Can women who are found to be carrying Group B Strep (GBS) still have a waterbirth (in a hospital birth pool or at a home water birth)? Yes!
GBS is very common. It’s thought that around 1 in 4 women carry the bacteria in their vagina, but despite this very few babies become affected by it. However those who are affected can become extremely ill, and tragically some will die. Because of this, prophylactic antibiotics given during labour are offered to women who are found to be carrying GBS, which does reduce the number of affected babies.
Our binary maternity labelling (low/high risk) means that any woman with any additional issue in their pregnancy becomes “high risk”, and many trusts’ guidance on waterbirth states that only “low risk” women may use the birth pool. In many cases this leads to women who would hugely benefit from a birth pool, and who would be far more likely to have a straightforward, drug-free birth by using one, being denied access to them.
Is this reasonable, or should women be supported to have a waterbirth if they wish, if they’re a GBS carrier?
What is the evidence?
Cohain1 states that out of 4432 waterbirths, only one incident of GBS was reported, whereas the rate for dry land births was one in 1450. This implies that waterbirth may significantly lower the rates of GBS infection in babies who are born in a birth pool. Research by Zanetti-Dällenbach R2 et al found that even though the levels of GBS in the birth pool were higher when babies were born into the water compared to labouring in water and birthing on land, the levels of GBS infection in the babies born in water was lower. While no large scale RCTs have yet been done, this data does show that birthing in water may in fact be a hugely important way to reduce the numbers of babies who are contracting GBS after birth and perhaps we should be encouraging women to birth in water as a way to reduce the infection rate! Even the Royal College of Obstetrics and Gynaecology (RCOG) states that waterbirth is not contraindicated for women who are carrying GBS3.
Women who are found to be carrying GBS before labour are offered prophylactic antibiotics which, if she chooses to accept them, will be given via a cannula during birth. This is often considered to be a contraindication for labouring and birthing in water, but in fact it is very simply to protect the cannula during a waterbirth. Women can either keep their hand out of the water, or if they feel they might want to put their hand into the birth pool, the midwife can place a close fitting plastic glove over her hand and seal it with an appropriate skin-safe waterproof tape.
In conclusion, the evidence we have – limited as it is – shows that giving birth in water is actually protective against the baby contracting GBS, and as such we shouldn’t be asking whether women should be supported to birth in water if they are carrying GBS. Instead we should be asking why are they so often told that they must birth on dry land?
AIMS: Group B Strep Explained by Sara Wickham https://www.aims.org.uk/shop/item/group-b-strep-explained
1) Cohain, JS, Midwifery Today, “Waterbirth and GBS”: https://www.ncbi.nlm.nih.gov/pubmed/21322437
2) Zanetti-Dällenbach R, “Water birth: is the water an additional reservoir for group B streptococcus?“ https://www.ncbi.nlm.nih.gov/pubmed/16208480
3) RCOG on GBS and waterbirth: https://obgyn.onlinelibrary.wiley.com/doi/full/10.1111/1471-0528.14821 (point 7.5)
Topic Summary: Hospital birth pools and GBS: what is the evidence and what is best practise?