The effects of body weight, body surface area, age and race on the pharmacokinetics of NGMN, NG and EE were evaluated in 79 healthy women using pooled data following single dose administration of NGM or mg / EE mg tablets in four pharmacokinetic studies. Increasing body weight and body surface area were each associated with decreases in C max and AUC 0–24h values for NGMN and EE and increases in CL/F (oral clearance) for EE. Increasing body weight by 10 kg is predicted to reduce the following parameters: NGMN C max by 9% and AUC 0–24h by 19%, NG C max by 12% and AUC 0–24h by 46%, EE C max by 13% and AUC 0–24h by 12%. These changes were statistically significant. Increasing age was associated with slight decreases (6% with increasing age by 5 years) in C max and AUC 0–24h for NGMN and were statistically significant, but there was no significant effect for NG or EE. Only a small to moderate fraction (5–40%) of the overall variability in the pharmacokinetics of NGMN and EE following Ortho Tri-Cyclen Lo Tablets may be explained by any or all of the above demographic parameters.