Infertility refers to being unable to get pregnant. The average diagnosis comes after a period of assessment (1 year or more) with the couple trying to get pregnant. In some cases, a woman may get pregnant but won’t be able to carry the fetus to term (miscarriage), and this is also noted under the same diagnosis of infertility.
According to modern research, 10-15% of all US couples deal with this concern. Approximately 33% of these cases involve women-related problems concerning fertility. While another 33% includes men-related issues. The remaining 33% consists of a combination of men and women-related problems.
Timing and interaction of many factors come into play when looking at fertility. Hormones, both men’s and women’s, constitute a big part of this equation. These hormones include those produced by a man’s testicles, a woman’s ovaries, and glands like the pituitary, hypothalamus, and thyroid.
When it comes to pregnancies, a woman has to develop an egg in one of the ovaries and then release it. Women are born with a set number of eggs (or oocytes), and each one has its own spot in the ovaries, nesting in a cavity filled with fluid, called a follicle. When a healthy female is born, she will have approximately 1-2 million follicles, but most of these degenerate once puberty hits. As a result, there are about 200,000-400,000 viable follicles left. When a woman starts entering the all-important reproductive years, the numbers dwindle further so much that only about 400 mature eggs are ever released. Most women release about one mature egg per month.
A woman’s menstrual cycle kickstarts the follicle-stimulating hormone (FSH) that causes the follicles to mature a few at a time. During this stage, typically, only one follicle tends to dominate over the rest. This is when estradiol production begins to rise and hits top gear around day 14 out of the cycle. The estradiol causes the uterine lining to thicken and acts as a catalyst for hormone production of gonadotropin-releasing hormone, FSH, and luteinizing hormone. When these hormones come into effect, the mature egg is released, and that’s what begins the ovulation process.
The mature egg begins to move through the fallopian tube and, if sperm are present, eventually gets fertilized. If fertilized successfully, the embryo begins to form and move into the uterus before finally settling into the endometrium (or the lining of the uterine). When the embryo starts to develop, the newly formed placenta supplies nourishment and other support during the gestation period. A hitch in any of these processes could spur problems with infertility. In the end, deciphering the things that cause infertility may be complicated, while other times, it may be relatively easy to identify and address the cause.
Main Causes of Infertility
It starts with something as simple as age. Couples that are trying to conceive during their 30s or 40s see a rise in these issues.
The best time for a woman to conceive is during her early 20s before fertility substantially declines by age 35 and even more after 40. When a woman reaches menopause, she doesn’t have many functioning eggs available.
When it comes to men, their number and motility of sperm decreases, which reduces the likelihood of pregnancy. There are other relevant age-related concerns for men, such as low testosterone levels, erectile issues, ejaculation trouble, and prostate concerns.
Along with age, other relevant factors to keep in mind for men and women include:
- Too Much Exercise
- Unhealthy Habits (i.e., Smoking, Alcoholism, Drugs)
- Significant Medical Conditions (i.e., Diabetes)
- Exposure to Chemicals/Toxins
- Exceedingly Overweight/Underweight
While each of these may play a role in causing infertility, there are times when the root cause is unknown. These conditions may restrict sperm movement, affect ovulation, or affect fertilization or implantation of the egg.
For women, here are some of the leading conditions that can cause infertility:
- Polycystic Ovary Syndrome (or PCOS) – Impedes the Releasing of Mature Eggs
- Pelvic Inflammatory Disease (or PID) – Blocks Fallopian Tubes Due to STDs
- Primary Ovary Insufficiency (or POI)
- Fibroids in the Uterus
- Irregular Hormone Levels (FSH, LH, Estrogens)
- Eating Disorders
- Autoimmune Disorders (i.e., Antiphospholipid Syndrome)
- Gluten Intolerance
For men, the following conditions can impact their fertility:
- Irregular Hormone Levels (Testosterone, FSH, LH)
- Erectile Dysfunction
- Low Sperm Count, Clumped Sperm, Abnormally-Shaped Sperm, Poor Sperm Movement (Motility)
- Obstructions Preventing Ejaculation
- Enlarged Veins Near the Testicles (Varicoceles)
- Prolonged Fever
- Injured Testicle(s)
- Mumps Infection (Inflamed Testicles)
- Excessive Heat Near the Testicles
- Klinefelter Syndrome
Lab Testing for Women
It’s best to start with relevant blood tests to assess the hormone levels that cause infertility.
These can include:
In some cases, changes in thyroid and/or pituitary function can impact the menstrual cycle and ovulation process. Blood tests may help spot irregularities when it comes to thyroid function (Free T4 and/or TSH) along with steroids (DHEA-S, Testosterone) and while also shedding light on androgen levels.
There are specific imaging techniques that can be deployed to spot physical concerns that impede fertilization or healthy pregnancies. These imaging procedures include ultrasound sonograms, x-rays, and fiber-optic endoscopies, all to help locate abnormalities such as abscesses, tumors, fibroids, and/or polyps.
Lab Testing for Men
For men, the diagnostic process involves a thorough look through their medical history and a physical exam to spot any abnormalities. Depending on what’s observed, the examination may also involve the use of a trans-rectal ultrasound (TRUS) to find abnormalities that can include blockages affecting the release of sperm during ejaculation. Note: an absence of sperm (azoospermia) may be due to a lack of seminal vesicles or vas deferens.
Semen Analysis is a foundational test used to aid in diagnosing infertility in men. The semen is collected and evaluated to spot potential defects in the shape, number, or movement (motility) of sperm.
Blood tests can be used to assess hormone levels. These include: