[whitelady888]

Is the age of gestation (after the baby was born) written on a baby's pink or blue tag in the nursery room accurate? It's suppose to tell when the mother got pregnant, but is it accurate as in 99% or is it just a rough estimation? How can they tell the aog after birth with matching days of the infant?!

[Jolie]

Gestational age of a newborn infant can be determined in a number of ways, including the date of mother's last period, estimated by fetal growth assessed by ultrasound during pregnancy, or examination of the infant after delivery.

Each method has its strengths and drawbacks, but determining an accurate gestational age by combining 2 or more methods is usually not a problem.

[Elvish]

I wouldn't go so far as to use a percentage of time that it's accurate.

Ultrasounds are only as good as the person performing them, the person interpreting, and the little rascal inside cooperating to get all the measurements. The further along in the pregnancy the u/s is performed, the less accurate it is at determining gestational age.

LMP estimation is alright IF mom is a good historian and has had fairly regular periods.

But nothing is foolproof. Lots of times we get a baby that was born after a 'post-dates' induction that looks MAYBE 38 weeks. Or a mom who comes in thinking she 'might be' about 36-37 weeks that has peeling skin, pendulous scrotum, GREAT tone, and big breast buds. Yeah, maybe 36 weeks and then some.....

It's not an exact science.