Baby measuring 2 weeks ahead on US

kstokes2002

At my 20 week ultrasound, the my baby measured about 2 weeks ahead.... I had another scheduled ultrasound yesterday and again, he measured 2 weeks and 3 days ahead. Anyone else have big measurements? (my fundal height is perfect for my date though). Any second time moms have their babies early b/c of this? I have a very small frame, 5'5 and 114 before baby so I'm concerned --- my husband is 6'3 and about 250 pounds so I sort of expected it! lol.