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# How to Calculate Date of Conception?

How to Calculate Date of Conception From Last Menstrual Period (LMP)?

## Calculate Date of Conception From Last Menstrual Period

Conception is the date or time when an offspring had formed inside the womans body. It was the date or time when the 1st cell of your baby had formed. Scientifically, it was the exact date when the sperm met the egg after ovulation and entered the egg to form the foetus.

Usually sperm can live for 3 to 5 days inside womans body awaiting the egg. Hence even if you had an intercourse 3-5 days before ovulation, you still have a high chance of conceiving a baby.

This is a simple, useful and short tutorial to find the Date of Conception. Date of Conception can be defined as the probable sexual intercourse date that lead to the pregnancy. This tutorial calculates the date of conception based on an average 28 day menstrual cycle for women.

Most of the time we do not remember the date of intercourse (date of conception), which will be useful in calculating the Estimated Due Date of Delivery. But using LMP (Last Menstrual Period), we could find out the Pregnancy Due Date as well as the possible date of conception (date of intercourse). This tutorial will assist you to know how to calculate conception date from last period.

Formula: Possible Dates of Conception:
This tutorial calculates the probable date of conception based on the LMP (Last Menstrual Period) considering the menstrual period to be a regular 28 days cycle.

Possible Dates of Conception (PDC) = (PDO - 4 days) to (PDO + 4 days)
PDO (Probable Date of Ovulation) = 1st day of LMP + 14 days

Where,
LMP is Last Menstrual Period

Finding Possible Dates of Conception: Example:
Consider the below example. Find the possible dates of conception, where the first day of LMP (Last Menstrual Period) was July 5, 2016.

PDO (Probable Date of Ovulation)
= July 5, 2016 + 14 days
= July 19, 2016

PDC (Possible Dates of Conception)
= (July 19, 2016 - 4 days) to (July 19, 2016 + 4 days)
= July 15, 2016 to July 23, 2016

Hence the possible dates of conception for the given LMP should be probably between July 15, 2016 and July 23, 2016.

The EDD (Estimated Due Date of Delivery) could also be calculated with the given 1st day of LMP, which is 40 weeks from the start of last menstrual period.

EDD (Estimated Due Date of Delivery)
= 280 days + 1st Day of LMP
= April 11, 2017

The Date of Conception could also be determined using the EDD (Estimated Due Date of Delivery). Click on the below link to know in detail.

Finding Date of Conception using EDD (Estimated Due Date of Delivery)