Grey's Anatomy Grey's Anatomy

If ever there were a game-changer in a relationship, it would be Cristina's decision to abort her and Owen's child in the Grey's Anatomy season premiere.

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From the beginning of the ABC medical drama, Cristina (Sandra Oh

) has been dead-set against having children. She was pregnant with Dr. Burke's baby in Season 1, and was planning to have an abortion, but it resulted in an ectopic pregnancy. This time around, Cristina gave husband Owen (Kevin McKidd) no say in the decision, which will certainly cause a divide between them this season. Still, executive producer Shonda Rhimes promises, "The love is still there.""I didn't want to create situations this season where something happened and they broke up," she continues. "What's adult about this is to give our characters impossible situations and see how they make their way through it together."That's not to say Cristina and Owen, who rushed into marriage in the aftermath of the Seattle Grace shooting rampage, won't have a falling-out as a result of the abortion. "They were in an impossible position where he wanted one thing and she wanted another, and he gave her what he felt she needed," Rhimes says. "It's going to put them in a strange position with one another for a while."

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"They're going to shut down their feelings about it for quite some time," McKidd adds, noting that becoming chief is a blessing in disguise for Owen. "He has this very convenient environment where he can become so consumed with work that they can try and brush it all under the carpet. I'm not sure it's going to work. He genuinely tries to put that to bed and go, 'OK, this is the woman I love. This is the person I married.' But whether he can manage that in the long-term is going be the big question mark over Cristina and Owen." Though Meredith (Ellen Pompeo) was the one to persuade Owen to give Cristina his blessing, so to speak, McKidd believes that will come to a head in coming episodes. "Meredith supports her because it's her decision, in the same way that Owen supports her because it is her decision," he says. "I think Meredith is there for her, but what her true feelings are are going to come out later."

Grey's Anatomy airs Thursdays at 9/8c on ABC.