Pregnancy dating ultrasound calculator
The date of LMP is known by most women so doctors use this date as a starting point for pregnancy.
From your LMP they will add 280 days and this will give your Personal timeline for your Pregnancy - Print out and Keep a copy in your purse!
Every pregnancy is unique and your baby will come when it's ready.
Be sure to talk to your health care provider about your due date.
THIS INFORMATION IS NOT INTENDED TO REPLACE CLINICAL JUDGMENT OR GUIDE INDIVIDUAL PATIENT CARE IN ANY MANNER.
Gestational age (or menstrual age) is a measure of the age of a pregnancy which is taken from the woman's last menstrual period (LMP), or the corresponding age of the gestation as estimated by a more accurate method if available.
All information contained in and produced by the EBMcalc system is provided for educational purposes only.
The first two weeks of your pregnancy includes the time of your period, ovulation and fertilization.
Such methods include adding 14 days to a known duration since fertilization (as is possible in in vitro fertilization), or by obstetric ultrasonography.
The popularity of using such a definition of gestational age is that menstrual periods are essentially always noticed, while there is usually a lack of a convenient way to discern when fertilization occurred.
On average only 5% of births take place exactly on the estimated due date.
Most are born within a week either side of the estimated due date.For example, if there is a gestational age based on the beginning of the last menstrual period of 9.0 weeks, and a first-trimester obstetric ultrasonography gives an estimated gestational age of 10.0 weeks (with a 2 SD variability of ±8% of the estimate thereby giving a variability of ±0.8 weeks), the difference of 1.0 weeks between the tests is larger than the 2 SD variability of the ultrasonography estimate, indicating that the gestational age estimated by ultrasonography should be used as the official gestational age.