Mortality rate of Japanese twins and triplets. III. Infant deaths of triplets after birth to one year of age.
The rate of infant mortality of triplet individuals (deaths under one year of age) was computed using 34 sets of triplets born in the first half of 1974. The rates were 8.82%, 9.68%, and 10.34% for the first-, second-, and the third-born triplets, respectively. For males and females the rates were 8.33% and 10.34%, respectively, and the difference was not significant. The rate decreased with gestational age up to 32-35 weeks. For those with heavier weight at birth (less than or equal to 2,000 g) the rate was lower (0%) than for those with lighter weight (less than 2,000 g, 8.16%), but the difference is not significant (P = 0.087). Infant mortality rate of triplets decreased with increased monthly expenditure of the household.
D001722:Birth Order; D001724:Birth Weight; D005260:Female; D005865:Gestational Age; D006801:Humans; D007182:Income; D007223:Infant; D007226:Infant Mortality; D007231:Infant, Newborn; D007564:Japan; D008297:Male; D011247:Pregnancy; D014310:Triplets