Did you talk with her during your pregnancy? If so, I think this situation is really weird. How does telling her hurt him? What's the point of not telling her? If you haven't talked with her I suggest it's not unusual for her to not know and mentioning the baby now would not be a problem. Unless you call her after all this time. Then, a call would seem weird too.
So, if you haven't talked with her for 6-7 months I wouldn't call her now. It would seem like you're putting the baby in her face. Makes no sense to me to avoid her all this time and now want to be friends again. If I were her I would not consider you my friend.
If you have been talking with her, I'd tell her next time you talk that you have a baby and apologize for not having told her you were pregnant. Awkward; may hurt her feelings. You just accept that as a consequence for your decision. Don't try to convince her you had a good reason for not telling her.
Does your husband decide for you what you will and will not do with your friends? If so, I'd take this as a lesson to take charge of my life. Do you control his friendships? I bet not.
So she said some things about him he didn't like. So he doesn't have to see or talk with her. But if you like her then you can see and talk with her. You can respect his feelings by not talking about her. I'm not saying to keep the friendship secret. Just don't make her a conversation topic with him.
If the things she said and did to him were seriously out of line why do you still want her as a friend? Because he's so angry I wonder if what she said is too close to the truth. In which case I'd see her comments as trying to be supportive of me and I'd continue the friendship with some boundaries.