Gestational refers to dating from the LMP and developmental refers to conception or what is seen on the ultrasound. Well, another variable is the length of menses but everyone has a first day so to be consistent, that is the marker used. Have you been under any stress lately? Whether you're trying to avoid being very pregnant in the middle of summer or are a teacher who wants to maximize time off with your little one, you can try to time when you conceive in order to "plan" your due date. The gestational age should ,therefore, be at least 10 to 12 weeks if fetal heart tone are heard. I agree with what you said about dating pregnancy — your quotes are what I was trying to say in the post.
An obvious marker is the first day of the last menstrual period LMP.
Due Date Calculator
However, I am still trying to calculate the date of conception. The ultrasound counts from conception which is 2 weeks later. The table below shows the average age of infants delivered in the United States according to the number of fetuses being carried plurality . Even if the bleeding was just a side effect of intercourse or something else not related to implantationyou might still be pregnant. Can my due date change?