  Various surveys of low-mass binaries in star forming regions have been
performed in recent years. They reached opposite conclusions concerning
possible binary excesses in some of these associations. I develop a consistent
method to reanalyze all these studies, so that I can compare all data
consistently, and understand the previous findings. I also report the detection
of five new companions to Taurus members.
  It appears that binary fraction in Taurus exceeds the main sequence value by
a factor of 1.7 in the range 4-2000 AU. The companion star fraction in this
separation range is the same as the overall main sequence fraction. Ophiuchus,
Chameleon, and possibly Lupus show similar excesses, although with lower
confidence levels. Binaries in Ophiuchus seem to have larger flux ratios
(towards faint companions) than in Taurus.
  It appears very unlikely that all very young star forming regions have binary
excesses. The binary fraction seems to be established after $\sim$ 1 Myr, but
the precise nature of the difference between various regions is still unclear
(overall binary fraction, orbital period distribution). It is not currently
possible to put constraints on the binary formation models: higher angular
resolution and larger sample sizes will be required.
