[1] Univ Coll Cork, Dept Obstet & Gynaecol, Pregnancy Loss Res Grp, Cork, Ireland
[2] Univ Coll Cork, Natl Perinatal Epidemiol Ctr, Cork, Ireland
[3] Univ Coll Cork, Pregnancy Loss Res Grp, Cork, Ireland
[4] Natl Univ Ireland, Sch Nursing & Midwifery, Galway, Ireland