In this study there was no significant relation between HOMA- IR and menstrual pattern (p = 0.28).
In a survey on 57 morbid obese women the samples were in two groups. In group one the morbid obese women had not hirsutism or menstrual irregularity and group 2 had menstrual dysfunctions with or without hirsutism. Thyroid function tests, FBS and serum lipid profile in two groups had not significant difference but in group two HOMA – IR was significantly higher than group 1. They concluded that IR in morbid obese women can make menstrual irregularity even without elevated androgens [10]. But in our study in 82% of obese women with normal menstrual pattern and in 85.28% of obese women with abnormal menstrual pattern HOMA – IR was more than 2.5. On the other hand in some studies IR was not related with menstrual regularity [6].
The effectiveness of treatment with D – Chiro Inositol (DCI) in improving IR in patients with PCOS had been confirmed in several reports. In one retrospective study 47 women with PCOS were treated with DCI for 15 months. In 51.6% the serum AMH levels and IR indexes significantly decreased during the treatment. They concluded that DCI for treatment of PCOS makes improvement of IR and menstrual cycle irregularity [11].
In one study on biochemical characteristics of women with menstrual disturbances, the samples were 257 women with oligomenorrhea. Between women with oligomenorrhea 149 were hyper androgenic and 108 non hyper androgenic. They had 213 controls with normal cycles. Endocrine and metabolic parameters and IR were compared among different menstrual patterns. Hyper androgenic women with amenorrhea had higher levels of androgens and more lipid profile disorders than hyper -androgenic women with oligomenorreha. However in non - androgenic women with amenorrhea the degree of IR and metabolic disturbances were similar to hyper androgenic women with oligomenorrhea. They resulted that in women without excess levels of androgens menstrual disturbance does not correlate with severity of IR and metabolic disturbances [12].
In one survey on 137 women with PCOS 84.7% had hyperandrogenism, 84.7% had oligo anovulation and 89% had PCO. 69.4% had classic phenotype of PCOS, 15.3% had ovulatory phenotype, 15.3% had normo androgenic phenotype. 71.4% of subjects were IR and IR frequency differed among phenotypes (p < 0.001). In normo androgenic phenotype there was not IR case and resulted that in normo androgenic PCOS women there is not IR and are different from other PCOS cases [13].
There is a survey on 70 non obese patients with hirsutism, to find the role of IR on hirsutism. The samples were in three groups. 30 women with idiopathic hirsutism (IH) and 20 with hirsutism due to PCO and 20 healthy controls were assessed.
16 with IH and 17 with PCOS had IR. There was significant difference in fasting lnsulin levels and HOMA – IR in three groups, but there was no significant difference between IH and PCOS patients. Women with android fat deposition had higher fasting insulin levels and HOMA – IR. They concluded that IR occurs in non obese patients with IH, and may be related to android obesity [14].
By a research on 976 Korean people the cut of points for describing insulin resistance was calculated. The cut off point for fasting insulin was 12.94 mU/ml, for the quantitative insulin sensitivity check index (QUICKI) was 0.32 and for HOMA – IR was 3.04 [15]. In our research we described the IR as HOMA – IR > 2.5. There is heterogeneity for IR definitions and in different studies HOMA – IR index cut off values to define IR was different. The IR cut off range in different studies was between 2 to 3.5 [16], and was dependent to gender, race, age, obesity, smoking and etc.
Triglyceride and glucose index (TYG index) also have been suggested for diagnosis of insulin resistance. In a review article with 69922 participants the TYG index was evaluated by HOMA as reference test. The highest specificity was 99% with HOMA – IR with a cut off value of 4.68 [16]. In one study optimal insulin resistance cut off was 2 [17]. In another study IR cut off was 2.8 [18]. Considering various normal IR cut off definitions, the relation between different variables is not reliable.
We concluded that the role of IR in obese women, on menstrual pattern is not clear.
Not only obesity by itself but also obesity with combination with hirsutism or IR does not have significant relation with menstrual pattern.