Expected Date of Delivery

When am I due? When is the d-day?

• Every pregnant women asks this question. The doctors refers to the due date as EDD. This means the Expected Date of Delivery. It helps the mother to plan herself for child birth and also for the new arrival in her life.
• The EDD may prove correct only in 50% of expectant mothers. If your menstrual cycles have been regular and of a 28 days duration, you will probably deliver close to your estimated date. If they have been of a longer duration, you are likely to go beyond your EDD, and in case of irregular cycles the due date does not work at all, then a ultrasonogram in pregnancy will be a better indicator.

Determination of Due Date
Pregnancy lasts for 40 weeks from the first day of your last menstrual cycle or 38 weeks after your conception.

Based on LMP (Last Menstrual Period)
If the cycles have been regular of 28 days duration, then add 9 months 7 days to the first day of your last menstrual cycle. e.g.  if the LMP is 1st January, then EDD will be 8th October. This is the most commonly used method.

Other  Methods  of  Calculation  of  EDD

A.	Based on Conception Probably does not work out for most women.
B.	Based on Abdominal Examination The size of the uterus, can sometimes accurately determine the period of gestation.
C.	Ultrasonography This method is the most accurate, for the doctor can measure the baby’s various parts in the USG (Ultrasonography), which helps in estimating the stage of foetal development and consequently the due date.