Broken (Women of the Otherworld #6) by Kelley Armstrong

Elena is going stir crazy. Why?  Her pack mates won't let her leave their sight.  Elena is the only known female werewolf and she is pregnant.  That can be dangerous in the supernatural world.

However, work must go on and she is needed to retrieve a letter that is believed to be written by Jack the Ripper.  The job seems easy and would provide a much needed distraction.  Who would have thought the letter contains a portal that releases zombies, cholera, typhus and possibly Jack the Ripper himself.  Anything that can go wrong does as the pack attempts to close the portal and set the city of Toronto right.

 Broken is not the best of the Women of the Otherworld series but still worth the read.