Hello. This is Dr Rubal Jain. Firstly you need to understand that the name “painless” is kind of a misnomer. As the painless vaccine is also an injectable vaccine and we cannot prevent the painful prick sensation. The difference between the painful and painless vaccines stand in their safety profile, where painless one causes lesser side effects such as pain at the site of injection, painful bump, fever, local swelling, inability to move the limb out of pain and swelling, vomiting, dullness, refusal to feed. Even if you had vaccinated your baby with a painless vaccination at 6 weeks, so long as you give the rest of her doses on proper time, any vaccine is good enough. Even if you now want to change it to painful one. Both the vaccines are equally effective and either can be given to your baby accordingly to your choosing.

Only 6 ,10, 14 wks and 18 months Vaccination cause fever if u choose painfull option for ur baby.     it doesn't cause fever as such due to vaccine component   In triple vaccine (DTwP,) wP component cause fever which is whole cell pertussis component   If u choose painless option for ur baby, It contain DTaP component ie acellular component(aP) which doesn't cause fever.  Both painless and painful Vaccines are equally good and effective.