The accumulation of insulin in the bloodstream elevates androgen levels; the resulting hormone imbalance will negatively affect ovulation. When women do not ovulate, they may menstruate less frequently, have irregular cycles and, in some instances, they may not menstruate at all. If an egg is not released into the uterus, conception will not occur. While it is more likely for overweight and obese women to experience insulin resistance and PCOS, women of a normal weight can be affected too.