menses delayed may be due to hormonal imbalance,pelvic pathological disease,thyroid problems,anxiety,stress and lack of proper diet etsc.you already taking iui treatment.there may be hormonal imbalance which may be due to using medicine during treatment . you can expect to menstruate about 2 weeks after the IUI if you are not pregnant. If you are using progesterone vaginal suppositories, your period may be late even though you may not be pregnant.you should avoid stress and anxiety keep patience during treatment for proper result.you can follow 3 to 6 cycles of IUI are performed before moving on to other fertility treatments.