Table 2.

Overview of published cohorts reporting outcomes in conservatively treated fetuses with a first-trimester longitudinal bladder diameter > 15 mm

Reference	Cases	Cohort characteristics	Time period	Cases with 1 st trimester megacystis > 15 mm	Prenatal death	Liveborns	Neonatal survivors	Isolated 1 st trimester megacystis > 15 mm and favourable outcome?
[31]	43	Retrospective single center	2009–2020	14	12	2	2	Not available
[27]	27	Retrospective single center	2015–2023	2	2	0	0	None
[25]	145	Retrospective single center	1992–2002	31	31	0	0	None
[94]	23	Retrospective single center	2011–2016	11	11	0	0	None
[29]	5	Retrospective multi-center	2007–2015	2	0	2	2	None
[95]	98	Retrospective single center	2010–2020	22	20	2	Not available	Not available
[96]	1 (others with VAS)	Retrospective single center	2008–2012	1	0	1	0	None
[28]	2 (others with VAS)	Retrospective single center	2008–2012	2	1	1	1	1
[97]	46	Retrospective study	2003–2008	9	8	1	1	None
Total	390	Not applicable	1992–2023	94	85	9	6	1

This table summarizes retrospective studies assessing fetuses with an LBD > 15 mm diagnosed during the first trimester of gestation, who were not treated with vesico-amniotic shunting. Reported outcomes include prenatal death, live birth, and neonatal survival. The final column indicates whether any evidence of isolated first-trimester megacystis with LBD > 15 mm and a favorable outcome (i.e., survival without severe postnatal morbidity) was identified in the respective cohort. The data illustrate that spontaneous resolution and favorable postnatal outcomes in fetuses with isolated megacystis and a first-trimester LBD > 15 mm are exceedingly rare

LBD Longitudinal bladder diameter, VAS vesico-amniotic shunting