A difficult labour can also increase the risk of streptococcal infection. The mechanism seems straightforward. If there are group B streptococci in the mothers vagina, the numbers reaching the baby will be greater if labour is prolonged, or if instruments are used. Once the membranes surrounding the baby in the womb, the 'waters' are broken, there is a direct open passage for bacteria between the baby and the vagina. So prevention of disease must include hygiene and good obstetric practice.
Prematurity is also a risk factor.
More survivors could mean more chances of group B streptococci to cause illness, which could explain the increased incidence of the disease in modern times. In Conclusion Group B streptococci have given the medical profession a new challenge in the last 30 years. Effective methods of prevention are still being sought, and vaccination is one possibility for the future. However, good hygiene and obstetrics remain as important as ever.