Infertility is the inability of a couple to achieve conception despite having adequate unprotected sexual intercourse (at least three times a week) for one year. Estimates of the number of couples affected by infertility In America approach 5 million. Similar values have been obtained worldwide as well.
The definition above in itself makes a diagnosis of infertility, however further work-up is obviously needed in reaching a diagnosis of the cause of the infertility, which may be due to female factors, male factors or a combination of both. Identifying the source of a couple's infertility involves a history, physical exam, lab work, imaging studies and sometimes, surgery.
History and Physical Exam
Some factors in the history may be a pointer to the reason for infertility in a couple. Habits such as alcohol intake and smoking may have an effect on a couple's fertility. The temperature of the scrotal sac is a degree lower than that of the rest of the body. This is essential for optimal functioning of the testes. Conditions that may increase the scrotal temperature, such as wearing of tight underwear, hot baths, or presence of a varicocele (enlarged veins within the scrotum), need to be elucidated from the history and physical exam. The use of any medications or recreational drugs needs to be found out as these may also affect fertility.
Seminal Analysis
Abnormalities in sperm mobility, structure or numbers is a common cause of male infertility and this can easily be discovered by a simple laboratory test called seminal analysis. It is often the first line of investigation for males. The man provides a sample of his semen after 2 days of abstinence; this is commonly obtained by masturbation. The semen is then analyzed by viewing under a microscope to determine the sperm count; normal values being about 20 million per ml of the ejaculate. Presence of abnormal shapes and motility of the spermatozoa are also checked for.
Hormone Assays
Women with a hormonal basis for their infertility may have irregular menses, milky discharge from the breasts, be under extreme stress or be underweight or overweight. Some may however have none of these situations. Blood tests are done at specific intervals of the menstrual cycle to measure the levels of some of the key hormones involved in regulating the reproductive cycle. By correlating the levels with the time of the cycle, specific diagnoses can be established. Examples of some of the conditions that can be identified with hormone assays include polycystic ovarian syndrome, premature ovarian failure, hyperprolactinaemia and hypogonadism.
Hormonal causes in men are rare; however for men whose seminal analysis reveals extremely low sperm count, similar hormone assays may be carried out to find out the cause of the low sperm count.
Imaging Studies
Imaging studies are used in diagnosing infertility as a result of obstacles to transport of the egg and or sperm such as blocked fallopian tubes, ashermann's syndrome(a condition in which the cavity of the uterus is obliterated) , fibroids and a host of other conditions. The most common imaging modality used in assessing tubal patency is the hysterosalpingogram or HSG for short. This involves passing a dye through the cervix and into the uterus and fallopian tubes. X-rays are then taken and it shows the patency or otherwise of the tubes and uterus. It also helps show distorted tubes. Other studies include a hysterocontrast sonography; this is similar to an HSG except that instead of x-rays, a sonogram is used to visualize the organs after the dye has been passed. Another is laparoscopy plus dye test which is a kind of mini surgery in which an instrument, called a laparoscope, is passed through a small cut made on the abdomen into the pelvis to directly visualize the reproductive organs. A dye is also passed to check for the patency or otherwise of the tubes. The latter two have the advantage of not involving radiation and a laparoscopy also has the added advantage of possible intervention if any abnormality is discovered.
Again in men, mechanical factors are uncommon, so imaging studies are not often performed. Rarely, if a man is discovered to have a condition of excessive prolactin affecting his sperm numbers, a brain scan may be needed to determine the source of the excess hormone.
By and large, these are some of the general investigations done to establish the reason behind infertility; other more or less sophisticated procedures may be needed depending on each individual situation. The important thing is for physicians treating affected couples to arrive at an accurate diagnosis so appropriate, timely intervention can be pursued.