6 months = 22-26 weeks
7 months = 27-31 weeks
8 months = 32-35 weeks
9 months = 36-40 weeks
The months are separated a different way due to some months having 5 week not 4, months aren't separated by 4 weeks or we'd be preggers for 10 months :P
Hope this helps
6 months and 3 weeks. You will be 7 months at 28 weeks