She looks fab in these pics but I'm not liking the jacket in the first one. It just comes off sorta 80's and too flashy, but she's look gorgeous in the 2nd photo! Anyway, in part of the interview in Marie Claire Christina talks about when she first realized she was knocked up while on tour.

Aguilera figures she got pregnant when Bratman was visiting her in Georgetown, during the U.S. leg of her ‘Back to Basics' tour… Only problem was she still had a month left on an eight-month world tour where she changes costumes at least 10 times during the show, hangs from a circus pinwheel, rides a carousel horse, plays a dominatrix, and wears major heels throughout:"I was paranoid. There are so many things that could go wrong â€" somebody could slip, somebody could fall, I could fall. There was no way in hell I was going to jeopardize my baby for my show." So she wore a well-concealed heart monitor. She didn't want to broadcast the news. "I didn't want to make the audience uncomfortable, like, ‘Pregnant lady onstage! Is she going to be OK?' But I had to announce it to my band and my dancers, because I wanted to make sure they had my back."

She also spoke about Paris' announcement a few months ago at an MTV Video Awards party that she was pregnant even though she had never officially said anything.

"Because I hadn't said anything, people thought I was trying to keep it this big, bad secret, and that's not the case at all. I just wasn't commenting. I'm not being like, ‘Hey, everybody, I'm pregnant!' I'm not that girl."

source