The core principle of TCM for fertility care is to restore the balance of Qi. I often ask patients to track their BBT using a fertility app. This allows me to identify specific imbalances at different stages of their menstrual cycle. Here are some key indicators of each phase of a 28-day menstrual cycle based on the BBT charts.
Follicular Phase (Day 1 to 13): the Yin Phase
The first phase begins on the first day of your period and is when your follicles develop. In this phase, your BBT should hover at its base level of between 97.1 (36.2) & 97.7 (36.5) degrees. The follicular phase is governed by estrogen, which Chinese medicine views as a Yin hormone. We recommend eating yin and blood-nourishing foods, getting enough rest, and taking your herbs will help to set up a healthier and warmer second half of your cycle. If your follicular phase temperature is too low, this may be a sign of Kidney Yang deficiency. A high temperature may indicate internal heat.
Ovulation (Day 14): when Yin turns into Yang
At ovulation, you should expect an increase in temperature of approximately 0.5 degrees Fahrenheit. Without sufficient Yang energy, the egg might not be able to come out of its follicle. This can lead to anovulatory cycles or delayed ovulation. When there is not enough Yin, the fertile stretchy cervical mucus might not appear.
Luteal Phase (Day 15 to 28): the Yang phase
The second half of the cycle is when the recently ovulated egg travels down the fallopian tube, and the fertilization process may occur. Ideally, the temperature is high and steady. Progesterone is the dominant hormone in preparation for potential implantation. The standard temperature for the luteal phase is between 97.7° and 98.3°F throughout. If your temperature stays up beyond 28 days, then it is a sign that you are probably pregnant!
Low body temperature or short luteal phase are signs of Kidney and Spleen Yang deficiency. This is what TCM refers to as a Cold Uterus. Often there are other constitutional symptoms such as sensitivity to cold, sore back and knees, water retention, fibroid, endometriosis, fallopian tube blockage, menstrual cramps, clots, and dark-colored menstrual flow. Cold Uterus can be caused by two main factors. Number one, improper eating habits, i.e. eating raw, ice cold drinks, being vegan or vegetarian, and not eating meat (TCM considers foods to have warm, cold, neutral energy. For example, beef, lamb, ginger, and turmeric are warm, and fish, crab, cucumber, and leafy green are cold. Consumption of too many cold energy foods leads to the body becoming cold) Number two, improper lifestyle, i.e., staying indoors all day and not getting sun exposure, wearing a small shirt and exposing belly button, wearing V neck and slippers, sitting under the vent, cold invade the body, leading to yang deficiency….
Warming the womb
For an embryo to embed on the lining of the uterus, and continue to thrive, a woman needs to have a warm womb to help blood flow. Chinese herbs and acupuncture are fantastic at regulating blood flow to the reproductive organs and improving the thickness of the uterine lining. In addition, lifestyle and eating habit modifications are part of the care plans. I tend to give individual recommendations based on the patient’s diagnosis.
How to chart BBT?
Use a digital oral thermometer that reads in Fahrenheit up to the 10th degree (example 98.6*F). Download an app such as Fertility Friend (it’s free) that produces a chart from your inputted data. Keep the thermometer on the bedside table. Measures your oral temperature in the morning when you wake up, avoid eating, drinking, or going to the bathroom. All the movements affect the reading. Your BBT can be influenced by fever, stress, alcohol, or travel.