Feasibility study for the development of a sero-correlate of protection against invasive Group B Streptococcus disease (the iGBS study) - iGBS Feasibility

<b>Primary objective</b>To establish a control group of GBS colonised women for the main seroepidemiology studyTo test the feasibility of establishing national infant iGBS surveillance through our networks in preparation for the main seroepidemiology study<br><b>Secondary objectives</b>- To establish:the serotype-specific GBS anti-CPS IgG concentrations in cord blood in subjects colonised with GBS at deliverythe rate of serotype-specific GBS anti-CPS IgG concentrations decline during the at risk period of the first three months of lifean opt out approach to cord blood serum collection