The domain within your query sequence starts at position 5 and ends at position 171; the E-value for the 3Beta_HSD domain shown below is 3.6e-18.

LVTGGAGYIGSHTVLELLEAGYSPVVIDNFHNAIRGEDSMPESLRRVQELTGRSVEFEEM
DILDQAALQHLFKKHSFKAVIHFAGLKAVGESVQKPLDYYRVNLTGTIQLLEIMRAHGVK
NLVFSSSATVYGNPQYLPLDEAHPTGGCTNPYGKSKFFIEEMIRDLC

3Beta_HSD

3Beta_HSD
PFAM accession number:PF01073
Interpro abstract (IPR002225):

The enzyme 3 beta-hydroxysteroid dehydrogenase/5-ene-4-ene isomerase (3 beta-HSD) catalyses the oxidation and isomerisation of 5-ene-3 beta-hydroxypregnene and 5-ene-hydroxyandrostene steroid precursors into the corresponding 4-ene-ketosteroids necessary for the formation of all classes of steroid hormones.

GO process:oxidation-reduction process (GO:0055114), steroid biosynthetic process (GO:0006694)
GO function:oxidoreductase activity, acting on the CH-OH group of donors, NAD or NADP as acceptor (GO:0016616), 3-beta-hydroxy-delta5-steroid dehydrogenase activity (GO:0003854)

This is a PFAM domain. For full annotation and more information, please see the PFAM entry 3Beta_HSD