(Photo Credit: kimzolciakbiermann/Instagram)

"Real Housewives of Atlanta" star Kim Zolciak has never been one to shy away from the camera and the fact that she is expecting twins hasn't changed her one bit.

The mother of four, 35, posted an Instagram selfie this past weekend, showing off her rapidly growing baby bump, covered only by a strapless black and white bikini.

"Going swimming with the kiddos! The pool makes me feel so much lighter! This belly #twins #excited #blessed #nofilter," the caption read.

Read: Kim Zolciak Is Expecting Twins

Zolciak announced last month that she and her husband, Atlanta Falcons player Kroy Biermann, 28, were adding two more their clan, making six total.

"I'm having twins and I couldn't be more excited. I was completely shocked. I had no idea," she told E! News. "It was a natural conception, but twins do run in the family, so I guess I shouldn't have been surprised."

This isn't the first time Zolciak has taken to Instagram to show her growing bump. At the end of July, she posted a gym pic in a black pulled-up top and sweats with the caption, "You asked for it … here is my baby bump this morning!!"

The twins will join Brielle, 16, Ariana, 11, Kroy Jr., 2, and Kash, 1.