How can I maintain intimacy with my partner in while pregnant?

There is so much.... More to intimacy than the physical side of your relationship. Sharing the pregnancy through open and honest communication will enhance the feelings of intimacy that you have for one another. Indeed, pregnancy and the raising of a family together can be an experience that draws two people together like no other. The physical side of intimacy is a natural extension of this closeness! Congratulations.
The same way. The same way you do before you became pregnant. Open and honest communication is key to maintaining and improving intimacy in relationships. If your partner has concerns about how your pregnancy affects sexual intimacy start a conversation about it.
Talk. The best way is to talk. Many moms fear that their partner will not find them sexy (often the opposite is true!) or partners fear they will harm the baby with sex. Talk about your fears to each other and discuss safety questions with your doc. Both of you will see your changing body in an exciting and different way during pregnancy.