copied this from Lisa Barrett's website- she's a independant midwife (hope she doesn't mind) I didn't copy and paste it all cos it was long but you can google the rest if you like

This week I have been in contact with the hospital system and had extensive discussions about GBS. Group B Strep is a bacteria that can live in your vagina. It is transient - it comes and goes- 15 to 30% of us have it at one time. This is only a potential problem if you happen to be pregnant.

Strep B also known as GBS

There is a lot of scare mongering about GBS and it's implications, so what is the real deal?

Well first of all should you get the test? In the UK where screening isn't part of the antenatal testing circus this is what they have to say:
Estimated effects of bacteriological screening. Approximately 25% of mothers in the UK are likely to be GBS carriers. This estimate is based on a single study performed in the 1980s and it is possible that this study does not reflect the current picture. With the addition of women who present with other clinical risk factors for GBS disease, such as preterm labour, around 30% of all pregnant women would receive intrapartum antibiotic prophylaxis if a bacteriological screening programme were to be introduced in the UK (this is approximately 204,000 women per annum).

n Australia GBS testing is routine at about 36 weeks. If this is positive, you are assumed to be positive at the time of birth. The standard hospital treatment for this is antibiotics when in labour. Just because you have gbs in your vagina doesn't mean you have an infection it means you have the risk of an infection. Just because you had gbs at 36 weeks doesn't mean you have it at term as it grows in cycles.

Antibotics are promoted as a preventative measure, which isn't true. Antibiotics are not there to prevent infection but to cure it. As shown in the studies here, most people with gbs will give birth and their baby will either not be colonised by gbs or the baby will be colonised but suffer no ill effects. Antibiotics are inconsequential to those people, but there is a minute part of the population who's baby will be colonised and become extremely ill from gbs. The Medical fraternity feel that antibiotics will cure any disease and have insignificant effects to those who have taken it unnecessarily.

The cochrane data base also says that although antibiotics reduces the rate of infection it hasn't been shown to alter the the rate of death.
This is how most of the medical interventions occur, better to do something rather than just wait.

Antibiotics - When in doubt, give them out!

aking unncessary antibiotics also carries a risk.

?1 in 10 chance of an allergic reaction.
?1 in 10,000 chance of a severe allergic reaction like anaphylaxis.
?1 in 100,000 chance of death from taking antibiotics.

There is also a chance that the antibiotics affect the baby by restricting growth of natural flora which affects immune development.

Remember , this may all be worth it if you have an infection but having a positive swab doesn't mean you have the infection but the risk of infection as listed below.