A Piece of the Pie: What Causes Infertility?
Finding out that you have infertility is no piece of cake. It can knock you, shock you, and rock you in a way nothing else can. Why me? What did I do? How did this happen? The questions are endless. And while we may not be able to give you individual answers (at least not right now!), we can tell you what is most likely (in percentages and rates) to be hampering your efforts.
Infertility and its various causes (e.g., low ovarian reserve, ovulatory dysfunction, tubal damage, uterine issues, sperm abnormalities) are often depicted in the medical literature and medical textbooks as a pie chart. And a pie chart for all of you who have been away from math and statistics for some time is a circular statistical graph that is divided into slices. Each slice represents a different piece of the overall pie (a.k.a. the problem you are analyzing). Therefore, the bigger the piece, the bigger its contribution to the issue at hand.
Whether you prefer apple, blueberry, or peach, close your eyes, and picture a pie. Now substitute infertility for whatever fruit you are envisioning, and let’s cut it up.
~ 35% of infertility is “female related.”
~ 25% of infertility is “male related.”
~ 10% of infertility is unexplained.
~30% of infertility is due to both female and male issues (a.k.a. combined).
Keep in mind that percentages are like pieces of pie; cutting is not an exact science. Depending on the study or the reporting agency, numbers can be slightly higher or lower.
Now it’s pretty rare that you go to a party and there is only one dessert (or pie) option. How can you leave the blueberry crumble behind when walking away with that peach cobbler! The same goes for infertility pie graphs—there is usually one that represents the percentages for all causes of infertility, one that represents the percentages for all female causes of infertility and one that represents the percentages for all male causes of infertility. Take a bite out of these numbers.
For causes of female infertility, the numbers are as follows:
~ 40% of female infertility is due to ovulatory disorder (includes ovulatory dysfunction and diminished ovarian reserve/failure).
~ 30% of female infertility is due to tubal/peritoneal disease.
~ 15% of female infertility is due to endometriosis.
~ 10% of female infertility is unexplained.
~ 5% of female infertility is due to uterine disease/cervical disease.
For causes of male infertility, the numbers are as follows:
~ 35% of male infertility is unexplained.
~ 15% of male infertility is due to varicocele (s).
~ 10% of male infertility is due to hypogonadism (low testosterone).
~ 10% of male infertility is due to urogenital infection.
~ 8% of male infertility is due to an undescended testis.
~ 5% of male infertility is due to sexual dysfunction.
~ 15% of male infertility is due to other causes (immune and systemic diseases).
However, just as there is variability in pie size (give or take a few slivers!) for the percentages of overall infertility diagnosis, the same can be said for female and male causes of infertility. Cutting is most certainly not an exact science!
Additionally, just as no two pies are baked exactly the same, geography matters big time in the pie percentages—it can seriously flavor how big each slice is. For example, in large metropolitan cities where women delay childbirth, you are going to see a much bigger percentage of women experiencing ovarian dysfunction rather than tubal disease. So while percentages and pie slices are helpful, take it with a grain of sugar.