Offering fragile X syndrome carrier screening: A prospective mixed-methods observational study comparing carrier screening of pregnant and non-pregnant women in the general population M. Martyn, V. Anderson, A. Archibald, R. Carter, J. Cohen, M. Delatycki, S. Donath, J. Emery, J. Halliday, M. Hill, L. Sheffield, H. Slater, F. Tassone, S. Younie, S. Metcalfe 2013 / Vol. 3 / Bmj open