Convert mother's gestational weight gain (GWG) measurements to INTERGROWTH z-scores/centiles

iggwg_value2zscore(gagedays, val, bmi = NULL)

iggwg_value2centile(gagedays, val, bmi = NULL)

Arguments

gagedays: gestational age(s) in days at which gestational weight gain was measured (must be same length as val)
val: value(s) of the gestational weight gain (kg gained since pregnancy) measurement(s) to convert
bmi: optional value(s) of mother's pre-pregnancy BMI (kg / m^2) to check validity of GWG standard

References

Gestational weight gain standards based on women enrolled in the Fetal Growth Longitudinal Study of the INTERGROWTH-21st Project: a prospective longitudinal cohort study Ismail, Leila Cheikh et al. BMJ 2016;352:i555

Examples

# get z-score and centile for mother at 17 weeks with 2 kg gestational weight gain
iggwg_value2zscore(17 * 7, 2)
#> Argument 'bmi' not supplied... presuming valid pre-pregnancy BMI.
#> [1] 0.2619521
iggwg_value2centile(17 * 7, 2)
#> Argument 'bmi' not supplied... presuming valid pre-pregnancy BMI.
#> [1] 60.33208