Ideally the female should be seen initially on cycle day 2 or 3 of her menses, and blood can be drawn for hormonal evaluation.  I like to request FSH, LH, TSH, free T3, free T4, prolactin, estradiol and total estrogen and antichlamydial antibodies.  The results of these tests will give a reasonable picture of her potential to ovulate and conceive.  Frequently I see patients who have been referred to me, and I find that have low thyroid function or elevated prolactin, and can conceive after minimal treatment.

I consider this step crucial in to the work-up because if a small problem remains undetected you can spend a lot of time and effort without finding the cause of infertility.  If the woman is 40 years or older I strongly recommend additional testing to see her potential to ovulate and conceive.