How long is it until morning sickness starts?

May not: If you have morning sickness, it usually starts in the first month or two of pregnancy. Not all women will experience this; it's not required!

4-6 wks: Could be as early as 4-6 wks as this is when HCG levels start to rise.

5-6 weeks: Usually, morning sickness, that can occur at any part of the day or night doesn't occur until after 6 weeks when rising Progesterone levels approach "nausea causing" levels.