The Keeping Up With The Kardashians star, who is reportedly due in December, slipped into a thigh-split black maxi dress, which she teamed with high heels.
In a picture posted to Instagram, Kourtney can be seen talking to Kim, who's famous derrière is shown from a side angle, while Khloe places her hand on Kourtney's arm.
Looking as glamorous as ever, Kourtney protectively put her hand over her blooming baby bump.
Reality star Kourtney, 35, announced she was pregnant with her third child in June.
Viewers watched her tell long-term partner Scott Disick that they were expecting a third child in a teaser preview of the new series of KUWTK.
This will be Kourtney and Scott's third child. The couple are already proud parents to four-year-old son mason and two-year-old daughter Penelope.
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More stars who have announced baby news this year:
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