Table 2.

Parameter distributions used in Monte Carlo simulation for HCB in humans

Model parameter (units)	Distribution	Mean parameter value	Standard deviation	Range	Reference
Maternal age at delivery (years)*	Normal	25	6	15 - 54	Martin et al. (2012)
Pre-pregnancy weight (kg)	Normal	74.7	17.8†	50 – 114	McDowell et al. (2008)
Gestational weight gain (kg)	Normal	14.3	5.1	0 - 45.4	Oken et al. (2008)
Postpartum weight retention 6 mo after delivery (kg per kg of gestational weight gain)	Uniform			0.30 - 0.40	Baker et al. (2008)
Postpartum weight retention 18 mo after delivery (kg per kg of gestational weight gain)	Uniform			0.16 - 0.21	Baker et al. (2008)
HCB half-life (years)‡	Normal	6	0.9	4.2 - 7.8	To-Figueras et al. (2000)
Maternal lipids¶	Normal	1.0	0.21†	0.58 - 1.42	Borrud et al. (2010)
Volume of breast milk¶	Normal	1.0	0.17	0.66 - 1.34	Arcus-Arth et al. (2005)
Lipids in breast milk¶	Normal	1.0	0.28	0.48 - 1.52	Arcus-Arth et al. (2005)
Child sex	Bernouilli (p=0.5)				Assumed
Gestational age (weeks)	Normal	39	2	35-43	Assumed
Child weight¶	Normal	1.0	0.12	0.76 - 1.24	Kuczmarski et al. (2002)
Child lipids¶	Normal	1.0	0.15	0.70 - 1.30	Enzi et al. (1981), Butte et al. (2000)

^*Martin et al. (2012) reported the percentage of pregnant women across different age ranges as of 2002: 3.0%, 6.6%, 51.5%, 36.2%, and 2.6% were ages 15-17, 18-19, 20-29, 30-39, and 40-54 years, respectively. These proportions were used to estimate the best-fitting normal distribution; a distribution with a mean age of 25 years and a standard deviation of 6 years was selected.

^†Standard deviation calculated from the interquartile range (SD = 0.74*IQR).

^‡The SD was calculated assuming a coefficient of variation of 0.15 and the range was set to ± 2 SD.

^¶Parameters that fluctuate within individual simulations were varied using a multiplier with a distribution centered around 1.0, a standard deviation equal to the coefficient of variation and a range of ± 2 SD.