“How does one know that she has a deficiency in DCI-IPG? And how do you correct this disorder?”
The only way to definitively determine whether you are functionally deficient in DCI-IPG is to do a muscle biopsy. I don’t believe that this is performed clinically at present, as it’s a reasonably invasive test, but there have been a couple of studies which have performed muscle biopsies from live patients and obtained samples during autopsies of Type II diabetics as part of their investigation into the role of DCI-IPG in insulin resistance.
From a study published in 2008 in the Journal Metabolism Clinical and Experimental by Cheang et al:
“Significantly decreased muscle DCI-IPG bioactivity and decreased total DCI content have been noted in needle biopsies  and autopsy specimens  from subjects with type 2 diabetes mellitus compared with controls. In addition, DCI-IPG (or P-type IPG) has been shown to be decreased in human term placentas in preeclamptic individuals, who also concomitantly exhibit decreased insulin signaling, when compared with healthy women .”
The other studies referred to in the paper are:
 Kennington AS, Hill CR, Craig J, et al. Low urinary chiro-inositol excretion in non–insulin-dependent diabetes mellitus. N Engl J Med 1990;323:373-8.
 Asplin I, Galasko G, Larner J. Chiro-inositol deficiency and insulin resistance: a comparison of the chiro-inositol- and the myo-inositol–containing insulin mediators isolated from urine, hemodialysate, and muscle of control and type II diabetic subjects. Proc Natl Acad Sci
 Scioscia M, Gumaa K, Kunjara S, et al. Insulin resistance in human preeclamptic placenta is mediated by serine phosphorylation of insulin receptor substrate-1 and -2. J Clin Endocrinol Metab 2006;91:709-17. U S A 1993;90:5924-8.
I hope this answers your question.
Clinical signs such as better energy levels, reduced appetite (or even increased appetite) are a good indicator that you do have a degree of DCI deficiency, either through a lack of dietary myoinositol or an inability to convert myoinositol into DCI. Hopefully as your treatment progresses you will resume menstruating. Some women have found that their menstrual cycle either shortens, or if it has been absent, returns within their first 2-4 weeks of treatment with DCI, even if it’s been absent for years.
There is no known way to correct the disorder, in fact, the disorder itself is still being isolated. It appears that some women (especially those from the studies performed in South America) have a deficiency of DCI that is corrected by dietary supplementation with d chiro inositol. A more recent study, in fact the one I quoted from above, resulted in findings that indicate that there is another mechanism of action in IR which may involve a functional deficiency in DCI-IPG which is NOT corrected by dietary supplementation. It’s hard to say, as the study was cut short at only 6 weeks due to them running out of DCI and they did not test levels of testosterone, cholesterol, triglycerides etc – the things that have been found to consistently improve in prior studies.
Insulin resistance, which is really the root of the problem when it comes to PCOS, is a complex problem and there are many things that you can do to improve it. Please check outhttp://www.pcosinfo.wordpress.com/treatments/natural andhttp://pcosinfo.wordpress.com/news-research for some ideas or feel free to write back with any more questions you may have.
Well this is rather a long-winded and technical response but it is a complex issue. I hope it’s been helpful to you.