The influencer, who announced her pregnancy with fellow MAFS star Michael Brunelli earlier this month, explained to followers she had been suffering from hyperemesis gravidarum.
The condition has been causing severe nausea and vomiting, with the star admitting she had lost 10kgs as a result and had not gotten out of bed for two months.
Martha has now shared a picture on her Instagram Stories showing her frail frame at 16 weeks pregnant following the weight loss.
In an Instagram Q&A, Martha said she had tried "literally everything" to curb her pregnancy sickness.
"I've taken all the drugs, but there is no relief from the nausea ... ever!" she wrote over a photo of her ugg boots.
"I was recently prescribed steroids which have helped. My obstetrician said, 'They won't make you feel normal but they will help you to feel human again', which I can confirm.
"I've had so many questions about which meds I'm on and I don't really know if sharing this kind of thing is right but I also want to be able to help anyone else who might be suffering the same thing."
Martha told her followers Michael had been a "saint" and not left her side as she struggled through the first trimester.
"If I throw up, he's there, telling me it's OK. If I wake up, he wakes up. He brings me food at 4am when the nausea wakes me. He gives me all my meds," she said.
"I never would have been able to do this without him."
Despite Michael tending to Martha's needs, she also said she had "never been more irritated by him".
"He can't do anything right in my eyes ... I don't know why but I'm just so annoyed by everything he does and all he does is help," she said.
Their baby news comes after the pair got engaged last year.
The pair took to their Instagram accounts to upload an adorable selfie, with the caption simply saying: “Mrs B”.
The photo showed Martha’s eye-popping diamond engagement ring from Armans Jewellery, which consisted of a single, stunning, emerald-cut diamond.
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