Congrats!!! I had my second baby 4 months ago! I told my clients just after 3 months. The most important thing is for you to have your plan all set before you tell them!!!! Outline how you will handle appointments, when you will close and for how long etc. You may have to prepare yourself to lose clients. All of my kids stayed on until the bitter end....which I really enjoyed as it made the time pass quickly! I had a small group and my Mom was able to cover me for all my appointments which my clients loved! We actually took the opportunity to move at the same time so I closed the daycare and will just be starting over in our new neighborhood. Make sure to take care of yourself as time goes on....you will get tired and it's not the end of the world if the kids get more free play time! Good luck with everything!!