During pregnancy and lactation, the maternal body undergoes many changes in the regulation of appetite, body weight and glucose homeostasis to deal with the metabolic demands of the growing fetus and subsequent demands of providing milk for offspring. The aim of the current study was to investigate the consequences of one reproductive cycle of pregnancy and lactation on the long-term regulation of energy homeostasis. Mice that had gone through successful pregnancy and three weeks of lactation, or aged-matched controls, were weighed weekly until 8 weeks post weaning of their pups (reproductively experienced, RE). Mice were housed in Promethion Metabolic Phenotyping Cages (Sable Systems International), with or without access to voluntary running wheels, for the recording of metabolic and behavioural data. RE mice had significantly higher body weight than aged-matched control (CON) mice (25.09 ± 0.34 g vs 23.13 ± 0.43 g). While there was no significant difference in daily food intake, or the feeding response to exogenous leptin administration, RE mice were significantly less active than CON mice as measured by average daily xy beam breaks (33022 ± 1664 vs 49463 ± 6269) or average daily locomotion distance (146.9 ± 15.5 m vs 238.4 ± 28.6 m). Surprisingly, when exposed to a running wheel both groups has similar levels of daily running wheel activity (Control:8215 ± 580 m vs RE:6768 ± 705 m) yet daily locomotion (non-running wheel) distance was less in the RE mice compared to CON mice (102.2 ± 4.8 m vs 129.3 ± 10.2 m). Overall these data suggest that after weaning of their pups, RE mice maintain an increased body weight compared to aged-matched virgin mice, possibly due to lower activity levels, thus emphasing that pregnancy and lactation have long term consequences on body weight regulation in mothers.