Probably 8 weeks.
Actually at 8 weeks pregnant the fetus would only be 6 weeks old.
For the first 8 weeks the developing human is called an embryo after that it is called a fetus.
Fetus
fetus
10 weeks
29 weeks
17.5mm
After 8 weeks
Usually this is not possible condition for a fetus
8 weeks
8 weeks
i had a sonogram yesterday and the sac could be seen but no fetus what does this mean
The embryo weighs 1 gram between 5-8 weeks. A fetus is far bigger than one gram.