Fertility Education & Training

guidelines to charting your fertility cycle, page 21 of 26

4. The Double-Check Concept

Dr. Anna Flynn FRCOG, who set up the NFP Teachers Association, dedicated much of her time as a gynaecologist to teaching Natural Family Planning, to researching and refining the rules to make it as efficient as possible. She soon realised that the more indicators a woman / couple could use to double-check their symptoms, the higher the success rate.

the infertile phase after ovulation

There were already two indicators to define this phase:

When both were used to double-check each other, the couples were very confident and the success rate was high. When the post ovulation phase alone is used, the pregnancy rate is virtually zero.

the infertile phase before ovulation