Tristan Thompson and Khloe Kardashian are expecting their first child. Picture: Instagram

Khloe Kardashian was "nervous" about posting her pregnancy news online, but has been "overwhelmed" by the support she has received.

The 33-year-old reality star took to Instagram on Wednesday to confirm she is expecting her first child with her NBA star beau Tristan Thompson, and has now admitted the pressure of putting out such an important announcement was more than a little scary.

In a tweet posted shortly after her Instagram post - which featured her baby bump with her and Tristan's hands covering it - was uploaded, she said: "I was so nervous to post our announcement but WOWWW I am overwhelmed with the response by you guys!!! Thank you! Thank you! I love you guys!! (sic)"

A second tweet shared around the same time simply featured five love heart emojis.

As of the time of writing, none of Khloe's famous family and 'Keeping Up with the Kardashians' cast mates have shared their thoughts on her decision to finally go public with the news, after months of speculation from various sources and news outlets.