This is the publisher's blurb that is written on the back of the book:

"These days, Anita Blake is less interested in vampire politics than in an ancient, ordinary dread she shares with women down the ages: she may be pregnant. And, if she is, whether the father is a vampire, a werewolf, or someone else entirely, she knows perfectly well that being a Federal Marshal known for raising the dead and being a vampire executioner, is no way to bring up a baby."

"Anita Blake should be concentrating on a dangerous situation: the ardeur, the sexual power that flows between Anita and Jean-Claude, Master Vampire of the City - and Richard, the volatile werewolf who loves her passionately - is reaching new levels, perhaps evolving into something entirely new. It seems to be choosing new lovers for Anita, acting with a will of its own. The unexpected effect of this is that Jean-Claude's own powers as a Master Vampire have grown to new levels - and Richard, always unpredictable, is changing too. However, as the days pass Anita finds herself less interested in vampire politics than in an altogether more personal concern. She may be pregnant. And if she is, whether the father is a vampire, a werewolf or something else entirely, she knows full well that being a Federal Marshall, known for raising the dead and executing vampires, is no way to bring up a baby."
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A brief synopsis:
(May contain SPOILERS so if you don't want to know, don't read them!)

St. Louis hosts a gathering of Masters from all over the United States for the performance of a new all-vampire dance troupe. Anita is acutely nervous about so many Masters close at hand who might smell weakness in Jean-Claude's kiss. She must also find another pomme de sang to feed her ardeur. On top of everything else, she has another, more normal but still frightening worry: she may be pregnant.
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