Mum Kate told A Current Affair her daughter Marleigh relies on blood donations because of an incurable condition that is potentially fatal and has no cure.
Kate fought for years to have the rules changed in Australia that would allow more people to donate lifesaving plasma.
Kate said Marleigh suffered seizures that lasted up to almost 40 hours and their gay male friends were heartbroken they could not donate blood when the young girl was at her sickest.
鈥淗er immune system is wrongly identifying her healthy brain cells as foreign and attacking her brain,鈥 she said.
鈥淲e have so many friends, particularly our gay male friends, who would love to donate for Marleigh.
鈥淎ll they wanted to do was go and jump in a seat at Lifeblood and donate the blood.鈥
According to Lifeblood, earlier rules prevented gay and bisexual men and transgender women from donating blood or plasma if they had sex with men in the past three months.
Lifeblood will remove most sexual activity wait times for plasma donations from July 14, which means most people, and anyone who takes pre-exposure prophylaxis that meets other eligibility criteria, will be able to donate plasma.
The lifesaving organisation expects an extra 24,000 Australians will be able to give about 95,000 donations of plasma each year.
Lifeblood chief medical officer Jo Pink said with plasma now the donation type most needed by Australian patients, the change came at an important time.
鈥淲e鈥檙e excited to be able to welcome more people from across the community into our donor centres from next month,鈥 she said.
Dr Pink said the Therapeutic Goods Administration was also in the process of approving their submission to remove gender-based sexual activity rules, which means all donors will be asked the same rules about their sexual activity.
She said their submission to change rules for blood donation included data that showed a six month wait was the safest option for Australian patients.
鈥淏ut we are committed to reviewing this as more evidence becomes available,鈥 she said.
鈥淭here are many steps that Lifeblood needs to take before we can implement the new gender-neutral assessments, including working with state and territory governments to change the donor questionnaire.
鈥淲e hope to be able to implement this part of the changes next year.
鈥淏lood safety is and always will be our top priority but we know the current donation rules have been very difficult for many people in the LGBTQIA+ community.
鈥淲hile they were put in place to ensure a safe blood supply in the past, we know that they鈥檝e contributed to the stigma faced by the community.鈥
Health Equity Matters chief executive officer Dash Heath-Paynter said he welcomed this change that could unlock thousands of donations of lifesaving plasma.
鈥淲hile there is still more work, the Therapeutic Goods Administration鈥檚 approval for gender neutral assessments for blood donation is welcomed,鈥 he said.
鈥淚n terms of plasma donations, these changes mean Australia鈥檚 regulations are world-leading.鈥
Kirby Institute head of global health program John Kaldor said Lifeblood had developed pragmatic and innovative new procedures for blood donations with scientific evidence that shifted societal expectations.