The province has the highest rate of the infection among newborn babies among Wales, England and Northern Ireland.
Figures from the Health Protection Agency published in November show the rate of GBS infections in the first 90 days is 0.77 per 1000 live births, compared with 0.68 per 1000 in England and 0.61 for all three countries combined.
Susan Kyle, supporter of charity Group B Strep Support, said at an information event in the Long Gallery, Stormont: ‘Every mother should have the right to protect her baby from this deadly, but preventable, infection.
'In many countries – Canada, France, Italy, Australia and the USA to name a few, testing for GBS is a routine part of antenatal care. Northern Ireland cannot ignore its high infection rate.’
GBS infections can be life threatening, leading to blood poisoning and meningitis. Screening could prevent up to 80% of infections and tests cost around £32 each, the charity said.