### Description

Maternal weight increases during normal pregnancy. Insufficient or excessive weight gain may pose or indicate problems for both mother and fetus.

The following table was extracted from a graph of acceptable limits for weight gain for week of pregnancy (Wolfe, 1993).

week of pregnancy

lower limit for weight gain in pounds

upper limit for weight gain in pounds

8

0.25

2.25

10

0.75

3

12

2

4

14

3.5

5.5

16

5.5

8.5

18

8

11.5

20

10.5

14.5

22

12.5

17.5

24

14.5

20.25

26

16.5

23

28

18.25

25

30

20

27

32

21.5

29

34

23

30.25

36

23.5

31.5

38

24

32

40

24

32.5

weight gain during pregnancy in pounds =

= (current body weight in pounds) - (usual body weight before pregnancy)

Lines Approximating Limits for Desirable Weight Gain (from JMP)

Lower Limit for Desirable Weight Gain

8 - 40 weeks (as a single equation)

= (0.0000276 * ((weeks)^4)) - (0.003918 * ((weeks)^3)) + (0.170149 * ((weeks)^2)) - (1.848556 * ((weeks))) + 5.9252302

?

8 - 16 weeks (1st of 3 segments)

= (-0.002604 * ((weeks)^3)) + (0.1517857 * ((weeks)^2)) - (1.81994 * ((weeks))) + 6.4178571

16 - 32 weeks (2nd of 3 segments)

= (0.000342 * ((weeks)^3)) - (0.041126 * ((weeks)^2)) + (2.3628096 * ((weeks))) - 23.16739

32 - 40 weeks (3rd of 3 segments)

= (0.0052083 * ((weeks)^3)) - (0.616071 * ((weeks)^2)) + (24.33631 * ((weeks))) - 297.05

Upper Limit for Desirable Weight Gain

8 - 40 weeks (as a single equation)

= (0.0000663 * ((weeks)^4)) - (0.00809 * ((weeks)^3)) + (0.3256687 * ((weeks)^2)) - (3.931889 * ((weeks))) + 16.852008

8 to 16 weeks (1st of 3 segments)

= (0.0130208 * ((weeks)^3)) - (0.379464 * ((weeks)^2)) + (4.0550595 * ((weeks))) - 12.58214

16 to 32 weeks (2nd of 3 segments)

= (-0.000789 * ((weeks)^3)) + (0.0324675 * ((weeks)^2)) + (1.1341089 * ((weeks))) - 14.77814

32 to 40 weeks (3rd of 3 segments)

= (- 4.9 * (10^(-16)) * ((weeks)^3)) - (0.040179 * ((weeks)^2)) + (3.3303571 * ((weeks))) - 36.45