There are a variety of fertility tests that can be done. A gynecologist can order some of these tests, but in general it makes sense to see a specialist who can order all necessary tests and treatments. These generally involve a medical evaluation, assessment of the uterine cavity and of the fallopian tubes, assessment of the male partner, and testing for ovulation. Additional tests may involve laparoscopy, assessment of cervical mucous, testing for polycystic ovarian syndrome, and in older women some test of ovarian reserve. In many cases no apparent cause will be found and the couple is said to have unexplained infertility. This does not mean that you cannot conceive; it just means that the cause of your infertility is not readily apparent. There are, in fact, many effective treatments for unexplained infertility.

Ovarian Reserve

Your doctor is able to test your body's number of viable eggs. This is done with a blood test on the second, third, or fourth day of your cycle. The blood test evaluates the levels of the hormones FSH and estradiol in your blood. High levels of the FSH hormone indicate low levels of ovarian reserve. Your physician may also have you take what is called the Clomid challenge test. You take the fertility drug Clomid, which stimulates ovulation, and then a blood test is done, measuring how well your body responded to the drug. Ovarian reserve can also be measured by ultrasound.

Progesterone Levels

Progesterone is the hormone that is released by a woman's body after ovulation and that helps prepare the uterus for implantation. Progesterone levels can be tested with a blood test after ovulation. Following ovulation, the area in the ovary from which ovulation occurred begins to produce progesterone, which prepares the uterine lining for the implantation of a fertilized egg.

Abnormal levels are known as luteal phase defect (LPD). Luteal phase defect may be suspected if your basal body temperature does not remain elevated for the usual twelve days after ovulation or if your menstrual cycles are short. Diagnosis is made by measuring post-ovulation progesterone levels or performing a timed endometrial biopsy.

Thyroid Levels

The thyroid is a gland in your neck that regulates hormone activity in your body. If your thyroid is not functioning properly, it can make it difficult to get pregnant. A simple blood test will check your level of TSH (thyroid stimulating hormone). If TSH levels are high it means you are thyroid deficient (hypothyroid), which can be corrected with thyroid replacement medication. This is important because there is evidence that even if the woman is only mildly hypothyroid, it can affect a baby's brain development.

If TSH levels are low, it means you are making too much thyroid hormone (hyperthyroid). There are options involving medication, radiation, or surgery to suppress the levels. The American Thyroid Association recommends that all people over age 35 get their thyroid levels checked at least once every five years. Any women contemplating pregnancy should have a preconception TSH test performed.

Pelvic Ultrasound

Pelvic ultrasound exams are used to check the condition of the uterus, tubes, and ovaries, and to track development of the follicle — the beginning stages of the egg. A woman will be asked to come in for several ultrasounds at the beginning of her cycle. These ultrasounds are usually done with a probe in the vagina and are not painful. The physician can watch development of the follicle and determine if a woman is ovulating. Ultrasound is also used with injectable fertility drugs to make sure there are not too many eggs to avoid a pregnancy with higher-order multiples.

Hysterosalpingogram

A hysterosalpingogram (HSG) is a test that is done to determine if there is any blockage in the fallopian tubes. The test is done at a hospital or radiology lab. A thin catheter is inserted through the cervix and into the uterus. Dye is then sent up through the catheter to fill the tubes. The passage of the dye is observed through X-rays. If the dye can't get all the way through a tube, it could indicate blockage. The test can cause some cramping but is not very painful.

There is some evidence that an HSG can clear mucous blockage from the tubes. A woman's fertility is increased in the months following an HSG.

Hysterosonography

Sometimes sterile saline will be injected into the uterine cavity, followed by pelvic ultrasound (hysterosonography). This enables the endocrinologist to check for uterine cavity shape, fibroids, or endometrial polyps. Hysterosonography may be used in addition to HSG.

Sperm Analysis

A sperm analysis is a normal part of any infertility workup. The male partner is asked to provide a sample of semen, in which the sperm is then counted and analyzed for mobility. Normally, the sample can be collected at home and brought into the lab. According to the American Society for Reproductive Medicine, male infertility contributes to 30 to 40 percent of infertile couples, so it is a factor that is always considered.

Endometrial Biopsy

If the physician suspects there is a problem with the development of the lining of the uterus (luteal phase defect, or LPD), a biopsy can be performed. A sample of endometrial tissue is taken in the doctor's office and is then analyzed. There are several different methods that can be used to take the sample.

Laparoscopy and Hysteroscopy

Laparoscopy is outpatient surgery performed with a small incision. A camera is inserted into the abdomen through the incision. This type of laparoscopy allows the physician to examine the uterus, ovaries, and tubes to determine if there is any abnormality.

A hysteroscopy is a camera passed through the cervix up into the uterus to examine the inside of the organ. These two procedures can be used as diagnostic tools but can also correct problems through surgery as well.