Fertility Education Trust

understanding your fertility, page 10 of 14

Summarizing the Events of the Cycle

A cycle starts with the first day of menstruation. How the cycle ends will depends on whether the couple had intercourse in the egg ripen fertile phase as shown below.

At some point after menstruation: 1. An egg ripens (approximately 5 - 6 days); 2. The body prepares for pregnancy (10 - 16 days); 3. Intercourse in the fertile phase can result in pregnancy, whilst no intercourse in the fertile phase results in menstruation.

The Pregnancy Cycle

At some point after menstruation (variable phase), an egg will be chosen and begin to ripen. As it ripens, the fertile “motorway” mucus is produced to attract and feed sperm. (top diagram)

If intercourse takes place in the fertile phase the egg can be fertilised. The womb lining will thicken, the cervix will be closed and sealed with mesh mucus. (middle diagram)

The baby can implant in the enriched womb lining to continue its growth and development to birth.
(bottom left diagram)

The Cycle Without Pregnancy Occurring

If no intercourse takes place in the fertile mucus phase, the egg cannot be fertilised. (top diagram)

The unfertilised egg dies quickly, the womb lining builds up as usual for 10 - 16 days and the cervix is sealed with a thick “mesh” mucus plug. (middle diagram)

However, because no conception and implantation occurred, after 10 - 16 days the womb lining will be discharged in menstruation. (bottom right diagram)

- and the whole process starts again with a new cycle