HSE officials have been defending the rolling out of the HPV vaccination, after comments made by a bishop this week in which he claimed it could make young girls engage in more risky sexual behaviour.
Bishop of Waterford and Lismore Phonsie Cullinan said giving the injection to 12-year-old girls to guard against the human papilloma virus could lead to promiscuity.
"It's not only a medical issue, it's a lifestyle issue," he said. "It affects the lifestyle of our young people."
The Bishop added: "We have to do better than to give our boys condoms and our girls injections at the age of 12."
Head of the HSE National Immunisation Office, Dr Brenda Corcoran said it was important that parents listened to experts on the subject.
"We would ask parents to think about where they get their information from. All the information from the HSE is endorsed by national or international regulatory or expert bodies, including the World Health Organisation.
"Some of the information that came out during the week was not factually correct. The vaccine is 99.9999% safe."
Since 2010 more than 230,000 girls have been vaccinated, with about 1,000 reporting adverse reactions.
Most commonly, people fainted when injected or showed gastrointestinal symptoms, malaise, headache, dizziness and injection site reactions.
Other allergic-type reactions have been reported, including skin rashes, hives and flushing and isolated reports of more severe hypersensitivity-type reactions and some reports of persisting or chronic fatigue.
Ireland has one of the highest cervical cancer rates in Europe with more than 90 women dying from the disease every year and more than 280 others needing surgery, chemotherapy and/or radiotherapy.