How does the basal body temperature develop after implantation? We show you how the temperature can drop and rise after implantation.
Many women who want to have children rightly ask themselves how the basal body temperature develops after implantation and whether the nidation of the fertilized egg can be recognized by the basal body temperature curve. Two phenomena are particularly interesting in this context, namely that there tends to be a drop or rise in temperature after implantation. In this article, we would like to take a closer look at the basal body temperature during implantation and uncover its secrets.
How does the basal body temperature develop after implantation?
We show you how the temperature can drop and rise after implantation.
#1 Basal curve in the egg maturation phase
During the egg maturation phase, the egg matures from the follicles in the ovary. This produces the hormone oestrogen, which rises sharply until before ovulation. The production of oestrogen suppresses the production of progesterone and therefore the basal body temperature is lower compared to the phase after ovulation. This is also referred to as the low basal body temperature.
#2 Temperature rise after ovulation
Shortly after the egg is released during ovulation, the follicles in the ovary, which produce oestrogen, are transformed into a new gland, the corpus luteum. This corpus luteum now produces a new hormone, progesterone. The higher the progesterone level in the blood, the higher the basal body temperature. For this reason, there is a rise in temperature shortly after ovulation as soon as the progesterone is produced.
Pinpoint ovulation to within 4 days
Recognizing ovulation – basal body temperature
Recognizing ovulation based on basal body temperature with the NFP method © Gnoth, Christian & Frank-Herrmann, Petra & Bremme, M & Freundl, Guenter & Godehardt, Erhard. (1996). How do self-observed cycle symptoms correlate with ovulation? Zentralblatt für Gynäkologie. 118. 650-4.
If, in addition to your basal body temperature, you also monitor your cervical mucus during your cycle, the NFP method can be used to pinpoint ovulation to within 4 days using the basal body temperature curve. This is particularly interesting during the fertility phase, as it allows you to clearly determine if and when ovulation has taken place in your cycle.
Learn the NFP method and interpret the basal body temperature curve
If you would also like to learn how to determine ovulation with NFP, we recommend our eBook “WHEN AM I FERTILE?” There you will find a step-by-step guide to the NFP method including practice cycles + solutions, tips for everyday life and recommended NFP thermometers, testimonials and much more.
# 3 Temperature high in the corpus luteum phase
In the corpus luteum phase after ovulation, the lining of the uterus is prepared for the
possible implantation of the egg. As a result, the progesterone level is elevated and the basal body temperature remains elevated after ovulation compared to the egg maturation phase. Oestrogen levels are generally low – which is logical, because without follicles, not as much oestrogen can be produced. Now there are two possibilities. Either you are pregnant and the basal body temperature curve remains elevated for around three months or even longer after ovulation, or you are menstruating and the basal body temperature drops again shortly before or during your period. This means that the basal body temperature curve can be used to detect pregnancy with 99% certainty, even without a pregnancy test.
Basal body temperature after implantation – what does it look like?
Implantation of the egg takes place around 6 to 12 days after ovulation, which you can observe with the NFP method close to the rise in temperature. Around 84% of women experience implantation between 8 and 10 days after ovulation. This means that egg nidation usually occurs during the temperature peak after ovulation. Interestingly, two very spectacular phenomena now occur, which we would like to discuss in detail.
#1 Temperature rise during implantation – Triphasic cycle
Some women experience another rise in basal body temperature during the temperature peak after ovulation. This results in a basal body temperature curve with a rise after ovulation and a staircase-like progression. We refer to a normal basal body temperature curve with a low and a high as a biphasic cycle, i.e. a two-phase curve. Strictly speaking, we are dealing with a three-phase curve due to the second temperature rise in the high phase, which is why this phenomenon is referred to as a triphasic cycle. If this second temperature rise in the cycle takes place in the period from day 6 to 12 of the cycle, it could be a sign of implantation.
Do triphasic cycles indicate implantation?
In terms of timing, it would fit very well, as most triphasic cycles occur between the 6th and 12th day of the cycle after ovulation. But can this renewed rise in temperature really indicate implantation? Unfortunately, there are no studies on this, but there is a survey by the cycle app Fertility Friend. There you can see that around 12.8% of pregnancy curves are triphasic temperature curves. In contrast, only 4.4% of non-pregnancy curves are triphasic. So, statistically speaking, there is a more frequent rise in temperature after implantation. However, the triphasic cycle cannot be a clear implantation symptom, otherwise the triphasic course would not occur in non-pregnancy curves. However, this cannot be clearly clarified here because there are too few studies on this. It could also be that the 4.4% were pregnant after all, but had a very early termination.
#2 Temperature drop after implantation – the “implantation dip”
Another phenomenon circulating in many fertility forums is the sudden drop in temperature after implantation. This drop in temperature after nidation is referred to in the English literature as the “implantation dip” and is said to occur spontaneously for only one day around 6 to 12 days after ovulation, i.e. during implantation.
Implantation dip occurs more frequently in pregnancy curves
In Germany, the “implantation dip” is referred to as the implantation low point. There have not yet been any studies on this phenomenon. However, there is an analysis of 117,000 cycles by the cycle app Fertility Friend, which took a closer look at the drop in temperature after implantation. The analysis showed that 23% of cycles with implantation dip are pregnancy curves. However, this spontaneous drop in temperature for one day in the luteal phase was also observed in 11% of cycles WITHOUT pregnancy. This means that the “implantation dip” is not a clear symptom of implantation.
Temperature rise and fall after implantation in my pregnancy cycle
I have to honestly say that my second pregnancy cycle was the most significant and interesting cycle in my entire life. First of all, I could hardly believe that I got my period normally during this pregnancy cycle.
My temperature drop after implantation
I also had a drop in temperature after implantation, which unfortunately I didn’t document very well. However, you can see that the basal body temperature is significantly lower again on the 9th day after ovulation and is almost on the help line. Now we know from studies that in 84% of cases implantation takes place in the period of 8 to 10 days after ovulation and the 9th day after ovulation is statistically the most common day for implantation. So I clearly had an “implantation dip” and got pregnant.
Triphasic pregnancy cycle
But that wasn’t all, because I was also able to observe a second rise in temperature during the luteal phase. Finally, my basal body temperature rose again on the 13th day of my cycle after ovulation, so that I actually had a triphasic cycle.
Is this cycle a gift for my NFP work?
Of course, my two wanted children are the greatest gift in my life and they fill me with joy every day. However, I have to say that I really can’t comprehend my 2nd pregnancy cycle. It is extremely rare to get a period in a pregnancy cycle. The “implantation dip” doesn’t occur that often either. A triphasic cycle is also a rather rare phenomenon, which is not observable in every pregnancy cycle. But how likely is it that a woman can experience all three phenomena in one pregnancy cycle? Perhaps this pregnancy cycle was a kind of gift to me for my years of work to spread the NFP method ;-D In any case, as a long-time NFP user, I am still flashed by my 2nd pregnancy cycle today and I have decided to frame both pregnancy cycles and hang them in my living room.
Basal body temperature is a very interesting bodily sign which, in combination with cervical mucus, can be used to clearly determine ovulation and pregnancy. In the case of basal body temperature at implantation, both the rise in temperature (triphasic cycle) and the drop in temperature after implantation (implantation dip) occur statistically more frequently in pregnancy curves. However, the really interesting basal body temperature curves also occur in non-pregnancy curves and are therefore not clear implantation symptoms. I have compiled the most common signs of implantation for you in my article “The 7 most important implantation symptoms”.
Measuring your basal body temperature is worthwhile for you too!
How often do I hear from women that I only monitor my cervical mucus and that taking my basal body temperature is too time-consuming for me? Many of these women don’t get pregnant and have no idea why it doesn’t work. The problem is that cycle diagnostics are only possible in cycles where basal body temperature and cervical mucus are monitored. You would also miss or not even notice such interesting phenomena as the “implantation dip” and the “triphasic cycle”. In my opinion, there are at least 7 good reasons to measure your basal body temperature so that your dream of having a baby comes true as soon as possible. I would like to end this article with a slightly modified quote from Albert Einstein, who once said:
“Look deeply into the nature of the basal body temperature curve and then you will understand everything better.”
Wilcox AJ, Baird DD, Weinberg CR. Time of implantation of the conceptus and loss of pregnancy. N Engl J Med. 1999 Jun 10;340(23):1796-9. doi: 10.1056/NEJM199906103402304. PMID: 10362823.