Planning a wedding while pregnant has been a bit, well, bumpy for Audrina Patridge. “I definitely have baby brain,” confesses the Hills alum, 30, who is expecting her first child with fiancé Corey Bohan this summer. “I’m all over the place!”

Engaged in November, the couple of eight years announced her pregnancy in December. “There’s a lot going on — wedding planning, baby planning,” she tells Us Weekly. The pair have decided to tie the knot — possibly in a destination ceremony — after the baby’s arrival.

Now, says Patridge, it’s “crunch time” for selecting the dress for her end-of-the-year vows to the BMX dirt-biker, 34, especially since she’s entered her second trimester and is beginning to show. “I don’t want to have to worry about it after I have the baby,” she vows.

With her sister Casey Loza in tow, the Orange County, California–based mom-to-be tried on wedding dresses for Us cameras at a Pasadena mansion. Her dream dress: “casual-glam.” Says Patridge, “I like a little bit of pizzazz — I’m all about the details.”

Watch as Patridge swaths herself in yards of tulle, slips into a sexy mini and recalls Grace Kelly in classic lace — and see which dress made her sister tear up!

STYLING CREDITS:

Look 1: Theia Olivia strapless tulle ball gown ($1,595, theiacouture.com) and Kendra Scott Carey gold-plate and mother-of-pearl earrings ($85, kendrascott.com); Look 2: Calypso St. Barth’s Hanovi hand-embellished feather dress ($1,600, calypsostbarth.com); Look 3: Saja Wedding embellished lace tulle dress with long train ($2,800, sajawedding.com); Look 4: Theia Toni sequin slip gown ($1,495, theiacouture.com)

Can't get enough of Us? Sign up now for the Us Weekly newsletter packed with the latest celeb news, hot pics and more!