When I Got Pregnant Calculator


Are you trying to figure out exactly when you got pregnant?

Sometimes, pregnancy occurs when people least expect it, and knowing when it happened is also not easy. According to statistics, over 3 million unplanned pregnancies occur in the US.

Yes, sex leads to pregnancy, but how soon after sexual intercourse can one get pregnant? 

Getting pregnant is not as simple as “boy meets girl and pregnancy happens”. Some variables determine when you get pregnant, so it is pretty tricky to tell exactly when you got pregnant.

After unprotected sex, you can get pregnant in minutes, hours, or days – or not at all. Learning more about your menstrual cycle, fertile window (ovulation days), and sex timing will help you figure out when you got pregnant.

“When I got pregnant calculator” helps you to discover when you got pregnant by monitoring your menstrual cycle and figuring out your fertile window against the time you had unprotected sex.

This calculator is helpful if you are facing an unplanned pregnancy and trying to figure out who got you pregnant

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What Happens Before You Get a Positive Pregnancy Result

After sex comes pregnancy, right? 

As correct as this is, sex doesn’t automatically equate to pregnancy. There is a process that leads to pregnancy. After unprotected sex, fertilization and implantation happen before you may start to notice early pregnancy symptoms. 

Conception doesn’t just happen in between the time it takes for the sperm to fuse with an egg. Some factors may determine how quickly or slowly the sperm can swim and fuse with an egg. 

Do you know that sperm can survive for up to 5 days inside the female reproductive system?

That said, the time that sperm fuses with the egg determines when fertilization happens. For example, if you had sex on Monday and then your body released an egg on Thursday, then fertilization will take place on Thursday even if you had sex on Monday. 

If one of the sperm cells released during intercourse penetrates the egg, they become fertilized and development begins. At this point, you can say that fertilization has occurred.

Even if fertilization occurs after a sperm joins with an egg, it doesn’t always mean that pregnancy will occur. If the fertilized egg doesn’t implant in the uterus, then pregnancy may not occur.

What is Implantation and How Does it Happen?

Implantation is an essential pregnancy process that happens when a fertilized egg attaches to the uterine wall. When the fertilized egg travels through the fallopian tube and eventually attaches itself to the walls of the uterus – pregnancy occurs. 

It takes several days for a fertilized egg to travel down from the fallopian tube to the uterus. When it finally reaches the uterus, it will attach itself to the lining of the uterus called (the endometrium).

The tricky thing about implantation is that not all fertilized eggs get implanted. If the fertilized egg doesn’t implant, then the body will shed both the egg and the lining of the uterus as menstruation.

However, if the fertilized egg successfully implants in the lining of the uterus, a hormone called human chorionic gonadotropin (hCG)starts to be produced in the uterus. This is the hormone that a pregnancy test measures and this will possibly be when you start to notice early signs of pregnancy. 

The process of unprotected sex, fertilization, and implantation is what eventually leads to pregnancy. These processes determine when you got pregnant. 

How Knowing Your Ovulation (fertile window) Helps You Determine When You Get Pregnant

Have you heard people say that not all sex leads to pregnancy?

Well, that is true. You don’t fall pregnant every time you have unprotected sex because you are not fertile all the time. Pregnancy can occur on a few days in your entire menstrual cycle, but why is that?

It is because you can only get pregnant when your ovaries release an egg that sperm will possibly fertilize. Your ovaries do not release eggs every day, they release an egg once in your entire menstrual cycle every month. 

The process of your ovaries releasing an egg is called ovulation. There is a higher possibility for you to get pregnant when you engage in unprotected sex during ovulation.

How Ovulation Helps You Detect When You Got Pregnant

You have a higher chance to get pregnant if you have sex 1-2 days before ovulation. If you have a regular menstrual cycle, you can count back half of your menstrual cycle length. 

For example, if you have a 28-day cycle, you can count back 14 days from when you expect your next period to begin. Knowing when you ovulated will give an idea of when you possibly got pregnant.

With a regular 28-day cycle, your fertile window will be 2 days before day 14. That means days 12, 13, and 14 are your most fertile days. The chances of you getting pregnant after unprotected sex on these days are high.

Knowing your fertile window will give you an idea of when you get pregnant.

Why isn’t Pregnancy Calculated from Conception? 

There has been a wide misconception about how pregnancy is calculated. Pregnancy can be calculated using different methods but the most common way is through your LMP. Your LMP is your last menstrual period

Pregnancy is widely calculated from the first day of your last menstrual period (LMP) that is, two weeks before ovulation. 

It is an easy calculation that helps you to know when you got pregnant as most times, most women don’t. 

This calculation is based on a regular menstrual cycle that occurs after 28 days which also greatly determines the 14 days ovulation period after menstruation.  

So what about an irregular menstrual cycle? 

Our calculator makes it easier for you to calculate using your actual menstruation date and that of your ovulation. This means an irregular menstrual cycle can also be calculated

Your menstrual cycle basically, allows more accurate details of your conception date and that is why it is mostly used. 

It helps to know the exact date of your fertile window which is the 12th, 13th, or 14th days of a 28 days cycle after your period as we’ve earlier stated. 

So, since most conception dates are not known, a quick rundown of your last menstrual period (LMP) gives a more detailed conception date. 

Can I Figure Out When I Got Pregnant Based on When I Had Intercourse?

Figuring out exactly when you got pregnant based on when you had sexual intercourse can be difficult. This is because your egg is only available for fertilization for one day. 

Conception is a complicated process that involves different factors. Just like we said earlier, sperm can live in a woman’s reproductive organ for up to 5 days after sexual intercourse. This makes it difficult to say exactly when you got pregnant (especially if you have more than one partner).

You will likely get an unreliable result if you calculate when you got pregnant from when you had intercourse. That is why we created this calculator.

This calculator helps you to discover when you got pregnant in seconds with a few clicks. 

Pregnancy is a beautiful experience, and children are blessings. However, understanding your menstrual cycle and how pregnancy works can help you prevent unplanned pregnancy.

If my baby is due in January when did I Get Pregnant?

In the First Week of January

If my baby is due in the first week of January when did I conceive?

  • If your baby stayed for 39 weeks, you likely conceived in the fourth week of May of the previous year.
  • If your baby stayed for 40 weeks, you likely conceived in the third week of May of the previous year.
  • If your baby stayed for 41 weeks, you likely conceived in the second week of May of the previous year.

In the Second week of January

If my baby is due in the second week of January when did I conceive?

  • If your baby stayed for 39 weeks, you likely conceived in the second week of May of the previous year.
  • If your baby stayed for 40 weeks, you likely conceived in the first week of May of the previous year.
  • If your baby stayed for 41 weeks, you likely conceived in the fourth week of April of the previous year.

In the Third week of January

If my baby is due in the third week of January when did I conceive?

  • If your baby stayed for 39 weeks, you likely conceived in the third week of May of the previous year.
  • If your baby stayed for 40 weeks, you likely conceived in the second week of May of the previous year.
  • If your baby stayed for 41 weeks, you likely conceived in the first week of May of the previous year.

In the Fourth week of January

If my baby is due in the fourth week of January when did I conceive?

  • If your baby stayed for 39 weeks, you likely conceived in the fourth week of May of the previous year.
  • If your baby stayed for 40 weeks, you likely conceived in the third week of May of the previous year.
  • If your baby stayed for 41 weeks, you likely conceived in the second week of May of the previous year.

If my baby is due in February when did I Get Pregnant?

In the First Week of February

If my baby is due in the first week of February when did I conceive?

  • If your baby stayed for 39 weeks, you likely conceived in the fourth week of May of the previous year.
  • If your baby stayed for 40 weeks, you likely conceived in the third week of May of the previous year.
  • If your baby stayed for 41 weeks, you likely conceived in the second week of May of the previous year.

In the Second Week of February

If my baby is due in the Second week of February when did I conceive?

  • If your baby stayed for 39 weeks, you likely conceived in the first week of June of the previous year.
  • If your baby stayed for 40 weeks, you likely conceived in the last week of May of the previous year.
  • If your baby stayed for 41 weeks, you likely conceived in the third week of May of the previous year.

In the Third Week of February

If my baby is due in the Third week of February when did I conceive?

  • If your baby stayed for 39 weeks, you likely conceived in the second week of June of the previous year.
  • If your baby stayed for 40 weeks, you likely conceived in the first week of June of the previous year.
  • If your baby stayed for 41 weeks, you likely conceived in the last week of May of the previous year.

In the Fourth Week of February

If my baby is due in the Fourth week of February when did I conceive?

  • If your baby stayed for 39 weeks, you likely conceived in the third week of June of the previous year.
  • If your baby stayed for 40 weeks, you likely conceived in the second week of June of the previous year.
  • If your baby stayed for 41 weeks, you likely conceived in the first week of June of the previous year.

If my baby is due in March when did I Get Pregnant?

In the First Week of March

If my baby is due in the First week of March when did I conceive?

  • If your baby stayed for 39 weeks, you likely conceived in the fourth week of June of the previous year.
  • If your baby stayed for 40 weeks, you likely conceived in the third week of June of the previous year.
  • If your baby stayed for 41 weeks, you likely conceived in the second week of June of the previous year.

In the Second Week of March

If my baby is due in the Second week of March when did I conceive?

  • If your baby stayed for 39 weeks, you likely conceived in the third week of June of the previous year.
  • If your baby stayed for 40 weeks, you likely conceived in the second week of June of the previous year.
  • If your baby stayed for 41 weeks, you likely conceived in the first week of June of the previous year.

In the Third Week of March

If my baby is due in the Second week of March when did I conceive?

  • If your baby stayed for 39 weeks, you likely conceived in the second week of July of the previous year.
  • If your baby stayed for 40 weeks, you likely conceived in the first week of July of the previous year.
  • If your baby stayed for 41 weeks, you likely conceived in the fourth week of June of the previous year.

In the Fourth Week of March

If my baby is due in the Second week of March when did I conceive?

  • If your baby stayed for 39 weeks, you likely conceived in the third week of July of the previous year.
  • If your baby stayed for 40 weeks, you likely conceived in the second week of July of the previous year.
  • If your baby stayed for 41 weeks, you likely conceived in the first week of July of the previous year.

If my baby is due in April when did I Get Pregnant?

In the First Week of April:

If my baby is due in the First week of April when did I conceive?

  • If your baby stayed for 39 weeks, you likely conceived in the fifth week of July of the previous year.
  • If your baby stayed for 40 weeks, you likely conceived in the fourth week of July of the previous year.
  • If your baby stayed for 41 weeks, you likely conceived in the third week of July of the previous year.

In the Second Week of April:

If my baby is due in the Second week of April when did I conceive?

  • If your baby stayed for 39 weeks, you likely conceived in the fourth week of July of the previous year.
  • If your baby stayed for 40 weeks, you likely conceived in the third week of July of the previous year.
  • If your baby stayed for 41 weeks, you likely conceived in the second week of July of the previous year.

In the Third Week of April:

If my baby is due in the Third week of April when did I conceive?

  • If your baby stayed for 39 weeks, you likely conceived in the third week of July of the previous year.
  • If your baby stayed for 40 weeks, you likely conceived in the second week of July of the previous year.
  • If your baby stayed for 41 weeks, you likely conceived in the first week of July of the previous year.

In the Fourth Week of April:

If my baby is due in the Fourth week of April when did I conceive?

  • If your baby stayed for 39 weeks, you likely conceived in the second week of July of the previous year.
  • If your baby stayed for 40 weeks, you likely conceived in the first week of July of the previous year.
  • If your baby stayed for 41 weeks, you likely conceived in the fifth week of June of the previous year.

If my baby is due in May when did I Get Pregnant?

In the First Week of May

If my baby is due in the First week of May when did I conceive?

  • If your baby stayed for 39 weeks, you likely conceived in the fourth week of August of the previous year.
  • If your baby stayed for 40 weeks, you likely conceived in the third week of August of the previous year.
  • If your baby stayed for 41 weeks, you likely conceived in the second week of August of the previous year.

In the Second Week of May:

If my baby is due in the Second week of May when did I conceive?

  • If your baby stayed for 39 weeks, you likely conceived in the first week of September of the previous year.
  • If your baby stayed for 40 weeks, you likely conceived in the fourth week of August of the previous year.
  • If your baby stayed for 41 weeks, you likely conceived in the third week of August of the previous year.

In the Third Week of May:

If my baby is due in the Third week of May when did I conceive?

  • If your baby stayed for 39 weeks, you likely conceived in the second week of September of the previous year.
  • If your baby stayed for 40 weeks, you likely conceived in the first week of September of the previous year.
  • If your baby stayed for 41 weeks, you likely conceived in the fourth week of August of the previous year.

In the Fourth Week of May:

If my baby is due in the Fourth week of May when did I conceive?

  • If your baby stayed for 39 weeks, you likely conceived in the third week of September of the previous year.
  • If your baby stayed for 40 weeks, you likely conceived in the second week of September of the previous year.
  • If your baby stayed for 41 weeks, you likely conceived in the first week of September of the previous year.

If my baby is due in June when did I Get Pregnant?

In the First Week of June

If my baby is due in the First week of June when did I conceive?

  • If your baby stayed for 39 weeks, you likely conceived in the fourth week of September of the previous year.
  • If your baby stayed for 40 weeks, you likely conceived in the third week of September of the previous year.
  • If your baby stayed for 41 weeks, you likely conceived in the second week of September of the previous year.

In the Second Week of June:

If my baby is due in the Second week of June when did I conceive?

  • If your baby stayed for 39 weeks, you likely conceived in the first week of October of the previous year.
  • If your baby stayed for 40 weeks, you likely conceived in the fourth week of September of the previous year.
  • If your baby stayed for 41 weeks, you likely conceived in the third week of September of the previous year.

In the Third Week of June:

If my baby is due in the Third week of June when did I conceive?

  • If your baby stayed for 39 weeks, you likely conceived in the second week of October of the previous year.
  • If your baby stayed for 40 weeks, you likely conceived in the first week of October of the previous year.
  • If your baby stayed for 41 weeks, you likely conceived in the fourth week of September of the previous year.

In the Fourth Week of June:

If my baby is due in the Fourth week of June when did I conceive?

  • If your baby stayed for 39 weeks, you likely conceived in the third week of October of the previous year.
  • If your baby stayed for 40 weeks, you likely conceived in the second week of October of the previous year.
  • If your baby stayed for 41 weeks, you likely conceived in the first week of October of the previous year.

If my baby is due in July when did I Get Pregnant?

In the First Week of July

If my baby is due in the First week of July when did I conceive?

  • If your baby stayed for 39 weeks, you likely conceived in the fourth week of October of the previous year.
  • If your baby stayed for 40 weeks, you likely conceived in the third week of October of the previous year.
  • If your baby stayed for 41 weeks, you likely conceived in the second week of October of the previous year.

In the Second Week of July:

If my baby is due in the Second week of July when did I conceive?

  • If your baby stayed for 39 weeks, you likely conceived in the first week of November of the previous year.
  • If your baby stayed for 40 weeks, you likely conceived in the fourth week of October of the previous year.
  • If your baby stayed for 41 weeks, you likely conceived in the third week of October of the previous year.

In the Third Week of July:

If my baby is due in the Third week of July when did I conceive?

  • If your baby stayed for 39 weeks, you likely conceived in the second week of November of the previous year.
  • If your baby stayed for 40 weeks, you likely conceived in the first week of November of the previous year.
  • If your baby stayed for 41 weeks, you likely conceived in the fourth week of October of the previous year.

In the Fourth Week of July:

If my baby is due in the Fourth week of July when did I conceive?

  • If your baby stayed for 39 weeks, you likely conceived in the third week of November of the previous year.
  • If your baby stayed for 40 weeks, you likely conceived in the second week of November of the previous year.
  • If your baby stayed for 41 weeks, you likely conceived in the first week of November of the previous year.

If my baby is due in August when did I Get Pregnant?

In the First Week of August:

If my baby is due in the First week of August when did I conceive?

  • If your baby stayed for 39 weeks, you likely conceived in the fourth week of November of the previous year.
  • If your baby stayed for 40 weeks, you likely conceived in the third week of November of the previous year.
  • If your baby stayed for 41 weeks, you likely conceived in the second week of November of the previous year.

In the Second Week of August:

If my baby is due in the Second week of August when did I conceive?

  • If your baby stayed for 39 weeks, you likely conceived in the first week of December of the previous year.
  • If your baby stayed for 40 weeks, you likely conceived in the fourth week of November of the previous year.
  • If your baby stayed for 41 weeks, you likely conceived in the third week of November of the previous year.

In the Third Week of August:

If my baby is due in the Third week of August when did I conceive?

  • If your baby stayed for 39 weeks, you likely conceived in the second week of December of the previous year.
  • If your baby stayed for 40 weeks, you likely conceived in the first week of December of the previous year.
  • If your baby stayed for 41 weeks, you likely conceived in the fourth week of November of the previous year.

In the Fourth Week of August:

If my baby is due in the Fourth week of August when did I conceive?

  • If your baby stayed for 39 weeks, you likely conceived in the third week of December of the previous year.
  • If your baby stayed for 40 weeks, you likely conceived in the second week of December of the previous year.
  • If your baby stayed for 41 weeks, you likely conceived in the first week of December of the previous year.

If my baby is due in September when did I Get Pregnant?

In the First Week of September:

If my baby is due in the First week of September, when did I conceive?

  • If your baby stayed for 39 weeks, you likely conceived in the fourth week of December of the previous year.
  • If your baby stayed for 40 weeks, you likely conceived in the third week of December of the previous year.
  • If your baby stayed for 41 weeks, you likely conceived in the second week of December of the previous year.

In the Second Week of September:

If my baby is due in the Second week of September, when did I conceive?

  • If your baby stayed for 39 weeks, you likely conceived in the first week of January this year.
  • If your baby stayed for 40 weeks, you likely conceived in the fourth week of December of the previous year.
  • If your baby stayed for 41 weeks, you likely conceived in the third week of December of the previous year.

In the Third Week of September:

If my baby is due in the Third week of September, when did I conceive?

  • If your baby stayed for 39 weeks, you likely conceived in the second week of January this year.
  • If your baby stayed for 40 weeks, you likely conceived in the first week of January this year.
  • If your baby stayed for 41 weeks, you likely conceived in the fourth week of December of the previous year.

In the Fourth Week of September:

If my baby is due in the Fourth week of September, when did I conceive?

  • If your baby stayed for 39 weeks, you likely conceived in the third week of January this year.
  • If your baby stayed for 40 weeks, you likely conceived in the second week of January this year.
  • If your baby stayed for 41 weeks, you likely conceived in the first week of January this year.

If my baby is due in October when did I Get Pregnant?

In the First Week of Ocotber

If my baby is due in the First week of October when did I conceive?

  • If your baby stayed for 39 weeks, you likely conceived in the fourth week of January this year.
  • If your baby stayed for 40 weeks, you likely conceived in the third week of January this year.
  • If your baby stayed for 41 weeks, you likely conceived in the second week of January this year.

In the Second Week of Ocotber

If my baby is due in the Second week of October when did I conceive?

  • If your baby stayed for 39 weeks, you likely conceived in the first week of February this year.
  • If your baby stayed for 40 weeks, you likely conceived in the fourth week of January this year.
  • If your baby stayed for 41 weeks, you likely conceived in the third week of January this year.

In the Third Week of Ocotber

If my baby is due in the Third week of October when did I conceive?

  • If your baby stayed for 39 weeks, you likely conceived in the second week of February this year.
  • If your baby stayed for 40 weeks, you likely conceived in the first week of February this year.
  • If your baby stayed for 41 weeks, you likely conceived in the fourth week of January this year.

In the Fourth Week of Ocotber

If my baby is due in the Fourth week of October when did I conceive?

  • If your baby stayed for 39 weeks, you likely conceived in the third week of February this year.
  • If your baby stayed for 40 weeks, you likely conceived in the second week of February this year.
  • If your baby stayed for 41 weeks, you likely conceived in the first week of February this year.

If my baby is due in November when did I Get Pregnant?

In the First Week of November:

If my baby is due in the First week of November when did I conceive?

  • If your baby stayed for 39 weeks, you likely conceived in the fourth week of February this year.
  • If your baby stayed for 40 weeks, you likely conceived in the third week of February this year.
  • If your baby stayed for 41 weeks, you likely conceived in the second week of February this year.

In the Second Week of November:

If my baby is due in the Second week of November when did I conceive?

  • If your baby stayed for 39 weeks, you likely conceived in the first week of March this year.
  • If your baby stayed for 40 weeks, you likely conceived in the fourth week of February this year.
  • If your baby stayed for 41 weeks, you likely conceived in the third week of February this year.

In the Third Week of November:

If my baby is due in the Third week of November when did I conceive?

  • If your baby stayed for 39 weeks, you likely conceived in the second week of March this year.
  • If your baby stayed for 40 weeks, you likely conceived in the first week of March this year.
  • If your baby stayed for 41 weeks, you likely conceived in the fourth week of February this year.

In the Fourth Week of November:

If my baby is due in the Fourth week of November when did I conceive?

  • If your baby stayed for 39 weeks, you likely conceived in the third week of March this year.
  • If your baby stayed for 40 weeks, you likely conceived in the second week of March this year.
  • If your baby stayed for 41 weeks, you likely conceived in the first week of March this year.

If my baby is due in December when did I Get Pregnant?

In the First Week of December:

If my baby is due in the First week of December when did I conceive?

  • If your baby stayed for 39 weeks, you likely conceived in the fourth week of March this year.
  • If your baby stayed for 40 weeks, you likely conceived in the third week of March this year.
  • If your baby stayed for 41 weeks, you likely conceived in the second week of March this year.

In the Second Week of December:

If my baby is due in the Second week of December when did I conceive?

  • If your baby stayed for 39 weeks, you likely conceived in the first week of April this year.
  • If your baby stayed for 40 weeks, you likely conceived in the fourth week of March this year.
  • If your baby stayed for 41 weeks, you likely conceived in the third week of March this year.

In the Third Week of December:

If my baby is due in the Third week of December when did I conceive?

  • If your baby stayed for 39 weeks, you likely conceived in the second week of April this year.
  • If your baby stayed for 40 weeks, you likely conceived in the first week of April this year.
  • If your baby stayed for 41 weeks, you likely conceived in the fourth week of March this year.

In the Fourth Week of December:

If my baby is due in the Fourth week of December when did I conceive?

  • If your baby stayed for 39 weeks, you likely conceived in the third week of April this year.
  • If your baby stayed for 40 weeks, you likely conceived in the second week of April this year.
  • If your baby stayed for 41 weeks, you likely conceived in the first week of April this year.

In all,

getting pregnant can be a complicated and unpredictable process, and it is not always easy to determine exactly when it happened. However, understanding your menstrual cycle, fertile window, and timing of unprotected sex can help you narrow down the potential dates. Utilizing tools like the “when I got pregnant calculator” can also provide additional guidance and support during an unplanned pregnancy. Ultimately, seeking advice from a healthcare provider can ensure that you receive the necessary care and support throughout your pregnancy journey.