"I developed Hashimoto's Thyroiditis and adrenal fatigue and then spent the last five years managing my health so my body could cope with these toxic bags.
"Some women tolerate implants really well, but unfortunately I wasn't one of them."
Brunton-Rennie believed she was suffering from Breast Implant Illness (BII), which carries symptoms such as chronic fatigue, headaches, memory loss, ear ringing, muscle and joint pain, among other issues.
Despite thousands of women around the world suffering from BII, the illness is not recognised by the medical community.
Now 35-year-old Brunton-Rennie is eager to share her experiences with other women as a warning to the potential dangers and health risks involved with getting breast implants.
"It will be worth it to help the huge number of women out there who are unwell and have failed to realise that their implants may be a cause of their problems, and to try and inform other women who may be considering getting them so that they may make a more educated decision," she told Daily Mail Australia.
"When you first get them, no one ever considers the process of replacing them every 10 years or taking them out for good one day."
Since removing her breast implants, the Auckland PR executive can now breathe better but is still healing from the impact the implants had on her health.
Brunton-Rennie isn't the only New Zealand woman who has suffered ill-health following breast enhancement surgery.
Michaiah Simmons-Villari was stumped at why she felt so ill following surgery.
Post surgery the Event Co-ordinator began to suffer from glandular fever, chronic fatigue, shingles, seizures, depression, memory loss, auto immune disease and skin discolouration.
"I ended up in hospital a few times, hooked up to machines. I had memory blanks and I don't drink or do drugs. I work out, eat healthy, take supplements. There was no reason for it," she told Fairfax.
But it wasn't until she stumbled across Breast Implant Illness that she worked out what was wrong with her.
In 2016 she had them taken out and said she "felt so much better".
A year-and-a-half since she had them removed, Simmons-Vallari says she still believes her body is detoxing.
New Zealand Association of Plastic Surgeons president John Kenealy said there was no cause for concern, telling Fairfax there was "no scientific evidence that implants posed a health threat".
He said the symptoms the women had experienced were unable to be measured.
"At the end of the day, those things [fatigue, immune system problems, aches and pains] are very prevalent in the patient population anyway," said Kenealy.
