Brie Bella thought her twin sister Nikki Bella ''rushed'' into her romance with Artem Chigvintsev.

The 36-year-old retired wrestler has admitted she was initially concerned when her twin sister Nikki revealed she is expecting her first child with her fiancé Artem, because Brie believed things had moved too quickly for the couple.

In a sneak preview for the upcoming episode of 'Total Bellas', Nikki reveals her pregnancy news to her sister and confesses the baby wasn't planned, sparking Brie's concerns over the future of Nikki's romance with Artem.

Brie - who is also pregnant with her second child with husband Daniel Bryan, with whom she already has two-year-old daughter Birdie - said in a confessional: ''I'm very protective over my sister, and I don't want my sister to rush into everything,

''I feel like everything has been rushed with her lately. I don't want to take away from her having this child because it's such a beautiful thing, but when someone tells you that they feel like things have been moving too fast and less than 24 hours they tell you they are carrying that person's baby - how does one handle that?

''I just want to make sure she has a strong head on her shoulders because her whole life is about to change.''

Brie's concerns came after Nikki previously confessed she was ''freaking out'' over the 'Dancing with the Stars' alum's proposal, as part of her was concerned the next step in their relationship had come too soon.

And Nikki also confessed she wasn't ready to be a mother when she first discovered she was pregnant, because the news came just weeks after she had argued with Artem.

She said in an episode of 'Total Bellas' which aired last month: ''It's only been about a week since we got into our big argument, and honestly, this is just ... this is way too fast. I have so many things going for me. And right now, to think, getting pregnant, what it would do to my life, it would completely change it. For me, it is so important to make sure Artem and I have this amazing, solid relationship and that we are ready to be parents - if that day ever comes.''