During menstrual bleeding, the cervix is normally low and hard and slightly open to allow the blood to flow out. It feels like the tip of your nose.

After your period stops, the cervix remains low and hard and the opening to the uterus (uterine os) remains closed.

As you approach ovulation, the cervix rises up to the top of the vagina and becomes softer and moister.

At the height of ovulation, the cervix feels more like your lips than your nose and the uterine os is open to allow sperm to enter in. Sometimes the cervix seems to disappear – which just means it has become so soft that it blends in with the vagina walls and rises so high that the finger cannot touch it. This is known as SHOW - soft, high, open and wet. This is your most fertile time and is the optimal time to have sex to achieve pregnancy.

Once ovulation occurs, the cervix drops lower and becomes more firm - once again feeling like the tip of your nose. The opening to the uterus will become tightly closed. This can happen immediately after ovulation or may take several hours to several days.

When pregnancy occurs, the cervix will rise up and become soft, yet the os will remain tightly closed. This occurs at different times for different women – as early as 12 days after ovulation or well after the pregnancy has been confirmed by a home pregnancy test or doctor.

http://www.fertilityauthority.com/your-fertility/cervical-position-what-it-tells-you-about-your-fertility

Cervix