Your fertility signs each tell you something different about what is happening in your body. Each one relates to a different hormone and your hormones are driving your fertility cycle.
Signs that show you that estrogen is increasing are important for helping you time intercourse during your fertile time, as you are usually most fertile in the days before ovulation when the ovarian follicle is maturing. The ovarian follicle produces estrogen as it is maturing. Signs that show you that estrogen is increasing are:
A positive OPK tells you that LH (luteinizing hormone) is surging and that you will probably ovulate within 12 to 48 hours. The OPK is also good for helping you time intercourse. Neither the OPK nor the signs related to estrogen will help you pinpoint ovulation and they can not tell you definitively that you have ovulated. They are important for helping you time intercourse and for correlating with your temperature to give you the best overall analysis.
Your basal body temperature, or BBT, relates to the hormone progesterone. Progesterone, released by the corpus luteum after ovulation, causes your body temperature to rise, and is only present after ovulation. When you see a temperature shift, you know that you ovulated the day before the shift. Because it allows you to confirm ovulation, BBT usually gives the most peace of mind and allows the most insight into a completed menstrual cycle. All your other signs can occur with or without actually ovulating, but your chart will only show a biphasic temperature pattern when you ovulate.
Fertility Friend takes all signs into account, both to help you determine your fertile time and to help you pinpoint ovulation. Fertility Friend will use all data to help you get as complete a picture of your fertility as possible.