Usually, the three primary fertility signs which ovulating women show are changes in:
- Basal body temperature or waking temperature
- Cervical fluid or mucus
- Position of cervix
Basal body temperature (BBT) or waking temperature
The basal body temperature (BBT) is the temperature of the body on waking. It is called basal because it is measured at a time when the body is deeply rested and the body’s metabolism is at its baseline.
A woman’s BBT rises after she has ovulated and begins to produce progesterone. A woman’s preovulatory BBT typically range from about 97.0 to 97.5 degrees Fahrenheit, with postovulatory temperatures rising to about 97.6-98.6. After ovulation, they will stay elevated until her next period. If she were to become pregnant, they would remain high throughout her pregnancy.
Temperatures typically rise within a day or so after ovulation and are the result of the heat inducing hormone, progesterone. Usually, the rise in temperature signifies that ovulation has already occurred. It does not reveal impending ovulation as do the other two fertility signs, the cervical fluid and cervical position.
When interpreting temperatures, the key thing to do is to look for a pattern of lows and highs. See the whole, rather than day-to day changes.
Certain factors can increase your BBT, such as:
- Having a fever
- Drinking alcohol the night before
- Getting less than three consecutive hours sleep before taking it
- Taking is at a substantially different tile than usual
- Using an electric blanket or hot water bottle that you normally don’t use
Cervical fluid or mucus
Cervical fluid or mucus is to women what seminal fluid is to the man. Men produce seminal fluid continually because they are always fertile. Women, on the other hand are only fertile the few days around ovulation, and therefore only produce the substance necessary for sperm nourishment and mobility during that time.
As you approach ovulation, your cervical fluid gets progressively more lubricative. It may change from being sticky to being creamy or lotion like, and then to resembling raw egg white. At this time, it’s slippery and can stretch. You may also notice that the fluid is wet and that you feel a lubricative vaginal sensation.
After oestrogen has peaked the cervical fluid changes abruptly, sometime within hours. There will be a drying of the fluid and the lack of cervical fluid will usually last the duration of the cycle.
Finally, just before menstruation, you may notice a wet and watery sensation, which is due to the drop in progesterone that precedes the disintegration of the lining of the uterus. This is not a fertile fluid.
Factors which can affect cervical fluid are:
- Vaginal infections
- Seminal fluid
- Spermicides and lubricants
- Some medication such as antihistamines, antibiotics, anti-inflammatories, antidepressants
- Coming off the contraceptive pill
Your cervix, the lower part of the uterus which extends into your vagina, goes through cyclical changes throughout the cycle. As the hormones signal the approach of ovulation, the shape, position and texture of the cervix changes.
As with the cervical fluid, the cervix prepares itself for a pregnancy by becoming soft and open around ovulation in order to allow the sperm to pass through the uterus. In addition, the cervix also rises due to the oestrogenic effect on the ligaments that hold the uterus in place.
So the cervix goes from being firm like the tip of your nose to becoming soft and mushy as you approach ovulation. In addition, it is normally fairly low and closed, and rises and opens around ovulation.
Secondary fertility signs
Many women notice other signs and these can be practical information to identify fertile and infertile phases:
- Midcycle spotting
- Pain or achiness near the ovaries
- Increased sexual feelings
- Abdominal bloating
- Increased energy levels
- Heightened sense of vision, smell and taste
- Water retention
- Increased sensitivity in breasts and skin
See Acupuncture and Female Subfertility for more details
Lyttleton J (2004) Treatment of Infertility with Chinese Medicine Churchill Livingstone
Toni Weschler (2003) Taking Charge of your Fertility Vermillon