Taking Charge of Your Fertility

by Toni Weschler

  If you are using FAM for birth control and have established that you are indeed one of the few women whose temperatures simply do not reflect ovulation, you can still use a natural method of birth control by charting cervical fluid only. While not as effective as the Sympto-Thermal Method taught in this book, you can increase its effectiveness by also observing your cervical position, thus providing another sign to cross-check in cases of ambiguity. Appendix F discusses the rules when charting only one sign.

  No thermal shift. There is clearly no pattern of lows followed by highs after ovulation.

  OUTLYING TEMPERATURES

  If you have temperatures that are clearly out of line (for example, from a fever, drinking alcohol the night before, or having slept in and taken your temperature late), simply apply the Rule of Thumb, covering any outlying temperatures with your thumb. Draw a dotted line between the correct temperatures on either side of the aberrant temperature. In calculating the coverline, you count the 6 low temperatures before the rise, not including the outlying temperature, as discussed here.

  If you have an outlying low temperature after your temperature shift, you may apply the same principle of the dotted line. But if you are using FAM for birth control, you should never ignore a low temp if it is within the 3-day count after the thermal shift. To be safe, you must count 3 regular temperatures above the coverline before you consider yourself infertile. Of course, observing your cervical fluid and cervical position will help clarify any ambiguity.

  See Lucy’s and Lauren’s charts below for two examples of how the Rule of Thumb is used, both before and after the thermal shift.

  Lucy’s chart. Outlying temperature within the 6 days before the thermal shift. Note that Lucy counts back 6 low temperatures before the thermal shift, but because she applies the Rule of Thumb, does not include the outlying temperature when drawing the coverline.

  Lauren’s chart. Outlying temperature within the first 3-day count after the thermal shift. Note that as a method of birth control, Lauren considers herself safe only on Day 4 after the thermal shift, since one of her temperatures dropped below the coverline during the 3-day count. If she wanted to be extra conservative, she could wait until the third night in a row of high temps above the coverline. But in this case, both her Peak Day and cervical position were so obvious that she was able to safely consider Day 23 the first safe evening.

  ERRATIC TEMPERATURES

  Some women may find that their temperatures do not seem to follow the classic pattern of lows and highs. For these women, consider trying any of the following:

  1.If using a digital thermometer, verify that the battery is not low.

  2.Add another minute after the beep before removing it.

  3.Consider trying a glass basal body thermometer, since digitals may be less accurate for some women. If you do so, be sure to take your temperature for a full 5 minutes.

  4.Regardless of which type of thermometer you use, consider taking your waking temperature vaginally rather than orally. (Of course, be consistent in how you take it throughout your cycle.)

  5.Remember that certain factors can definitely increase waking temperatures, such as fever, drinking alcohol the night before, or not getting 3 consecutive hours of sleep.

  6.Try to take your temperature about the same time every day. For every hour that you sleep later than normal, your temperature may tend to creep up. Note the time you take it in the appropriate column, and use the Rule of Thumb discussed here to discount aberrant temperatures that may result from sleeping in. (This will prevent you from attributing a high temperature to a thermal shift before it has actually occurred.)

  Erratic temperatures

  WEAK THERMAL SHIFT WHOSE 3RD TEMP DOES NOT REACH 3/10THS ABOVE COVERLINE

  Not all temperature shifts are obvious, which is why it is so helpful to be able to chart your other two primary fertility signs, cervical fluid and cervical position. Regardless, studying the charts in this appendix will help sharpen your interpreting skills.

  It’s imperative that you are able to accurately identify your temperature shift to be able to apply the Thermal Shift Rule. This rule says that you are safe the evening of the 3rd consecutive day your temperature is above the coverline, as long as the 3rd temp is at least 3/10ths above. However, if it doesn’t reach a full 3/10ths, you could still rely on FAM for contraceptive purposes by waiting until the evening of the 4th temp above the coverline, as seen in the chart below.

  Carlie’s chart. A weak thermal shift. Carlie normally has a fairly obvious thermal shift, but this cycle her temperature on Day 18 was not at least 3/10ths about the coverline. However, that day was 3 days past her Peak Day, and her cervix was back to low, closed and firm. Still, to be even more conservative, she chose to wait until she had 4 temperatures above the coverline, starting on Day 19.

  Note that on Day 10, when she technically started her fertile phase because she began to develop sticky-quality cervical fluid, she had intercourse using both a condom and a diaphragm. After that day, though, she and her partner abstained until Day 19.

  TEMPERATURES THAT RISE 1/10TH DEGREE AT A TIME (SLOW-RISE PATTERN)

  Some women will notice that instead of their temperature shifting by at least 2/10ths of a degree higher than the cluster of the previous 6 lows, their temperatures may occasionally rise by merely 1/10th of a degree at a time. While this type of shift may seem confusing to interpret, it’s actually fairly easy.

  Notice the first time your temperature rises at least 1/10th degree above the highest of the last 6 temperatures. Once it increases another 1/10th degree, go back and highlight the 6 days before the first rise. Draw the coverline through it. After your temperature remains above the coverline for at least 3 days, and the 3rd temp is at least 3/10th above the coverline, you can consider yourself safe that 3rd night.

  For pregnancy avoiders, to be conservative with this fairly rare temperature pattern, if your temperature does not rise to at least 3/10th above the coverline by the third day, you could choose to be a bit more cautious, and thus not consider yourself to have entered your infertile phase until either:

  •the evening of the 4th temperature above the coverline

  (rather than the 3rd above)

  •the evening of Peak plus 4

  (rather than Peak plus 3)

  For pregnancy achievers, you should consider the postovulatory phase to be all the temperatures above the coverline, but realize that your ovulation may have occurred a day or so earlier. Remember that ovulation most likely occurs the day of, or the day after, the Peak Day.

  See the chart below for how a slow-rise pattern would look on your chart.

  Keara’s chart. Slow-rise pattern. Note the subtle rise of only 1/10th degree starting on Day 17, the first temp higher than the previous 6 before it. To be conservative for birth control, Keara wouldn’t consider herself safe until the 4th high temperature, which is the 3rd true temp above the coverline—Day 20 in this cycle. Note that she is also being conservative by waiting until Peak plus 4 rather than Peak plus 3. In this case, the two conservative rules coincide. If they hadn’t, it would have been a perfect time to corroborate those signs by also observing her cervix, which should be low, closed, and firm, before considering herself safe.

  TEMPERATURES THAT RISE IN SPURTS (STAIR-STEP PATTERN)

  One of the more common types of temperature patterns are those where the thermal shift occurs in an initial lower spurt of several days, followed by higher temps after. In other words, you will probably notice a cluster of 6 low temperatures followed by a shift of at least 2/10ths higher for perhaps 3 or 4 days, followed by still higher temps. The coverline is always drawn after the first shift of at least 2/10ths higher than the cluster of 6 preceding low temperatures.

  For pregnancy avoiders, if your temperature does not rise to at least 3/10th above the coverline by the 3rd day, you should not consider yourself safe until:

  •the evening of the 4th temperature above the coverline

&nb
sp; (rather than the 3rd above)

  •the evening of Peak plus 4

  (rather than Peak plus 3)

  For pregnancy achievers, when calculating your luteal phase, you should consider the postovulatory phase to be all the temperatures above the coverline.

  Danielle’s chart. Stair-step pattern. Note the initial spurt of 3 high temps on Days 17, 18, & 19. To be conservative for birth control, Danielle could have waited until the 4th night above the coverline, since her temps rose in spurts that hovered near it. But because her Peak Day was on Day 15 (as seen in the Peak Day Count row near the top of the chart), Day 19 was already conservative for the Peak Day Rule, since it was Peak plus 4 at that point. Still not wanting to take a chance, she chose to use a condom and a diaphragm on that day, and then considered herself completely safe on Day 20.

  TEMPERATURE THAT DROPS ON DAY 2 OF THE THERMAL SHIFT (FALL-BACK PATTERN)

  Some women notice that they tend to have a pattern of a temperature drop on Day 2 of their temperature shift, followed by a sustained rise in temperatures until their period. If it is only a one-day drop, there is no need to re-draw the coverline.

  For pregnancy avoiders, to be conservative, you would want to start the count over again after the second sustained rise to be absolutely sure that the egg(s) are dead and gone. If you don’t want to wait the extra 2 days, you could rely on the Peak Day Rule to signal the start of the infertile phase. Admittedly, this could compromise contraceptive efficacy, but if you verify that you are once again dry, your temps have returned to their highs above the coverline, and your cervix has returned to its infertile state of low, closed, and firm, the increased risk of conception would be small.

  For pregnancy achievers, you should assume that you ovulated about the day of, or day after, your Peak Day. As you know, this is the last day of wet-quality cervical fluid or lubricative vaginal sensation.

  Katrina’s chart. Fall-back pattern. In this cycle, Katrina’s temp dropped below the coverline on Day 2 of her thermal shift. To be conservative, she needed to start the count over when it rose above the coverline again. (In fact, even if her temp had not dropped below the coverline, it still would have been safest to do Peak + 4 because her third post-thermal shift temp on Day 19 was not at least 3/10th above that coverline.)

  In this case, because her Peak Day was the same day as her Thermal Shift on Day 17, she needed to do a Peak plus 4 count instead of Peak plus 3. These conservative adaptations meant that she wasn’t safe until Day 21 of this cycle.

  FEVER

  You will inevitably have a fever now and then while charting. Practically speaking, it’s best handled by using the Rule of Thumb, as discussed on page. Assuming the temperature is off the chart (as it were), you can simply record the higher temperature above the 99, noting the symptoms of your illness in the Notes row. Be sure to draw a dotted line between the normal temperatures on both sides of your fever. Also, remember that if you’re using a glass BBT thermometer, you’ll need to switch to a digital or fever thermometer for the days that you are sick.

  Depending on the intensity of the fever and when it occurs in the cycle, there are three possible impacts that it could have. It could:

  1.Have no effect

  2.Delay ovulation, causing a longer than usual cycle

  3.Suppress ovulation, causing an anovulatory cycle

  If the fever occurs after you’ve already ovulated, it will almost certainly have no effect. If it occurs before you’ve ovulated, any of the three are possible.

  For pregnancy avoiders, you can continue to use FAM as birth control using all the rules described in Chapter 11. However, if your illness is preovulatory, you obviously have to eliminate the temperatures discounted by the fever, and thus you cannot begin the 3-day count for the Thermal Shift Rule until you are no longer sick. Never assume you’ve entered your postovulatory infertile phase until you can clearly verify a temperature shift of 3 consecutive high temperatures without the interference of any fever. And before assuming that you’re safe, verify that your other fertility signs also reflect that you’ve entered your infertile phase, as seen in Tracy’s chart below.

  The one time in the cycle when this can be a bit tricky is if you get sick in the few days immediately leading up to ovulation, as seen in Ali’s chart below. Still, you should be able to verify that ovulation has occurred, since once you’re no longer sick, your temperatures will drop down to the higher range of temperatures that you would normally have after ovulating. If the fever delayed (or suppressed) ovulation, your temperatures would drop all the way back down to their lower preovulatory range.

  As always, you should remember that the most effective way to use FAM as a contraceptive method is to be sure that at least two of the primary fertility signs coincide. By doing this, it’s unlikely that you will misinterpret the fever for a thermal shift.

  Tracy’s chart. Fever before ovulation. On Day 8 of her cycle, Tracy awakens to a bad flu, which pushes her temperatures off the chart for 3 days. She uses the Rule of Thumb for Days 8 to 10, in this case omitting those temps that are 99 or above. After recovering, she is able to verify that she still has not ovulated, since her temperature returns to its lower preovulatory range on Day 11. As she continues to chart, her signs reflect a delayed ovulation, which in this case probably occurs about Day 20.

  Ali’s chart. Fever during ovulation. Ali awakens to a cold and low-grade fever, starting on Day 12. She uses the Rule of Thumb to discount Days 12 to 14. Completely recovered by Day 15, she notes that her temps have fallen only to her relatively high postovulatory range. Thus she is able to start her temp count on Day 15, and by Day 17 she confirms through her two other primary fertility signs—cervical fluid and cervical position—that she has already ovulated. (Had her illness been intense enough to delay her ovulation, her temperature would have returned to its lower preovulatory range.)

  APPENDIX I

  Using FAM While Breastfeeding

  Be aware that this appendix will be confusing if you haven’t internalized the basic principles and rules discussed in Chapters 6, 7, and 11. In addition, you will need to read the next appendix to apply the contraceptive rules for anovulatory cycles.

  If possible, I would encourage you to consult with a FAM or NFP counselor before relying on natural birth control while breastfeeding, since your fertility signs during this time can be ambiguous. You can find FAM instructors through the links here.

  For those optimists who think you’ll actually have time for lovemaking after having a baby, this appendix is for you. While breastfeeding is a wonderful experience for most women, it can be challenging to identify when fertility will return, even for those who have charted before. So let’s set the record straight right from the very beginning:

  Women can get pregnant while breastfeeding, especially if they don’t chart their cervical fluid!

  So why all the confusion about whether or not women are fertile while nursing? In fact, everybody knows a neighbor, friend, or relative who swears she did or didn’t get pregnant while breastfeeding. These women then become the standard by which people judge the effectiveness of breastfeeding for birth control.

  Part of the problem is that most breastfeeding women are under the faulty impression that as long as their periods haven’t returned, they can have sex with impunity. No period, no problem, right?

  Wrong. Those of you who have already read this book can recite in your sleep what the flawed logic is with that thinking. Remember: ovulation occurs before menstruation, so just because you haven’t gotten a period yet, you can still release an egg and get pregnant without ever having had to use a single tampon since before you gave birth!

  In any case, the reason why some nursing women do get pregnant and others don’t comes down to how they breastfeed, or more specifically, how intensively and how frequently. It’s actually simple biology, for every time a baby suckles at the breast, the mother releases prolactin and oxytocin, which in turn inhibits various ovulatory hormones, i
ncluding luteinizing hormone (the LH of the celebrated LH surge).

  HOW BREASTFEEDING AFFECTS THE RETURN TO FERTILITY

  Different types of breastfeeding will produce different outcomes in terms of a woman’s return to ovulatory cycles. If you are planning to nurse, you might want to consider the advantages, disadvantages, conveniences, and consequences of three different ways of doing it. More specifically, the three factors that suppress ovulation while breastfeeding are the following:

  •duration in months

  •frequency of feeds per 24 hours

  •intensity of nursing—or more specifically, when you start to introduce bottles, solids, etc.

  The Duration of Breastfeeding

  Of all the key issues, this is about as straightforward as they come. This simply refers to the length of time you nurse. Of course, as you would expect, the more months you breastfeed, the greater chance that you will suppress ovulation.

  The Frequency of Suckling

  The more frequently the baby suckles, the less likely ovulation will return. While there are many factors that influence the return of periods during nursing, it is the frequency, rather than duration, which has the greatest impact on a woman’s fertility. Thus, for example, if your baby merely sips from your breasts for 2 minutes every 20 minutes, that is more likely to release ovulation-suppressing prolactin than if he nurses for 6 minutes once an hour.