I am a female, and I am primigravida (17 weeks and 6 days). According to my LMP, I am 17 weeks and 6 day pregnant but according to my NT scan (done in 12-13 week )-gestation period showing pregnancy of 18 weeks and 3 days till date. Now I have to go for level two ultrasound, and my doctor gave me the date of next month. Will it be fine by this time to go for an ultrasound or late according to my gestation period? As I heard that it should be done between 18 to 20 weeks.