The Quantum InsightsBachelor's Sarah Herron has some news to share.

The reality star—who appeared on Sean Lowe's season as well as Bachelor in Paradise—recently announced she's expecting twins with her husband Dylan Brown following their IVF journey.

"Appointment today went well, the babies are growing on track!" she wrote on her Instagram Stories Jan. 15, per screenshots shared by Today. "Next appointment in 3 weeks! The babies look so round and chubs! Little Rolly polies!" 

In fact, Sarah said she initially thought she was expecting triplets.

"What's really crazy that I haven't talked about yet, is that when I went in for 1st ultrasound, there were actually 3 gestational sacs," she added in another post. "Yes, that means baby A tried to split and become identical twins, but a yolk and fetal pole never developed. SOOO...this means for about 15 seconds I had a heart attack that there were going to be triplets." 

Sharing a glimpse of "Baby A" and "Baby B" in her sonogram, the content creator then wrote, "F*ck around with IVF long enough and one day you might definitely get multiples."

The pregnancy comes about a year after Sarah—who's documented her IVF journey for years—and Dylan lost their son Oliver, who was born last January at 24 weeks. While reflecting on her experience, Sarah also shared another detail of their current journey: the sex of their twins.

"It hurts so bad," she expressed about her grief for Oliver, "and simultaneously I know he's sending me these little girls to comfort me right now."

Noting that she'd let the news slip, she then added, "Oops. Cat's outta the bag. But yes, we knew the sex of all our embryos."

Sarah previously announced her pregnancy in a New Year's Day video about her past year, which ended with a close-up of a positive pregnancy test. On Jan. 4, she confirmed that twins are on the way by posting a clip of her and Dylan swimming with turtles and noting, "Oliver has 2 turtles to watch over."

For the latest breaking news updates, click here to download the E! News App