"I've been doing acupuncture, which really helps with that [morning sickness], and Chinese herbs," the 37-year-old singer, born Stacy Ann Ferguson, said today on " Good Morning America."
"I'm just going to play it by ear and see how things go and let the natural instincts kick in," she added.
Fergie announced to the world via Twitter last month that she is expecting her first child with husband Josh Duhamel, 40.
"Josh & Me & BABY makes three!!! #mylovelybabybump," she tweeted Feb. 18, along with superimposed childhood photos of the couple.
The singer has stayed mostly mum since the announcement, while her husband, set to host the Kids' Choice Awards Saturday, let slip how his wife reacted to the positive pregnancy test.
"I know that my husband told everybody what I said, my quote when we found out, 'This [blank] just got real," she said. "It's true when that moment occurs to you that, yeah, there's going to be a human being growing inside of you. It's reality. It's amazing."
"We're thrilled and so excited," said Fergie, married to Duhamel since 2009.
While the singer has slowed the pace of her music career to focus on becoming a mom, she confirmed to "GMA" she is still writing music wherever, and whenever, she finds the inspiration.
"It always is so spastic, my writing," she said. "I could have one thought and it be so weird and have nothing to do with anything that's going on in my life."
She is also taking on a new adventure, teaming up with the makeup company Wet 'n' Wild, for which she serves as its global beauty ambassador, to develop the Perfect Pout V.I. Pink lip color.
A portion of the proceeds from each lipstick sold will be donated by the company to the American Foundation for AIDS Research (amfAR).
"We're so excited because it's a cause that's near and dear to me," Fergie said.