Strategy for revealing pregnancy to new department/department chair I am a new tenure-track assistant professor who is expecting a baby in January (just after spring semester starts). I will be arriving on campus in the next couple of weeks and need to tell my department chair I am pregnant quite soon, as the teaching assignments for spring classes will be made shortly. 

I am assuming that I will not get any leave and I will need to teach my spring class, either in person or online. This is because I am in the US, and FMLA (Family and Medical Leave Act) protections don't apply until one has been employed for a year and the university doesn't offer anything beyond what is required by FMLA. 

My current strategy is to shoot the chair an email mentioning that I am on campus now and that I hope we can meet before the semester starts. During the meeting I plan to be straightforward and tell her I am expecting. I will tell her I am hoping to stop my tenure clock for a year and ask her to strategize with me on how to meet my teaching obligation in the spring, given that I will be due around the second week of classes.

What are the most important considerations when having this type of conversation with my chair? My main concern is my reputation in the department. I don't want to make a bad first impression, and I worry that some people might perceive this  unexpected turn of events negatively. 

Update: I took the advice here and met with the chair about a week after I got to campus. I emphasized my commitment to my various projects and my plan for not losing momentum. She took everything in stride. Although I didn’t get a teaching release, she arranged for me to teach an online class where most of the work happens in the second half of the quarter in order to meet my teaching obligations during the quarter when I gave birth. This put me back to work at about 4 weeks postpartum, but I could do it all from home. Ultimately, I still tried to forefront my work in work conversations. I don’t think that the pregnancy affected my reputation in the department.
I don't think that when and how you reveal your pregnancy (as long as its professional) will have much impact on your career, especially compared to the fact of being pregnant and having another child.

I would advise meeting with the department head as soon as possible and reiterating your long-term commitment to the department. You two have the same long-term goal: your being a successful assistant professor and earning tenure. It is in your department head's interest to be helpful to you.

Before going into the meeting, I would decide what I wanted. You mention wanting to stop your tenure clock for a year. Do you want an unpaid leave if possible? While it is good to be flexible, it is also good to know and communicate what your best outcome would be, in case they can accommodate you.

One outside-the-box solution might be if you could defer the start of your assistant professorship for a year and teach your fall course(s) as an adjunct.

If you have started thinking about grant applications or other things of interest to the department head, it would be fine to also talk about those at the meeting.

Good luck!