Table 1

Causes of death among live births whose co-twin was a fetal or infant death

Gestational age (weeks)	BW of fetal death* (g)	Registered cause of fetal death*	BW of live birth (g)	Cause of death in liveborn twin	Age at death	Sex of the pair/chorionicity
*Refers to infant death in infant death plus infant survivor group.
BW, Birth weight; TTT, twin-twin transfusion; TRAP, twin reversed arterial perfusion; MM, male-male; FF, female-female, ULS, unlike sex; MC, monochorionic; DC, dichorionic; HMD, hyaline membrane disease; IVH, intraventricular haemorrhage; IUGR, intrauterine growth retardation.
Causes of death in the liveborn twin of a co-twin fetal death
28	595	TTT syndrome	1235	TTT syndrome; pulmonary immaturity; IVH	7 days	MM/MC
29	1600	TTT syndrome	1140	TTT syndrome	18 days	MM/MC
29	Unknown	Fetus papyraceous	1500, male	Renal agenesis	1 hour	unknown
30	990	TTT syndrome	1179	TTT syndrome; extensive white matter infarction	32 days	FF/MC
31	2795	Acardia; anencephaly; multiple anomalies	1470	TRAP sequence	1 day	MM/MC
32	1475	TTT syndrome	1635	TTT syndrome	14 days	MM/MC
34	2620	TTT syndrome	1670	TTT syndrome	14 hours	FF/MC
36	477	Acardia; anencephaly	2000	Congenital cardiac anomaly	40 days	FF/MC
38	Unknown	Fetus papyraceous	2190	TTT syndrome; microcephaly; cerebral palsy	102 days	FF/MC
39	1280	IUGR, macerated fetus	1180	Respiratory obstruction; epileptic fit; cerebral palsy	11 years	FF/unknown
40	2780	Antepartum anoxia	4000	Intrapartum anoxia	7 days	MM/MC
40	2360	Antepartum anoxia	3360	Intrapartum anoxia	5 minutes	ULS/DC

Causes of death in childhood in infant survivors whose co-twin was an infant death
26	790	HMD, IVH	690	Cardiac arrest; bronchopneumonia; bronchopulmonary dysplasia	13 months	FF/unknown
38	2090	Coarctation of aorta	2295	Respiratory arrest; sleep apnoea; cerebral palsy	7 years	MM/unknown
36	2010	Miscellaneous (inborn error)	2110	Niemann-Pick disease	13 years	MM/unknown