The Ministry of Health recommends that all women who have ever been sexually active should have regular cervical smear tests from the time they turn 20 until they turn 70
When Miss Sarjantson was finally given a smear test, it was too late as she had already been diagnosed with aggressive cancer that had taken over her body.
After a hysterotomy last summer and four weeks of radiotherapy, doctors thought she was in the clear.
But in April, she was told the cancer had returned and by that point her body was too weak to undergo chemotherapy treatment.
She was transferred to hospital on June 30 and remained there until her death on August 12.
Miss Sarjantson, from Blackpool, had been due to marry her fiancé Karl Hyde in March until her illness forced them to cancel.
The mother-of-one, an early years practitioner, was so devoted to her 20-month-old son Ronnie she even timed her radiotherapy treatment on the morning of his first birthday so he could still have a party in the evening.
Her mother, Lisa, said: "She was a loving person and very close with her little boy. Throughout the whole thing, she remained positive.
"She never gave in and made a bucket list because as far as she was concerned she was going to beat it."
She added: "She was trying to plan camping trips. She really wanted to get better and to carry on - as far as she was concerned that's what she was going to do.
"Even when the doctors said you don't have to have any more operations if you don't want, she said 'no, that would be giving in'".
Mr Hyde, a corporal in the army, has now transferred to the second battalion, Duke of Lancaster's regiment, based at Weeton, so he can be at home to look after their son.
Her family are now campaigning to lower the age limit for cervical screening and said a simple procedure could have prevented the tumour developing.
Her sister, Zoe, 28, who worked with Rachel, said: "If the age limit had been lowered already, she might still be here.
"So many young girls are dying of it. Maybe in time they can help other mums, for their children's sake if not anything else."
About 3,000 cases of cervical cancer are diagnosed each year in the UK, which amounts to 2 per cent of all cancers diagnosed in women.
Cervical cancer often has no symptoms in its early stages but the most common is irregular bleeding, in between periods, after sex or after the menopause.
- Daily Mail