Do you know the many variations that can be on your fertility cycle chart? The purpose of charting the basal body temperatures is to find out when ovulation occurs. To some women, the chart will be “text-book” meaning the lows will be in the 97.0 F range and the highs in the 98.0 range, with a .4 rise the day after ovulation and a 14-day luteal phase (the time from ovulation to menstruation or the start of the next cycle.) This is not always the case, though, and for the majority of women who experience some variations on their temperature charts, there are possible explanations.
Seeing high temperatures on the entire chart, and especially in the first half of the cycle is possibly an indication of hyper-thyroid. If you see this consistently, you should have your physician run a thyroid test to rule out possible thyroid dysfunction. If your thyroid is hyperactive, there are medications that you can take to help balance the thyroid. These medications should also help your basal temperatures to become normal.
2. Low Temperatures
In the opposite direction, temperatures that are too low in both halves of the cycle is a possible indication of low thyroid or hypo-thyroid. Hypo and hyper-thyroid can cause infertility.
Hormonal imbalances other than a dysfunctional thyroid may be to blame for the basal body temperatures being either “too high” or “too low”. Low estrogen would cause the pre-ovulatory temperatures to be higher than normal, on the other hand, too much estrogen would cause them to be lower than normal. Likewise, with all the reproductive hormones, imbalances in any of them will be reflected on the fertility chart.
3. Slow Upward Shift
When a woman has a chart that is fairly normal, then it slowly shifts upward after ovulation, it can be difficult to determine the exact date of ovulation. Normally when ovulation occurs, the temperature shift will be at least .4 of a degree. If the shift takes place in one-tenth increments, it is harder to pinpoint the exact date of ovulation. In this case, careful attention needs to be placed on other signs of ovulation, such as cervical fluid and/or cervical position. Charting these two extra fertility signs can be of great importance when the temperature shift gradually increases.
4. No Shift, Erratic Temperatures
When there are no upward shifts after ovulation, or the temperatures are all over the place from day one until the end of the cycle this is known as anovulation. Anovulation means the absence of ovulation. This can happen even with menstrual bleeding each month. Women who take birth control pills experience anovulation, yet they “bleed” each month during the menstrual period time. The chart will be one of three ways – all low temperatures, or all high temperatures or all over the place.
It pays to research about basal temperatures before charting the fertility signs. Take your chart with you to your healthcare provider for further clarification.