Grey's Anatomy Season 9 Episode 13, "Bad Blood," will tell the story of Meredith's pregnancy as Seattle Grace Mercy West faces its worst challenge since losing some prized surgeons. Should Meredith be worried?

Meredith has lost a baby to miscarriage in the past. She couldn't bring herself to announce to anyone other than Derek that she is pregnant until after her first trimester. In a beautiful "friendship" scene, Cristina Yang tells Derek she knows Mer's pregnant, and she will tell her "when she's ready to be happy about it."

In Grey’s Anatomy Season 9 Episode 13, "Bad Blood," Meredith deals with a "flutter" while Derek tries to save the hospital -- with Kepner.

"There's a flutter," an anxious Meredith tells Bailey in an exclusive sneak peek video at Entertainment Weekly. Moms know this could be anything - or it could be the baby making its first movements inside mum's tummy. Perhaps Mer is just being Mer and her baby's doing just fine.

Grey's Anatomy Season 9X13 "Bad Blood" Synopsis

On TV.com, this is how this week's episode of Grey's Anatomy is described:

"As Derek and April work around the clock to find a solution for the hospital, Cristina struggles to respect the wishes of a family whose son is dying. Meanwhile, Arizona empathizes with a teenager who faces problems similar to her own."

Constance Zimmer returns in her recurring role as Dr. Alana Cahill. Viewers might find out why she's left her profession as a surgeon, and why she seems to downplay the E.R. (Granted, the hospital is in serious financial trouble, but there must be another way.)

Calzona and Crowen: New Chapters

Arizona of the Calzona duo will feel her patient in this week's episode. What sort of advice could she give now that she has just won against Phantom Limb Syndrome? Callie and Arizona are determined to never run, no matter the challenges. In last week's episode Arizona deemed it necessary to hide her pain from Callie. Things did work out in the end. They are both on a smoother way to recovery.

Crowen fans would like to see Cristina and Owen back together "officially." In their world, however, the divorce is their way to be together. Marriage was too much of a pressure for them. Now they can just enjoy each other without the drama. At least until they are pushed against the wall to really look into what they have. That is bound to happen, eventually.

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Arizona