“…The definition of stillbirth varied between the studies (16, 20, 22 and 28 weeks of gestations), and this information was also missing from some studies. In total, 18 studies reported mortality for singletons only (5, 8, 10–13, 18, 19, 20/23, 25, 26, 28, 29, 33, 34, 39, 43, 44), 11 included both singletons and multiple births (2, 9), (14), (21), (24), (34), (36), (38), (40–42), one study included non‐malformed singletons only (44), and one had separate analyses for all newborns and singletons (17). For the remaining studies, it remained unclear whether all newborns were included or singletons only.…”