Causes of Infertility with Dr. Mills
May 04, 2022
In Part II of our three part series on fertility, Dr. Genevra Mills, an obstetrician gynecologist with a specialty in reproductive endocrinology and infertility with three kiddos of her own, discusses with us causes of infertility. She gives us a most helpful breakdown of the main reasons for infertility in both the male and female partner.
Often causes of infertility can be somewhat obvious and easily identified, and most times patients have an idea that something's going on even before they get to that point of twelve months of trying without success. Here are the main medical conditions that can affect fertility between heterosexual partners.
Issues with Ovulation
There are multiple reasons why an egg may not be released every month, and issues with ovulation make up about 15% of a couple’s cause of infertility.
- Polycystic Ovary Syndrome (PCOS): the first and most common ovary dysfunction is Polycystic Ovary Syndrome in which ovaries have too many follicles in them causing them to compete with each other hormonally and signalling wise, resulting in no ovulation.
- Issues with the Hypothalamus or Pituitary Gland: these are glands in your brain that are responsible for talking to your ovaries and telling them what they do. Issues in the hypothalamus or pituitary glands can result in hormonal issues preventing ovulation, and are most often identified using blood tests.
- Thyroid Issues: a history of thyroid issues, either hypothyroidism or hyperthyroidism resulting in Graves' disease or Hashimoto's thyroiditis for example, coupled with a decrease in regular periods, can cause an issue with ovulation.
- Early Menopause: a family history of premature ovarian insufficiency (early menopause) is important to consider.
- Lifestyle: sometimes things about your lifestyle can give us some hints, such as disordered eating or overeating disorders, being a very active person (ie. competing in competitive sports), or a deficiency in how much you're eating versus how much you're exercising. Being under a lot of stress and/or systemic illnesses which place stress on your body can also be factors to consider.
Issues with Pelvic Anatomy
Issues with the anatomy of the uterus or fallopian tubes, or something wrong with the pelvis in general that has led to scar tissue building, accounts for about 30%-35% of the reasons people are not able to get pregnant.
- History of Sexually Transmitted Infections (STIs): STIs such as Chlamydia and Gonorrhea, especially if they are present for a while asymptomatically and therefore go untreated, can cause scar tissue in the fallopian tubes and are the biggest cause of tubal factor infertility.
- Pelvic Inflammatory Infection: having had a pelvic inflammatory infection in the past where you've had a tubal, ovarian abscess that's been treated can be another big risk factor.
- Endometriosis: especially severe endometriosis can distort your anatomy by causing scarring in your tubes or just making it so that your tubes are not necessarily in the right position in relation to your ovaries.
- Abdominal Surgery or Ruptured Appendix: if you've ever had any type of operation such as bowel surgery, hernia repairs, or even a ruptured appendix can lead to issues.
- Inflammatory Bowel Disease: for similar reasons as above, having inflammation of the bowels can cause issues due to scar tissue.
- Chemotherapy or radiation treatment for cancer: if you’ve undergone either of these at any time in your life, those are other reasons why you should potentially seek fertility support sooner as they can sometimes be toxic to the ovaries and can deplete the number of eggs or quality.
- Abnormal Uterus: there are a wide variety of anomalies, for lack of a better term, in the creation/growth phase of the uterus that can cause issues with infertility, although some abnormalities may not affect fertility at all.
- Fibroids: fibrates are little, benign growths inside the uterine muscle that can happen anywhere from inside your uterine cavity, called an intracavitary fibroid, all the way to the very outside, which is called a pedunculated fibroid. We really only worry about fibroids from a fertility perspective if the fibroid impinges or touches on the endometrial cavity or is inside it, distorting it.
Problems with the male partner, or the person with the sperm, accounts for between 35%-40% of the reason why couples don't get pregnant. The issues can range from a decreased number of sperm to sperm abnormalities.
Physicians look for four general things when doing a sperm test, or semenanalysis:
- How many sperm are there?
- a sample is about 15 million per milliliter or more
- How well do the sperm swim in general?
- About 40% of them should be swimming
- How many of them swim in a forward direction?
- Only need about 32% of sperm swimming in a forward direction
- What do the sperm look like together?
- Abnormalities on their heads or tails - only about 4% of sperm being produced look strictly normal
Factors contributing to issues could be any of the above or a combination, as caused by:
- Varicocele: varicose veins in the scrotum, increasing the blood flow and heating up the testicle oftentimes causing the amount of sperm and motility to decrease
- History of an undescended testicle
- Significant testicular trauma or surgery
- Sexually Transmitted Infections (STIs) such as Chlamydia and Gonorrhea
- History or family history of Cystic fibrosis: sometimes causing gene mutations
- Y Microdeletion: a little part of the Y chromosome that is either missing or isn't functioning properly that means men don't make sperm.
There's a little sliver of the pie that doesn't fit into any of the above categories, and those are couples who fall into what is called unexplained infertility. An unexplained infertility is when an egg has been released every month, we have normal or near normal sperm, and we have at least one fallopian tube and a normal uterus, and no pregnancy occurs. About 10%-15% of couples struggling with infertility fall into this category.
This just goes to show us that no matter how much we know up until this point and how much we can do to make a difference, there's still probably just as much, if not more, that we don't know!
But tune in in the following weeks where we will be continuing our conversation about fertility with Dr. Mills! Until then, feel free to follow her on Instagram, and check out The Pregnancy to Parenthood Podcast Series! For the low, one-time cost of $47, get full access to over 40 informative episodes supporting you week by week, focused on the trimester and stage of pregnancy you are in. Tune in every week, or binge listen all at once and come back to the episodes you found most helpful as you move through pregnancy to parenthood!
She Found Motherhood Podcast;
What you need to know about PCOS and fertility!