interstage       
adjective [ before noun ] (also inter-stage) uk/ˌɪn.təˈsteɪdʒ/ us/ˌɪn.t̬ɚˈsteɪdʒ/
 阶间的;级际的
between the different stages in a process, especially a series of medical treatments or operations
  They arranged an interstage visit to the clinic.
 These results highlight the importance of interstage monitoring. 这些结果突显了阶间监测的重要性。 
 - More examples
- Little information is available about growth rates for children in the interstage period.
- Outpatient follow-up during the interstage period is quite rigorous.
- Monitoring of oxygen and weight change has been associated with improved interstage survival.
- Some infants changed their feeding regimen during the interstage period.