Implantation Calculator – When Does Implantation Bleeding Occur? info_circle_iconHow To Use This Calculator ?
It is simple. And it depends on the way you are trying to conceive – natural or through fertility treatment. If it is a natural way, enter the first day of your last menstrual period and the average cycle length. It would be even better if you know your ovulation date. If you have undergone a fertility treatment, you should pick your embryo transfer date. Once you give these details, you will get the dates, which are important for you to know about conception.>

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Implantation is the initial phase of pregnancy when a fertilized egg adheres to the uterine wall. It is most likely to happen around nine days post ovulation but can range from six to 12 days. Here is one such calculator that shows the possible implantation dates based on when you have ovulated or when your last menstrual period was. This is when the pregnancy hormone doubles quickly and lets you know when to take a pregnancy test that comes positive.

Note: If you know when you have ovulated, please select the "Ovulation Date" and if you don't know the date of your ovulation, please select the "First Day of LMP".

Average Cycle Length


When Does Implantation Most Likely To Occur

implantation calculator for pregnancy

Implantation is a critical step in the conception process. It is the time when the embryo adheres to the uterine wall. You may see light spotting or bleeding after implantation and that is one good sign for you to note the time of implantation.

Implantation period is very short, and therefore the sperm needs to be ready to meet the egg. If the sperm is too early or late, it cannot form an embryo.

Ovulation, which is the release of eggs, typically happens around 12 to 14 days after the first day of a period (or the start of a new cycle). Implantation occurs 6 to 12 days post ovulation.

Calculating the ovulation dates, menstrual cycle and implantation can be very confusing. This is where an implantation calculator will help you. This calculator also helps you understand that the bleeding you have spotted is not because of a miscarriage or your next period, but due to implantation.

(Read more : What are the first signs of implantation?)

Difference Between Implantation Bleeding and Menstrual Period

Implantation Bleeding vs Menstrual Period

Implantation Bleeding occurs around seven to 14 days past ovulation (DPO) when the fertilized egg is implanted in the lining of uterus wall. While it’s happening, a small part of uterine lining can be released or disturbed, resulting in bleeding. Implantation Bleeding or spotting is usually pink or dark brown in color. Whereas period blood tends to be bright and vibrant red. During implantation, the blood takes time to travel from the uterine wall to the vagina, and thus it changes color from red to dark brown or pinkish as it is no longer fresh. Implantation bleeding is lesser. At times, the bleeding could just be a single spot, on go for few hours or up to 1 - 2 days. But, if bleeding starts lighter and gets heavier later with constant flow and continues for 4 to 7 days then it is certainly your menstrual period.

Implantation bleeding occurs about 10 days past ovulation. So, if you find pinkish or dark brown spotting on the 22-25th day from your LMP that this could be implantation bleeding. While menstruation generally occurs 14 days past ovulation i.e around 26-27th day from LMP. During Implantation bleeding, a woman can experience light and low strength abdominal cramps whereas menstrual cramps are more intense and stronger.

Most Frequently Asked Questions About Implantation

Q. What does implantation cramping feel like?

Cramping is also a sign of implantation. Most women tend to confuse implantation cramping with menstrual cramping. But the major difference is that former is milder and lasts longer. The cramping is usually felt in the lower back because of the regular series of contractions that the walls of the womb undergo.

Q. How long does implantation cramping last?

Implantation cramping can last over one or two days.

Q. How common is implantation cramping?

Implantation cramping is quite common at that stage, but varies from one woman to another. There are also chances of it not occurring at all during the process.

Q. When can you take a pregnancy test?

The level of hCG hormone has to be more than 25 mlU/ml for the pregnancy to be detected. If the level is lower than this, the pregnancy cannot be detected, even after implantation. Therefore, you must wait at least a week or two after missing the period to take the pregnancy test.

If you experience these signs and have a delayed period, it’s likely that you are pregnant. To get the exact results, take a home pregnancy test. It will give you accurate results. If you get negative results, wait for at least three days before you do the test again.

You can even get a blood test done to see if you are pregnant. Blood tests are more accurate than home pregnancy tests. These tests will give you accurate results as early as 6 days after ovulation.

Q. How Accurate Is An Implantation Calculator?

An implantation calculator may provide a fairly accurate estimate of the implantation time for women with regular menstrual cycles. However, if the cycles are irregular, it can be more difficult to predict the time of ovulation and implantation, resulting in lower accuracy.

Q. Can An Implantation Calculator Predict When I Will Ovulate?

No, an implantation counter is not designed to predict ovulation. It tracks implantation depending on your ovulation date or the starting date of your last menstrual period.

Q. Can An Implantation Calculator Predict The Due Date Of My Pregnancy?

No, an implantation calculator will not return results predicting an expected delivery date (EDD). EDD is calculated using the date of the first day of your last menstrual period after pregnancy has been confirmed.

Q. Can I Use An Implantation Calculator If I Have Conceived Through In Vitro Fertilization (IVF)?

Yes, an implantation calculator may be useful if you have conceived through IVF, as you will know the date of your ovulation in that case.

Q. How Can I Confirm If I Have Had Implantation Or If My Symptoms Are Due To Something Else?

You may use a home pregnancy urine test to confirm that implantation has occurred. Such tests are usually most accurate when done a week or two after you've missed your menstrual period.



Remember, the implantation calculator is one of the many ways to determine pregnancy, not the only one. If you have any concerns regarding pregnancy or implantation or if any of these symptoms persist, contact a gynecologist.

Do you have any questions regarding the implantation calculator or any other related topics? Tell us in the comment section below!

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