〔Abstract〕 To investigate the effect of environmental enrichment on cognitive impairment and hippo- campus GAP-43 changes induced by exposure to Obstructive Sleep Apnea-Hypopnea Syndrome (OSAHS) during the period of late pregnancy in mice , and to explore relative inflammatory pathway mechanism . Methods The ex- perimental group of C57BL/6J pregnant mice were exposed to an intermittent hypoxic environment for 7 consecutive days starting from gestational day 15 . The corresponding offspring were then placed in an enriched environment from postnatal day 21 to 2 months of age (designated as OSAHS + EE group) or in a normal environment (designat- ed as OSAHS group) . Pregnant mice in the control group were maintained in a normal oxygen environment , and their corresponding offspring were placed in an enriched environment (designated as Control + EE group) or a nor- mal environment (designated as Control group) at the same ages . The spatial learning and memory ability of the mice was assessed by Morris water maze at the age of 2 months . The mRNA levels of NF-kB , NLRP3 and GAP-43 in the hippocampus were detected by real-time fluorescence quantitative PCR , and the protein levels of NLRP3 and GAP-43 in the hippocampus were detected by Western blot. Results Compared with Control group , the swimming distance increased (P < 0. 01) , and the percentage of swimming distance in target quadrant decreased (P < 0. 01) in OSAHS group . The level of NF - κB mRNA , NLRP3 mRNA and protein in the hippocampus was increased , and the level of GAP-43 mRNA and protein was decreased (P < 0. 01) . Compared with the Control group , there were no significant differences in swimming distance , percentage of swimming distance , NF-κB mRNA , NLRP3 mRNA and protein content in the OSAHS + EE group . Conclusion OSAHS during pregnancy impairs the learning and memory ability of offspring mice and reduces the level of GAP-43 protein . The mechanism may be related to the in- crease of NF-κB /NLRP3 level , and environmental enrichment can improve the damage .