In very broad terms, fertility diagnosis starts with attempting to determine the impact of several major factors for the male and female partners with testing and diagnosis:
Age The impact of aging on female reproduction is well known. Overall, a woman’s age is one of the best predictors as to whether or not she will conceive with her own eggs. After about age 43, the odds of this fall low enough (and miscarriage and chromosome abnormality rates raise high enough) that the likely best option is egg donation. After about age 35, when declines in natural fertility become sharper, many women are simply experiencing what we call age-related sub-fertility. That is, there is no specific fertility problem other than as we get older, the egg being ovulated may be less capable of sustaining a pregnancy.
Ovulation Without ovulation, there is no conception. Regular monthly menstrual cycles equate with ovulation. Polycystic Ovarian Syndrome, Hypothalamic Anovulation, Luteal Phase Insufficiency and problems with other hormones such as thyroid hormone or Prolactin may interfere with ovulation. Most women will ovulate well into their 40’s and even 50’s but it is the quality of the eggs being ovulated that is critical. Young women that do not ovulate regularly can usually be induced to ovulate with either oral or injectable fertility medications.
Ovarian Reserve This is the concept of what is a woman’s reproductive potential and what are the chances that a woman will be able to conceive a healthy, viable pregnancy with her own eggs? We test for ovarian reserve with blood tests (Cycle day 2-3 FSH and Estradiol and random AMH) as well as an ultrasound to look at the ovaries.
Tubal Status Infection, post-surgical scarring or the disease endometriosis can cause fallopian tubes to be blocked, kinked or distorted. This prevents eggs and sperm from getting together and can lead to tubal (ectopic) pregnancy. The dye test HSG (hysterosalpingogram) is the only non-surgical way to evaluate the patency of the fallopian tubes – that is to determine whether or not the tubes are open.
Uterus and Endometrial Lining Fibroids, polyps, intra-uterine scarring from prior surgery are some of the things that can cause the uterus and it’s lining to be abnormal and to cause an embryo to fail to implant. Plain ultrasonography, performed just prior to ovulation, can often be sufficient to diagnose any problem. However, if not perfectly clear, sono-hysterogram (ultrasound done while putting sterile saline fluid into the uterus) or hysteroscopy (surgery to look inside the uterus) can be performed. Most of these problems are surgically correctable.
Genetic Some patients carry genetic diseases that can cause infertility, such as Fragile X syndrome. Some women (and men) can have rearrangements of their chromosomes such that their eggs and sperm can have abnormal chromosomes and this can lead to repeated miscarriage or infertility. These problems are rare but do exist.
Endometriosis This is one example of a disease of the female reproductive years that is strongly associated with infertility. Surgery is the only way to make a definitive diagnosis. But surgery is minimally helpful in improving the odds of conception even if endometriosis is found and treated surgically. This is because the disease has a high recurrence rate. For this reason, it is not common to perform surgery to go looking for endometriosis. Therefore, many women that are carrying the diagnosis of “unexplained infertility” may actually have endometriosis but it does not change the infertility treatment plan.
Sperm Count The basic sperm count, achieved by masturbation and examination of the sperm 2-5 days after abstinence is one of the mainstays of making a diagnosis, and should be done even when there is a female factor identified. As many as 40% of couples with fertility problems have issues affecting both partners.
Sperm Function The ability of a sperm to penetrate a human egg is an important issue. Low sperm counts and low motility on the Semen Analysis can often predict whether the sperm that are present are sufficient in numbers and activity to reach the eggs, and then bind to and penetrate them. Other than mixing eggs and sperm in a dish at the time of In Vitro Fertilization, there is no definitive way to prove that sperm are functioning properly. In rare cases, some men with completely normal Semen Analysis numbers may be found to have sperm that cannot bind to human eggs. Unfortunately, this is usually discovered at In Vitro Fertilisation.
Sperm DNA Integrity There has been much recent interest in evaluating patients with unexplained infertility, repeated reproductive failure and recurrent miscarriage by evaluating the male’s sperm for DNA fragmentation. These tests are not reliably 100% predictive but may indicate in these rarer cases, whether or not the sperm, rather than the egg, is leading to the fertility problem.
Age Some studies have suggested that advanced male age (usually over age 50) may lead to increased infertility and increased rates of miscarriage. The data in the literature on this is mixed: some studies showing paternal age to have an effect and some not finding it to be very predictive. If there is an effect of paternal age, it may be a small effect.
Genetic Men with Klinefelter’s syndrome (47 XXY chromosome makeup instead of 46XY), men with deletions of parts of the Y chromosome, men with balanced translocations, and a few other rarer genetic abnormalities are going to have male infertility.
Sexual Dysfunction Although this might primarily have to do with one or the other partners in a couple (e.g. erectile dysfunction in men, vaginismus in women), oftentimes, sexual dysfunction is a couple’s problem and must be addressed by assessing both partners.
Unexplained Infertility This is the diagnosis given when all the other tests are normal. Many couples failing to conceive after 1-2 years of trying, with all the usual tests coming up normal, may actually have age-related sub-fertility or endometriosis. On the other hand, there may be other diagnoses or medical problems that we have just not come to understand yet. The most recent diagnosis of “Decreased Ovarian Reserve” was only elucidated about 20 years ago.