There is a great interest in identifying very early pregnancy signs on charts. Which signs can tell you that you might be pregnant? Which are meaningless? To try to answer this question quantitatively, we have run some statistics on a large sample of charts.
One of the most controversial and puzzling potential signs has always been a luteal phase dip. There has been a lot of speculation about the significance of a temperature dip in the days after ovulation around the time implantation would be expected. We wanted to get to the bottom of the issue and find out once and for all if seeing a dip in the luteal phase, around the time of expected implantation, increased the probability of pregnancy.
Here is what we did:
We ran a full statistical analysis on 116,691 charts recently processed by Fertility Friend, both pregnancy charts and charts that did not result in pregnancy.
To be considered as a dip, charts had to show a significant single dip that lasted a single day, occurring between 5 and 12 days past ovulation.
We used a minimum dip size of 0.3F. We also ran the test using several pattern recognition algorithms to validate the correlation independently of the method of measurement.
Here is what we found:
11% of charts that showed ovulation but did not result in a pregnancy displayed this pattern.
23% of charts that showed ovulation and did result in a pregnancy showed this pattern.
Of the pregnancy charts that showed this pattern, the most likely days for the dip to occur were between 7 and 8 days past ovulation.
The data suggest that this pattern is indeed more likely to result in a pregnancy.
Remember, though, if you have this pattern, it does not necessarily mean that you are pregnant. It is just increasing your probability.
No matter your chart pattern, you can still be pregnant as long as you have well-timed intercourse within your fertile time. In the end, the only way to really know for sure whether or not you are pregnant is still when you can reliably take a pregnancy test.
See also: Cause of implantation dip.