Maternity leave

With the job I gave in a salon as a cosmetologist, I am on my feet for 8-9 hours sometimes more everyday. I work 5 days a week. So I know I won't be able to work the whole pregnancy as it is also stressful at my job dealing with the public. But my question is to those who have already went on maternity leave with a strenuous job. When did you leave and how long did you take off before coming back? I have more flexibility in when I can do either but I just want other opinions.