Key takeaways:
~ About 12% of women in the U.S. experience fertility challenges, with that rate increasing to 25% in women over 30.
~ Genetic variants can influence many factors associated with infertility, such as hormone levels, ovarian health, and the likelihood of structural or autoimmune issues.
~ Understanding your relevant genetic variants can provide insight into possible solutions for your root cause of infertility.
Infertility: Hereditary Causes
According to the CDC, estimates show 12% of US women have impaired fertility. For women over age 30, that number rises to 25%![ref][ref]
Some of the causes of infertility for women can be categorized as follows:
- Hormonal issues: thyroid problems, PCOS, HPA axis dysregulation, reproductive hormone dysregulation
- Structural issues: fibroids, blocked fallopian tubes, other structural abnormalities
- Ovarian insufficiency or premature menopause
- Recurrent miscarriages and more
This article highlights some of the common genetic variants that may play a role in infertility. It is just a starting point… My hope is that it gives you enough information to get started on figuring out the root cause of your problems when trying to conceive.
A quick crash course in reproduction:
A lot of people think of pregnancy in basic terms: sperm meets egg, and 9 months later you have a baby. Birds do it, bees do it. Heck, even trees do it in their own way.
But when you get down to the specific details, it gets a lot more complicated…
Ovarian follicles:
At puberty, women have around 300,000 to 400,000 follicles in their ovaries. These primordial follicles are tiny fluid-filled sacs that contain the oocyte (immature egg cell). Over the course of a woman’s reproductive years, only 400 – 500 eggs will reach maturity.
Hormones stimulate the development of some of the follicles each month. Usually only one will reach maturity each month, at which point ovulation occurs. (The other follicles are broken down and reabsorbed.)
That egg cell that gets released at ovulation is what can get fertilized by the sperm, resulting in a pregnancy if all goes well. The egg needs to be healthy with no DNA damage.
Reproductive hormone levels:
For all of this to happen, the reproductive hormones need to be at the right levels and at the right time. Follicle-stimulating hormone (FSH) rises at the right time to stimulate the immature follicles to begin to mature. Without FSH, the immature follicles will go through apoptosis (cell death).
When the follicle reaches a certain size, it will start secreting estrogen. This causes a surge in gonadotrophin-releasing hormone (GnRH).
The surge in GnRH causes a surge in luteinizing hormone (LH) secretion, which triggers ovulation.
Decreased fertility as we age:
As women age, they have fewer follicles in their ovaries, eventually reaching the end of the reproductive span at menopause. A hormone called AMH (anti-mullerian hormone) is often used as a marker of ‘ovarian reserve’, an estimate of available eggs.
But the ovaries aren’t like a gumball machine, spitting out good gumballs (eggs) up until the last one comes out. Oxidative damage, insults to the cells, etc. cause egg quality to decline as we age.
Conditions that can decrease fertility rates include PCOS (polycystic ovarian syndrome), hypothyroidism, diabetes, and autoimmune diseases.
The risk of recurrent miscarriages also increases with age. Blood clots can increase the risk of recurrent miscarriages, and several genetic variants cause increased clotting.
We will dive into how your genes specifically interact with possible causes of infertility in the Genotype Report section…
Fertility Genotype Report:
Lifehacks: Natural solutions when TTC
I’ve thrown a lot of information into this article, but it is just a portion of what goes into the mix for fertility.
If you are dealing with infertility, genetic variants are probably playing a role — whether through PCOS, altering your vitamin or hormone levels, or increasing risk of problems from toxins. But this is just a part of the picture… stress, sleep, and diet are all important also.
Getting help:
Obviously, the first place to go for help when trying to conceive is your OB/GYN for testing. Your OB can do ultrasounds and other tests to rule out a physical cause. Hormone testing is also available to make sure everything is normal there.
If you are looking for a professional who is familiar with Genetic Lifehacks reports, check out the list of PRO members.
Optimizing fertility:
Your overall health impacts your ability to reproduce. This makes sense for all animals and especially for humans.
There are quite a few genetic variants affecting the very basic aspects of health that also affect fertility. You need healthy egg cells in order to get pregnant. This list is a bit of a hodge-podge of some of those variants that affect the quality of the oocyte.[ref]
Melatonin genes that impact fertility:
Whether you carry the melatonin receptor variant (above) or not, melatonin is important for everyone when it comes to fertility. This is especially true for older women who are TTC – melatonin levels drop as we get older.
The ‘sleep hormone’ does a lot in the body. Within cells, it acts as a natural antioxidant, reducing reactive oxygen species. Melatonin receptors are found in high levels in the ovaries and in the follicle cells. Melatonin turns out to be fairly important in egg quality for IVF.[ref][ref][ref][ref] Melatonin also may play a role in keeping the mother’s body from rejecting the fetus.[ref]
How can you increase melatonin? Two free things you can do that will greatly impact melatonin levels: Block 100% of blue light at night and get out in the sunshine during the day.
Related article: Key to health: melatonin
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BPA, a chemical found in some plastics, has been linked to a variety of effects on people including obesity, insulin resistance, and epigenetic effects on the fetus. It is everywhere in our food supply. In fact, a CDC report showed that 92% of people have BPA in their urine.
Detoxifying Phthalates: Genes and Diet
Plastics are everywhere – and a source of the chemicals that we are exposed to on a daily basis. One component of plastics is a class of compounds referred to as phthalates, which can act as an endocrine disruptor and mimic estrogen.
PCOS: Genetics and Root Causes
Polycystic ovarian syndrome (PCOS) is an endocrine disorder causing an increase in androgen hormone production in women. It also increases the risk of infertility. PCOS affects 5 -10% of premenopausal women, and genetics plays a large role in whether you have PCOS.
BCO1 Gene: Converting Beta-Carotene to Vitamin A
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