Hello,
Welcome to the forum. Gestational age is the age of an embryo or fetus. While calculating gestational age, we
normally count it from the last menstrual period. Some doctors count gestational age from fertilization
instead of LMP. This method of counting is also known as fertilization age and is usually greater by about
two weeks. So the doctor might be counting the gestational age by this method. Secondly, another method to
calculate current gestational age is to use a tape measure to determine the distance from the pubic bone up
over the top of the uterus to the very top. That distance, measured in centimeters, is approximately equal to
the weeks of gestation, from about mid-pregnancy until nearly the end of pregnancy. This is known as
MacDonald's Rule. At 9 weeks of gestation, ultrasound of the uterus is the best method to get a correct
estimation of the gestational age. Measurement of a crown-rump length during the first trimester (1-13 weeks)
will give a gestational age that is usually accurate to within 3 days of the actual due date. It will also
clear any doubts about the gestational age because it is the most accurate method of calculating it rather
than digital pregnancy tests or manual examination. So my sincere advice is to get an ultrasound done for the
correct gestational age. If the gestational age is lagging by two weeks , then it can cause IUGR( intrauterine
growth retardation). So to prevent this regular ultrasounds need to be done. I hope it helps. Take care and
please do keep us posted in case you have any additional doubts. Kind regards.
