I just offended my friend

You must have been stressed out at the time, so you must have said some stuff. Although just because you are stressed out wasn't a reason for you to go on to her like that, and seeing it wasn't her fault, you should really apologies. Well obviously that's going to be pretty hard as she is ignoring your phone calls, but maybe you could visit her? Actually, ask her to meet up infront of a coffee place, some place in public so you can talk it over, just to be safe and make sure things won't happen at her house if she tries to fight or something.

Yes just wait for your friend to cool off surely time heals & he/she will miss you its just a test how strong your friendship is. When you can finally talk to him/her just make him/her feel that you deeply regret it.

Try to talk to her or write her a letter that you are just stressed out and of course you are pregnant. Pregnant women usually are moodier because of the hormones, right? I think in time she will understand. I admit there are times that I regretted what I said to someone because those where times that my emotions got the best of me however I'm glad that I'm still friends with those people that I have offended. I said sorry to them and in time they have forgiven me. Time heals all wounds so they say.

first of all.. CONGRATULATIONS for the birth of your new baby!!

i feel sorry for both you and your friend..
but i dont understand how come u didnt brief ur replacement directly instead of going to your boss - unless it was the boss who insisted you briefed him directly.
i mean, if he was the one insisted - he should've taken the time to pass on the info to your friend instead of telling her to call and ask u..
you are on maternity leave - i dont think your friend is 'avoiding' you - she probably realized that she caught you at a 'bad time', and probably she's just too busy with her own work to answer your calls...
if she really is 'sulking' and avoiding - try to get a '3rd.party' to help remedy the situation..