I have sciatica that radiates to my little toes, has become progressivly worse in the past yr worse on period and when sitting. what r possible causes?

Nerve impingement: At your age, likely a herniated disk, annular tear of one of your lumbar discs, sacroiliitis or possibly piriformis syndrome.

At your age most : Likely from disc problem but could also be related to spine deformity known as spondylolisthesis or even soft tissue problem like pyriformis syndrome. At this time, if the symptoms warrant, see your doctor for evaluation or referral to spine specialist. Siiting is 4x body weight across lower back discs & with your cycle there may be water retention which will affect already inflamed tissues.

Sciatica: Sciatica is pain in the distribution of the leg as a result of an irritated nerve or facet joints or other injury typically in the lumbar spine (low back) which are caused by herniated disks, spinal stenosis or degenerative disc disease, etc requiring further evaluation by a spine specialist and may be candidate for facet injections/radiofrequency ablation and epidural steroid injection.