I counted my days on the calendar and each month i counted out four weeks. I am 21 weeks and i am do August 30 and according to my due date i am five months and i just started my six month at 21weeks. Besides my doctor told me i was half way there and i have 20 weeks to go.
The picture I go by says 18-21 is five months and 22 to 26 is six months.
As far as I know 20weeks is 5 months