A pregnant woman in Australia experienced a strange symptom that led to a shocking breast cancer diagnosis. Her colostrum was reddish-pink in color instead of yellow.

Kate Grainger, 31, noticed the discoloration in her breast milk when she was just weeks away from giving birth in February. She initially brushed it off as a random pregnancy side effect, reported 7 News.

"I didn't think anything of it. I was like, 'Oh pregnancy boobs, weird things happen,'" Grainger told the outlet.

Her baby was born in March. Grainger, a teacher, also has three other children with her husband Joel, 35.

The couple, from Newman in Pilbara, then traveled to Busselton in Western Australia, where her in-laws lived as their town had no birthing facilities. Grainger checked with a lactation consultant about the discoloration.

She was advised to undergo an ultrasound of her breasts and the results showed something she least expected. Grainger was found to have a mass the size of a walnut inside her breast.

"Nothing they could say would reassure me that it was okay," she said, recalling the tough times.

Doctors found a swollen lymph node, as well as dilated ducts in both breasts. A number of biopsies and scans followed to determine whether the lump was cancer.

"I worried myself so much that I'd actually gone into the hospital and asked them to sedate me because I was so upset," she said. "My husband and I were trying to cling to the positives."

Her fears turned into reality. At 37 weeks pregnant, Grainger learned she had rare Grade 3 triple negative breast cancer — a type that has a higher spreading rate than other kinds and with fewer treatment options.

"When she told us it was cancer, it just felt like a terrible episode of 'Grey's Anatomy' because it's just so rare to have breast cancer in pregnancy," Grainger said.

After further tests, she was advised to undergo chemotherapy as other forms of treatment wouldn't work. "It's the rarest type of breast cancer and hardest to treat," Grainger told 7 News.

Grainger appeared for the first of what could be up to 20 chemotherapy sessions just nine days after her son's birth. She will now have to undergo surgery – which may include a double mastectomy – radiation and possibly further chemotherapy.

Grainger believes the treatment will take about a year to complete. The mom of three is now cautioning other women to check for signs of any abnormalities.

"Check your boobs," she warned.

"What is meant to be a peaceful time preparing for the upcoming birth, has suddenly changed," she reportedly wrote on social media. "We are meeting with the specialist team ... to learn more and come up with a plan to get bub here safely and to find out the full extent as to what is happening right now."

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The "Big C" shouldn't be a cause for shame. PDPics - Pixabay