  We present the results of a study of young unresolved stellar groupings
(clusters, OB associations, and their complexes) associated with HII regions,
based on the coupling of spectroscopic, photometric and H{\alpha}
spectrophotometric observations of star formation regions. Along with our own
observations, we use a part of the spectroscopic and H{\alpha} data from the
literature and open databases. The study is based on the catalogue of 1510 star
formation regions with ages ~10-20 Myr in 19 spiral galaxies, compiled by us
earlier. We study the morphology of stellar groupings and their relation with
the associated H{\alpha} emission region. Extinctions, gas chemical abundances,
and sizes of star formation regions are measured. Using numerical SSP models
computed for metallicities fixed from observations to intrinsic colours of the
studied star formation regions, we estimated ages and masses of stellar
population of 400 young stellar groupings. Different relations between
observational and physical parameters of the young stellar population in star
formation regions are discussed.
