Description OBS / Pregnancy Calculator

A Free easy to use calculator For an avid mother and a busy obstetrician to
know the important dates and duration of your pregnancy (POG plus EDD),
Time in weeks and days of your pregnancy.From only one date entry we
also calculate your expected date of delivery (EDD), which is also
calculated by an obstetrician in your first ante-natal visit. This Obs
calculator is very usefull to obstettrician who don't want to calculate
Expected Date of Dilevery (EDD), and Period of Gestation (POG) manually
and wants or needs a simple tool which only requires one entry. It uses
Parikh's formula for Asian countries accurate to Standard Deviation
13days), and Naegli's formulae for the western countries EDD (Standard
devaition 13days). Primigravida's (First time mothers) are within Plus
minus 7-9days of EDD.
it is helpful to consider gestation time as a
range of dates rather than as a single "due date". For instance, a
standard deviation of 13 days means that 90% of babies will be born
within two weeks of their EDD, and 21% will be born within three days
of it. Only 4% of births will occur on the EDD.
Refrences:
(1). Bergsjø P, Denman DW 3rd, Hoffman HJ, Meirik O. (1990). "Duration
of human singleton pregnancy. A population-based study.". Acta Obstet
Gynecol Scand: 197–207.
(2). Gray, H (1962). "Duration of pregnancy.". Stanford Medical
Bulletin 20: 24–8. PMID 13901307.
(3).Dr H. Kieler, O. Axelsson, S. Nilsson, U. Waldenströ (1995). "The
length of human pregnancy as calculated by ultrasonographic measurement
of the fetal biparietal diameter". Ultrasound in Obstetrics &
Gynecology 6 (5): 353–357. doi:10.1046/j.1469-0705.1995.06050353.x.
PMID 8590208.