Gene mutations in men and obscure viruses in women can cause infertility. Here’s a basic list of the most commonly known reasons men and women can’t get pregnant, plus four research studies that describe lesser known causes of male and female fertility problems.
If you’ve been trying to get pregnant for more than a year, you may be wondering about the signs of male and female infertility. I can’t tell you if you’re infertile, but I have gathered a list of 20 possible causes of infertility – one of which may be stopping you from conceiving a baby. Because this article is so popular, I also added four scientific research-based reasons men and women can’t get pregnant.
An important thing to remember about whose “fault” it is if you can’t get pregnant: “In about 40% of the cases [of infertility], the problem resides in the woman, and in 40%, the problem is in the man’s reproductive system,” says obstetrician, gynecologist, and fertility expert Robert Thompson, MD. “The rest of the time there may be a problem with both the man and the woman.” (alive magazine, February, 2009). The most common causes of infertility are equally male and female based. So, if you’re searching for reasons you can’t get pregnant, makes sure you look at both the man and the woman.
If you can’t get pregnant, spend some time exploring various university and hospital-based resources and websites about health and fertility issues. Try to avoid personal blogs, because one person’s experience with infertility isn’t representative of an entire population.
And, don’t let your reading cause you to feel anxious or stressed! I know you want to get pregnant and you’re eager to start your family. But, if you succumb to anxiety and fear, you will only make it more difficult and stressful to get pregnant.
Here are a variety of possible causes of infertility for men and women…
Commonly Reported Causes of Infertility for Women
- Age – fertility decreases after age 30, decreases more after 35, and practically plummets after age 40.
- Underweight or overweight – women with Body Mass Indexes (BMIs) over 30 and under 20 are less likely to get pregnant. Ideal BMI is between 20 and 30.
- Hormonal changes – some health problems cause hormonal changes, which can cause decreased fertility or infertility.
- Miscarriages – the more miscarriages a woman has, the less likely she may be to get pregnant
- Sexually transmitted diseases – can affect a woman’s reproductive system.
- Fibroids or endometriosis – depending on how advanced the disease is.
- Pelvic inflammatory disease – can cause problems for women who can’t get pregnant.
The only reliable way to determine if you are affected by one of the above causes of infertility is to make an appointment with a gynecologist. Get tested for whatever the doctor thinks might be the problem. Be upfront and honest about the health issues you’re dealing with now and in the past.
And, as difficult as it may be, try not to get anxious when you read through these causes of infertility for women. Don’t assume you have one of these health issues, just because you can’t get pregnant! Trust that whatever is causing fertility problems is temporary, and you WILL find ways to heal or work around the issues.
Keep the faith.
Research-based causes of female fertility problems
Female infertility affects approximately 6% of 15-44 year old women or 1.5 million women in the United States. Approximately 25% of female infertility cases have no explanation or cause, which doesn’t leave women (and men) with many options for getting pregnant…other than expensive and often disappointing fertility treatments.
An uncommon virus found in women with unexplained infertility
The HHV-6 Foundation found a virus that doctors weren’t well aware of, which may contribute to unexplained infertility in women. This little-known member of the human herpesvirus family is called HHV-6A, and it infects the lining of the uterus in 43% of women with unexplained infertility. Since this virus isn’t found in fertile women, researchers believe it may be linked to problems with fertility and getting pregnant. This study also reported that the infection is exacerbated by hormone estradiol, which fluctuates with the menstrual cycle. High levels of the hormone estradiol may trigger an active infection in the uterus, and causing fertility problems in women.
“This is a surprising and potentially important discovery,” said Dr Anthony Komaroff, a professor at Harvard Medical School who has also researched the HHV-6 virus “If confirmed, the finding may lead to treatments that improve the outcome for a large subset of infertile women.”
The study also found that the response of the woman’s immune system may contribute to making the uterus less hospitable to a fertilized egg. The virus seems to activate immune cells called “natural killer cells” in the uterus; they are triggered to produce chemicals called cytokines. Cytokines are tools the immune system uses to orchestrate an attack on a foreign invader, like a virus.
To learn more about this cause of infertility in women, read Presence of HHV-6A in Endometrial Epithelial Cells from Women with Primary Unexplained Infertility.
Polycystic ovary syndrome as a cause of infertility in women
I was surprised to learn that polycystic ovary syndrome (PCOS) is the most common cause of female fertility problems.
PCOS is a serious metabolic disorder that occurs when your body produces slightly higher than normal amounts of testosterone and other androgens (which are sex hormones associated with male traits). The resulting imbalance of hormones causes irregular or absent periods, weight gain, acne, excess hair, or even thinning hair on the scalp. Up to 5 million women in the United States have PCOS, according to the U.S. Department of Health and Human Services’ Office of Women’s Health.
Past research has linked polycystic ovary syndrome (PCOS) as a reason women can’t get pregnant, but new studies show that weight loss and exercise can improve fertility. A study from The Endocrine Society found that women with polycystic ovary syndrome who underwent “lifestyle modifications” (increased exercise and weight loss) were more likely to get pregnant than women who just took birth control pills to regulate their hormones.
This study was called “Clinical trial compares preconception treatments for common cause of infertility”, but it’s no longer available online. To learn more, read Polycystic Ovary Syndrome (PCOS) and Pregnancy.
Common Causes of Infertility for Men
- Age – but a woman’s age affects her ability to get pregnant more than a man’s age.
- Warm temperatures for testes – laptop computers and “tighty whities” (close fitting underwear) can affect sperm production, motility, and count.
- Prescription medications – can affect sperm and prevent pregnancy.
- Testicular abnormalities – such as varicocoeles can damage or eliminate sperm
If you can’t get your wife pregnant, read 5 Foods That Improve Sperm Count, Health, and Motility.
Research-based causes of male infertility
Again, try not to get anxious when you read through these scientific reasons you can’t get your wife pregnant. The chances aren’t high that you have one of these health issues that cause infertility in men.
X-linked gene mutations cause male fertility problems
According to the University of Pittsburgh, some cases of male infertility are due to mutations in the maternal X chromosome. This genetic mutation prevents development of viable sperm, which can prevent pregnancy. These researchers found that nearly 50% of cases of male infertility that weren’t caused by a physical obstruction have genetic roots. About 20% of infertile men have azoospermia, meaning they don’t make sperm.
“This research suggests screening for TEX11 gene mutations might be useful in cases of otherwise unexplained azoospermia,” says Alexander Yatsenko, M.D., Ph.D., assistant professor of obstetrics, gynecology and reproductive medicine, Pitt School of Medicine, and an MWRI investigator. “It might be possible to one day correct these problems with gene therapy and other interventions. More work must be done to identify other genetic causes of male infertility.”
To learn more, read X-linked gene mutations cause some cases of male infertility on the University of Pittsburgh’s website.
High sperm DNA damage causes unexplained infertility in men
Sperm health research from Queen’s University in Belfast found that 80% of couples who can’t get pregnant because of “unexplained infertility” actually have a reason for not conceiving. That reason is high sperm DNA damage. This new research study is the first of its kind, and might lead to better fertility treatments for men and women who can’t get pregnant.
“The majority of couples experiencing problems with fertility are able to receive an explanation for their infertility,” said Professor Sheena Lewis from the School of Medicine, Dentistry and Biomedical Sciences at Queen’s. “These causes range from low sperm count and poor sperm motility in the man to blocked fallopian tubes or endometriosis in the woman. Once the causes for infertility have been established, the appropriate course of assisted conception treatment can be undertaken.”
Dr Lewis added that almost 30% of couples do not have a reason or cause for infertility. They’re often given the diagnosis of unexplained fertility, and they invest a lot of time and money in fertility treatments (such as intrauterine insemination or in vitro fertilization). “In our study we have now had a breakthrough which explains the cause of infertility for many of those couples,” she said. “Now that we have found the cause of infertility for these couples (high sperm DNA damage), suitable treatments can be tailored for them which will direct them straight to the best treatment and increase their chances of having a baby.”
This article was called High sperm DNA damage a leading cause of “unexplained infertility”, but it’s no longer available in Reproductive Biomedicine Online.
Causes of Infertility for Both Men and Women
- Environmental toxins – pesticides, lead, and even common household cleansers can contribute to problems getting pregnant.
- Career stress – can lead to physical and emotional problems getting pregnant.
- Recreational drug use
- Poor diet, no exercise
- Radiation treatments for cancer
- Smoking – does not increase fertility and can be a cause of infertility for men and women
If you’ve been wondering why you can’t get pregnant and some of the above causes of infertility are familiar to you, talk to your doctor as soon as possible. Fixing possible obstacles to pregnancy and getting pregnant can take months or years…so you want to deal with potential problems right away!
If you can’t get pregnant and you’ve been trying for over a year, read 5 Signs You Should See a Fertility Doctor.
I welcome your thoughts on these causes of infertility in men and women – but I can’t offer advice or medical counseling. If you can’t get your wife pregnant – or if you can’t get pregnant – you need to make an appointment with your family doctor or a fertility specialist.
Don’t rely on the internet for personal medical advice. The internet is a great place to get general information – such as research or scientific-based causes of infertility and reasons couples can’t get pregnant – but it is no place for personal medical health advice.
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