Implantation Doubling Simulation Calculator

WhenMyBaby's implantation doubling simulator easily shows how when you implant and how quickly the pregnancy hormone doubles corresponds to when a home pregnancy test may accurately work for you if you are pregnant!


initial doubling value; more below

Limits chart size, if needed; more below

When did you ovulate?

Not sure. Calculate (use my last period, cycle and luteal length)
I ovulated On

Simulate DPO Range: This calculator can simulate doubling for 6 to 12 Days Post Ovulation (DPO). However, if you're using a small mobile device and the chart is too wide, you can use this field to limit the DPO Range. As noted on WhenMyBaby's Implantation Calculator (on the chart showing your likely implantation dates) 8 to 10 DPO are the most likely implantation days, an option in the above list, so you may want to zoom into those DPOs.

Note: Use Stickies to set your key cycle dates. Using MyMonthlyCycles? Transport your cycle data to WhenMyBaby's stickies!

About the Simulation Calculator

Home Pregnancy Tests are qualitative, answering Yes/+ (pregnant) or No/- (not pregnant). They do so by comparing the amount of the pregnancy hormone (ie. hCG) in the sample to the amount measured by the test. For example, if a test's sensitivity is 40 mIU/ml, a sample with 40 mIU/ml or more will test postive, and a sample with less than 40 mIU/ml will test negative.

When it comes to doubling, what your actual hCG level is on the day of implantation obviously affects how quickly it increases to a level where a qualitative urine-based home pregnancy test would show positive.

Therefore, to simulate doubling, a starting hCG level, representing what would be present at implantation, is needed. This, however, is one of our cycle conundrums - almost impossible to know for sure.

Luckily, studies give us some good ranges. Many clinical charts indicate that levels during the first week after implantation is between 5mIU/ml to 50mIU/ml, whereas others, including a study specifically designed to determine hCG levels in the first week after implantation, showed levels of less than 1 mIU/ml a day after implantation.

You can choose the initial hCG level which is used for doubling, using the Initial Level drop-down. By simulating with different initial levels, combined with the calculator's 2 and 3 day doubling rates, you can see how it influences when your hCG would likely rise to the level detectable by home pregnancy tests.

With so many variables in the early stages of pregnancy - when implantation will occur, what your starting pregnancy hormone level is, and how quickly it will double - this calculator is an excellent way to view the possibilities, as you wait to see if this is your BFP cycle. Baby Dust!

Disclaimer: This calculator estimates possible implantation dates based on either predicted ovulation date or on the actual ovulation date you specified. These are predictions only, and we make no guarantee that if you are pregnant, that implantation will occur or has occurred on any of the dates calculated, since these calculations are based on general time-frames of when implantation typically occurs after fertilization: implantation may occur earlier or later for you. Doubling values and rates can also not be guaranteed and are intended for general information purposes only.