Table 4.

Distributions of Birth Weights by Gestation, Sex, and Plurality

(n)Birth Weight (Grams) n (%)
<500 Grams
MedianIQRMinimum to Maximum
All infants21 wk (3)440440–5082 (66.7%)
22 wk (22)540467–604364–7406 (27.3%)
23 wk (131)600560–665390–98010 (7.6%)
24 wk (298)680620–759460–9647 (2.4%)
25 wk (357)760680–848370–10408 (2.2%)
Total (811)695610–786360–104033 (4.1%)
Gestational age
22 wk (n = 22)Boys (10)540515–590364–680
Girls (12)540456–618410–740
Singletons (13)555520–640445–680
Multiples (9)467423–590364–740
23 wk (n = 131)Boys (70)615570–690400–980
Girls (61)600550–650360–850
Singletons (96)621578–683400–980
Multiples (35)575530–630360–772
24 wk (n = 298)Boys (166)700640–785470–950
Girls (132)660593–711460–964
Singletons (213)680622–770470–964
Multiples (85)670610–730460–907
25 wk (n = 357)Boys (187)780685–875370–1040
Girls (170)739670–810470–1000
Singletons (249)770690–858470–1040
Multiples (108)737646–832370–994
Total (n = 811)Boys (436)712632–822364–104012 (2.8%)
Girls (375)680600–758360–100021 (5.6%)
Singletons (574)700622–796400–104016 (2.8%)
Multiples (237)670600–760360–99417 (7.2%)