The Signs of Fertility

CCL’s Sympto-Thermal Method of NFP is based on three key signs of fertility:

• Cervical Mucus
• Temperature
• Cervix

These are easily noticed by any woman who has learned to watch for them. As these signs are observed, they are recorded on a chart.

The chart provides a daily record that can be used to identify the days of fertility and infertility. And once the fertile and infertile days have been identified, the couples apply “rules” that they learn in class and that are explained in CCL’s Student Guide to identify the boundaries between the phases of the cycle.

Cervical mucus

Cervical mucus appears in response to estrogen. It is a natural, healthy and clean fluid of the body just like tears or saliva. It's necessary for the proper functioning of a woman’s reproductive system.

Mucus is also an aid to fertility because it provides a swimming medium for sperm, provides nutrients for sperm, and enables sperm to survive for days in a woman’s cervix area where the sperm temporarily wait for ovulation.

When there is no mucus, sperm life is very short (just a few hours), because the normal vaginal environment is very acidic and hostile to sperm.

Women can easily learn to become aware of their cervical mucus through what they feel and sense, and what they see. Once observed, mucus is recorded on the fertility chart each day.

Basal Body Temperature

A woman’s body temperature rises after ovulation, so recording the basal body temperature throughout the menstrual cycle provides important information.

A woman takes her temperature each day and records it on her chart (and we encourage husbands to help here!). It’s very simple, and with a digital thermometer, you can take your temperature in a minute or less.

Look at the chart. You may have no experience NFP right now, yet you can probably see the two temperature regions, showing that the temperature has gone up and that ovulation has occurred. This part of NFP really is that easy!

Cervix

The third sign of fertility is changes in the cervix. The cervix has an indentation or dimple where the cervical opening, is located, and women sometimes compare it to the narrow end of a pear with the stem removed.

Like the cervical mucus, the cervix changes in response to both estrogen and progesterone. It is closed and hard until the beginning of the fertile time. As ovulation approaches, however, the cervix opens slightly and becomes softer in response to estrogen, feeling somewhat like your lip. These are gradual changes that usually occur over a period of a week or more. After ovulation, in response to progesterone, the cervix closes and hardens again, and feels similar to the tip of the nose.

Although covered in detail in class, CCL teaches the cervix as an optional sign, and it is not necessary to observe to practice NFP. However, many couples have found it useful and helpful in times of marginal fertility, or during the times of changing fertility after childbirth or during the premenopause.