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Birth Weight for Gestational Age

Canadian Perinatal Surveillance System

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Classification of growth for a particular gestational age is a critical part of fetal and infant care. References used at different centers are not always comparable, some are many years old and few have used rounding off to the nearest completed week of gestation as recommended by WHO. The Canadian Perinatal Surveillance System (CPSS) has developed this new population-based Canadian reference for birth weight for gestational age, which included data on all singleton infants born in Canada (with the exception of the province of Ontario) between 1994 and 1996 at 22 to 43 weeks gestation, comprising 347,570 males and 329,035 female infants. This reference was created during a period of increased availability of ultrasound confirmation of gestational age, and it is gender-specific.

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Birth Weight for Gestational Age (GA)

Birth Weight for Gestational Age, Male Singletons

Birth Weight (in g) for GA in Completed Weeks
Canadian Male Singletons
GA 3%ile 5%ile 10%ile 50%ile 90%ile 95%ile 97%ile Mean SD
Source of Information: Michael S. Kramer et al. A New and Improved Population-based Canadian Reference for Birth Weight for Gestational Age External Link. Pediatrics, electronic version, August, 2001. http://www.pediatrics.org/cgi/content/full/108/2/e35
22 338 368 401 490 587 627 659 501 111
23 406 434 475 589 714 762 797 598 114
24 468 498 547 690 844 902 940 697 125
25 521 557 617 795 981 1,048 1,092 800 147
26 571 614 686 908 1,125 1,200 1,251 909 178
27 627 677 763 1,033 1,278 1,358 1,416 1,026 209
28 694 752 853 1,173 1,445 1,532 1,598 1,159 241
29 780 845 964 1,332 1,629 1,729 1,809 1,312 273
30 885 959 1,099 1,507 1,837 1,955 2,053 1,487 306
31 1,012 1,098 1,259 1,698 2,069 2,209 2,327 1,682 339
32 1,164 1,266 1,444 1,906 2,319 2,478 2,614 1,896 369
33 1,344 1,460 1,648 2,127 2,580 2,750 2,897 2,123 391
34 1,552 1,677 1,866 2,360 2,851 3,029 3,184 2,361 410
35 1,783 1,907 2,091 2,600 3,132 3,318 3,475 2,607 428
36 2,024 2,144 2,321 2,845 3,411 3,604 3,759 2,855 443
37 2,270 2,384 2,552 3,080 3,665 3,857 4,003 3,091 449
38 2,498 2,605 2,766 3,290 3,877 4,065 4,202 3,306 448
39 2,684 2,786 2,942 3,465 4,049 4,232 4,361 3,489 445
40 2,829 2,927 3,079 3,613 4,200 4,382 4,501 3,638 447
41 2,926 3,025 3,179 3,733 4,328 4,512 4,631 3,745 459
42 2,960 3,070 3,233 3,815 4,433 4,631 4,773 3,800 485
43 2,954 3,081 3,249 3,864 4,528 4,747 4,941 3,793 527

Birth Weight for Gestational Age (GA)

Birth Weight for Gestational Age, Female Singletons

Birth Weight (in g) for GA in Completed Weeks
Canadian Female Singletons
GA 3%ile 5%ile 10%ile 50%ile 90%ile 95%ile 97%ile Mean SD
Source of Information: Michael S. Kramer et al. A New and Improved Population-based Canadian Reference for Birth Weight for Gestational Age.External Link Pediatrics, electronic version, August, 2001. http://www.pediatrics.org/cgi/content/full/108/2/e35
22 332 347 385 466 552 576 576 472 72
23 379 403 450 557 669 706 726 564 95
24 424 456 513 651 790 839 887 656 121
25 469 508 578 751 918 982 1,060 754 152
26 516 562 645 858 1,060 1,139 1,247 860 186
27 569 624 717 976 1,218 1,313 1,446 976 222
28 634 697 802 1,109 1,390 1,499 1,657 1,107 254
29 716 787 903 1,259 1,578 1,701 1,885 1,256 286
30 814 894 1,022 1,427 1,783 1,918 2,121 1,422 319
31 938 1,026 1,168 1,613 2,004 2,150 2,347 1,604 345
32 1,089 1,184 1,346 1,817 2,242 2,399 2,578 1,808 368
33 1,264 1,369 1,548 2,035 2,494 2,664 2,825 2,029 389
34 1,467 1,581 1,768 2,266 2,761 2,948 3,097 2,266 409
35 1,695 1,813 1,998 2,506 3,037 3,242 3,384 2,512 426
36 1,935 2,052 2,227 2,744 3,307 3,523 3,660 2,754 439
37 2,177 2,286 2,452 2,968 3,543 3,752 3,886 2,981 443
38 2,406 2,502 2,658 3,169 3,738 3,931 4,061 3,181 439
39 2,589 2,680 2,825 3,334 3,895 4,076 4,202 3,350 434
40 2,722 2,814 2,955 3,470 4,034 4,212 4,331 3,486 434
41 2,809 2,906 3,051 3,576 4,154 4,330 4,444 3,588 439
42 2,849 2,954 3,114 3,655 4,251 4,423 4,554 3,656 448
43 2,862 2,975 3,159 3,717 4,333 4,495 4,685 3,693 459

Birth Weight for Gestational Age - Poster

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Birth Weight for Gestational Age - Poster