To describe the natural history of a condition or disease. To describe the natural history of a condition or disease. To determine effectiveness or cost effectiveness of treatments/services and/or health care products. To measure or monitor safety and harm. To measure quality of care.
According to the NMSS, attacks or flare-ups of symptoms only qualify as exacerbations if: 1  they occur at least 30 days from an earlier flare-up. 2  symptoms last for 24 hours or longer.
The first is so that you can see if your LH surge corresponds properly with your thermal shift. You should shift 1-3 days after your positive OPK, though sometimes it takes as long as five days for those with a slow shift. Another reason is to make sure your temperatures stay up for at least 10 days after ovulation.