Conversation: The conversation between human and AI assistant.
[|Human|] The start of my last menstural period was Oct 25 2010. Lasted about 7 days. According to that, I m supposed to be 12 weeks today (Jan 15 2011). However, I went for my dating ultrasound yesterday and was told I was only 10 weeks and 6 days. Therefore they couldn t do the Nuchal Translucency scan. My question is, what exactly is gestational age? Does this calculate when the baby was concieved? And if so, the baby would have been concieved the last day of my period (Unlikely, I thought?) I m confused as to which age I should be using. If my gestational age was different, shouldn t everybody else s be? I hear people say I was only off by 2 or 3 days , but wouldn t that mean they also concieved during their period? Please help.
[|AI|]  Hallow Dear, The gestational age of the baby is in fact the actual age of the baby. Naturally it is from the day of conception. However, it is not possible in day to day life to locate the day of conception. Hence, it is customary to calculate the day of expected due date of delivery or even the duration of pregnancy from the date of last menstrual period. This is the clinical way of assessing the duration of pregnancy. Total duration of pregnancy which is said 280 days is counted from the date of last menstrual period. Ultrasound calculates the duration of pregnancy according to the measurements of the baby. It has some error factor ranging from 2 weeks to few days depending upon the stage and duration of pregnancy. I hope this gives you clear knowledge about the age of the baby.