  We attempt to understand the fate of spacelike gravitational singularities in
string theory via the quantum stress tensor for string matter in a fixed
background. We first approximate the singularity with a homogeneous anisotropic
background and review the minisuperspace equations describing the evolution of
the scale factors and the dilaton. We then review and discuss the behavior of
large strings in such models. In a simple model which expands isotropically for
a finite period of time we compute the number density of strings produced by
quantum pair production and find that this number, and thus the stress tensor,
becomes infinite when the Hubble volume of the expansion exceeds the string
scale, in a manner reminiscent of the Hagedorn transition. Based on this
calculation we argue that either the region near the singularity undergoes a
phase transition when the density reaches the order of a string mass per string
volume, or that the backreaction of the produced string matter dramatically
modifies the geometry.
