The causes of lower abdominal pain in women with ovarian teratomas are complex. Firstly, as the teratoma grows in size, it can, due to gravity, pull on surrounding ligaments, causing pain on one side of the lower abdomen. When the teratoma is particularly large, it can also compress nerves in the pelvis, leading to neuropathic pain. Moreover, teratomas are heterogeneously textured. If they are quite mobile and not adhering to surrounding tissues, sudden changes in body position, or an increase in uterine size during the mid-pregnancy, might shift the position of the teratoma. This can lead to torsion of the stalk, causing local ischemia and hypoxia, and resulting in acute lower abdominal pain.