just as an anecdotal aside, I'd believe the temp charts ahead of the OPK. I used bbt to conceive my son, as I could never get an OPK to accurate predict ovulation, and I tried them for months.)