How Stress May Affect Fertility and Pregnancy

In this post, Ariana Golub discusses the potential impact of stress during preconception and pregnancy.

Stress, in a nutshell…

Stress impacts everyone, both negatively and positively. In fact, although we typically think of stress as a bad thing, it’s actually helpful in certain situations (1). However, I’m not here to talk about the positive effects. It’s actually quite the opposite. My focus is on how stress can impact fertility and pregnancy! In fact, recent research shows that it may reduce fertility in both males and females. What’s more, it can have lasting effects on both maternal and child health.

It’s important to understand that stress isn’t just mental and emotional. Your body may be stressed despite your not experiencing depression, anxiety, lack of energy or other overt signs. Basically, anything that places a demand on the body can be considered a stressor! I will go over the major stressors that we are exposed to frequently later on.

Your Roadmap to Learning

Before I dive into fertility and pregnancy, I’ll provide an overview of what stress is and how it works in your body. Then I will review the common stressors in our lives. After that, we’ll jump into how these different stressors may influence our ability to conceive and have a healthy, successful pregnancy. I will finish off with a few recommendations to help you lower your stress so that you optimize fertility and enjoy a successful pregnancy.

Stress from a Biochemical Standpoint

First and foremost, what is stress? There are many definitions out there. However, I appreciate Hans Selye’s studies of the effects of stress on the body: “Stress is the non-specific response of the body to any demand for change.” Clearly, the definition itself is very broad and clearly shows that anything that throws the body out of balance (i.e., homeostasis) can be considered a stressor. The definition also reminds us that stress can be adaptive. In other words, despite what we usually think, it can be beneficial to us. Thus it isn’t inherently bad. Instead, it is the amount of stress and our body’s ability to handle it that are important.

But how exactly does it work in our bodies? In the presence of mental, emotional, physical, or biochemical stressors, the body triggers a dual chain reaction involving the autonomic nervous system (i.e., the one we don’t control!) and the Hypothalamic Pituitary Adrenal (HPA) Axis. These two systems both act directly upon the adrenal glands (2).

The Adrenal Glands

The adrenal glands sit on top of our kidneys and produce hormones responsible for handling all types of stress. These hormones include adrenaline, noradrenaline, and cortisol. The adrenals release stress hormones in response to an actual or perceived threatening situation (think: saber tooth tiger). This, in turn, initiates the fight or flight response, which leads to an increase in heart rate, blood pressure, breathing, and vascular supply to our heart and muscles. During the stress response, the body also releases stored fats and glucose (i.e., sugar) for an energy boost so that we can either “fight” or “flight” (think: run like hell from said saber tooth tiger). Adrenaline/noradrenaline are cleared from the body quickly, whereas cortisol tends to take a longer time. And since cortisol plays a role in other functions in our body, chronic cortisol output as a result of chronic stress can negatively impact these other functions (2).

For instance, when we are in “fight or flight,” the body turns down non-essential functions like digestion and sex hormone production. This is because cortisol is our survival hormone. Why would we need these non-essential life functions if we are running from a saber tooth tiger? But, last I checked, saber tooth tigers – which weren’t a constant issue – aren’t our problem. Instead, it is the chronic stress from our overcomplicated, over-scheduled lives that contributes to the chronic stress we experience and, ultimately, the chronic output of cortisol that negatively affects our bodies.

Types of Stress In Our Current Context

Usually, when we hear stress, we think of “mental stress.” The stress we feel when our responsibilities are overwhelming us; when we have too much to do and too little time to do it in. However, stress comes in many different forms. Here are the stressors impacting our lives on a daily basis:

Poor Diet – when one eats highly processed foods, trans fats, rancid fats, overeats on a constant basis or consumes empty calories, digestion is almost always impacted. A poor diet can lead to difficulty digesting and, thus, inadequate nutrient uptake. Inadequate nutrients mean our body will always be trying to catch up and compensate. Also, digestive dysfunction can lead to food sensitivities, which can keep the immune system revved up and thus result in chronically elevated cortisol levels. Food sensitivities are a huge potential contributor to adrenal stress.
Lifestyle – this includes lack of life balance (i.e., working too much, playing too little, exercising too much or too little), an indulgent lifestyle (i.e., constantly indulging in food, alcohol, and/or drugs), inadequate sleep/rest, and living in front of our screens (TV, mobile, computers, etc.).
Mental Stressors – this is the type that we typically think of when we hear “stress,” and that includes work overload, keeping late hours, sleep deprivation, financial worries, an unfulfilling life, and even negative thoughts/mindset. The way we see our world impacts our physiology, and a negative outlook can keep our stress hormones firing constantly.
Emotional Stressors – things like unfulfilling relationships, death of a loved one, disempowering emotions, not feeling heard, loneliness, divorce, and not having fun!
Physical Stressors – trauma, exercise that is too frequent, too intense, too long for our body; illness, hidden viral/bacterial/parasitic infections; accidents, whiplash; surgery; chronic pain…
Biochemical Stressors – internally produced stressors typically in response to external stressors. These include factors such as blood sugar imbalances, liver overload, gut dysbiosis, infections, xenobiotics, allergies, mold, and inflammation!

Clearly, stress takes on many forms, which, alone or in combination, can impact both fertility and pregnancy.

What Role Does Stress Play in Fertility?

Anything that negatively affects our hormones can potentially decrease fertility and the likelihood of a successful pregnancy. As mentioned above, chronic stress leads to chronic cortisol output. Too much cortisol can lead to insulin resistance which can contribute to excess weight. Excess weight may disrupt the female menstrual cycle, potentially contributing to infertility. Insulin resistance is also connected to an increasingly common female hormone imbalance, Polycystic Ovarian Syndrome (PCOS). PCOS is among the top contributors to infertility today.

One study found that stress reduced the probability of conception as measured by alpha-amylase, a biomarker of stress, in women (3). Both home and work stress are associated with a prolonged time trying to conceive (i.e., more than 12 months), and that cumulative stress from all areas of life may impact fertility. Studies also show that early life stress in women had long-standing effects on health, including fertility. (5). These stressors contribute to dysfunction of the hypothalamic-pituitary-adrenal (HPA) axis and chronic inflammation, impacting fertility and even response to fertility treatments.

The Role of ART

Speaking of fertility treatments, even assisted reproductive treatments (ART) deserve inclusion in this discussion. It’s easy to understand how stressful infertility can be. One paper investigated whether this stress may impact ART outcomes. Since it is difficult to measure stress levels based on self-reports, the paper instead looked at the efficacy of psychological interventions on stress levels. Several studies reveal that these interventions do, in fact, help lower stress and anxiety while simultaneously increasing pregnancy rates (6).

Another study regarding IVF treatments also measured cortisol levels in saliva and hair. Salivary measures indicate short-term cortisol, and hair levels reflect longer-term cortisol in the body. There wasn’t much of an association between salivary levels of cortisol and pregnancy outcomes. However, there was an association between hair sample levels and pregnancy. This suggests that long-term stress might impact the success of IVF (7).

Stress and Male Fertility

But stress doesn’t just negatively impact female fertility. In another study, perceived stress and stressful life events were associated with semen quality in men, and we need high-quality semen for successful conception (8).

Oxidative stress

One form of biochemical stress is oxidative stress, which is the result of free radicals. Free radicals are molecules with unpaired electrons. Those unpaired electrons run around the body in search of another electron. During this process, free radicals can damage hormone receptors and ultimately damage an entire cell. Typically, the body can handle the effects of some free radicals. However, this becomes unsustainable when there is an onslaught of free radicals due to things like poor diet, GI dysfunction, food sensitivities, and inflammation. When there is an imbalance between the renegade radicals and our body’s ability to counter their damaging effects, oxidative stress is the result (9, 10)!

Oxidative Stress and Sperm Health

All of this biochemistry talk is important because the chemical makeup of sperm makes them very susceptible to oxidative stress! In fact, this study found that oxidative stress in males can cause DNA fragmentation of sperm which is an indicator of male infertility and can impact both natural conception and the potential outcome of assisted reproductive treatments (11). What are some contributors to oxidative stress? Intake of vegetable oils (ex: canola oil), lack of antioxidants in the diet, environmental toxins which can contribute to biochemical stress, and even psychological stress (9).

What Role Does Stress Play in Pregnancy?

Although there are more ways than one to measure stress, cortisol is a solid marker of maternal stress. So how might stress affect pregnancy outcomes?

Well, one research team found that higher maternal cortisol levels were associated with an increased chance of early pregnancy loss, mostly in the period before a woman typically knows she’s pregnant (12)! This is huge, particularly for couples actively trying to conceive. The authors of this study pointed out that cortisol rises in response to energetic, psychosocial, and immunological challenges and so heightened cortisol may be a cue for the body that current conditions are not suitable for sustaining the pregnancy. Cortisol also has an antagonistic relationship with progesterone levels. In other words, when cortisol is high, progesterone levels are low. In early pregnancy, sufficient progesterone levels are needed to support the maturation of the endometrial lining so that the fertilized egg can attach and continue to develop! With chronically elevated cortisol, the risk of low progesterone may lead to a higher chance of miscarriage early in pregnancy.

Impact on the developing baby

What about the impact on the fetus during pregnancy? Mental and emotional stress are risk factors for adverse outcomes for both mothers and their babies, including preterm birth. Mom passes along nutrients to her growing child but also hormones like cortisol! Prolonged stress throughout the duration of pregnancy can lead to elevated levels of cortisol in the amniotic fluid, which can influence the growth of the fetus. This may be okay and is actually somewhat of a survival mechanism for the fetus. However, it can impact the maturation of certain organs of the fetus, which can contribute to development issues after birth (13). Psychological distress during pregnancy can potentially lead to preterm labor, and studies demonstrate that women who perceive their lives as stressful have an increased risk for preterm birth and low birth weight (14).

Implications for Early Childhood

Perceived stress and pregnancy anxiety aren’t only predictive of pregnancy outcomes but also of behavior and temperament in the children after they are born. Studies show that babies born to mothers with high cortisol levels were fussier and cried more during early life (15). This in itself can impact the mother’s well-being. In fact, who can deny that fussy newborns can take a toll in and of themselves? Significantly, researchers note that the impact of stress and anxiety in pregnancy can persist through toddlerhood (16). So, in short, prenatal stress can result in early pregnancy loss, preterm birth, low birth weight, and adverse behavior from early life through toddlerhood. And these aren’t even all of the possible implications of maternal stress during pregnancy! There are so many studies on the subject it would be hard to cover each and every finding!

How Can We Reduce Stress so as to Improve Fertility and Pregnancy Outcomes?

Whether you are just beginning your conception journey, have been on it for a while, or are pregnant now, it’s clear that minimizing the various stressors in our lives will provide the biggest benefit to both yourself and if you’re a woman, your growing baby. Here are some things you can focus on now to lower and/or better manage stress:

Optimize your diet and digestion – it’s more important than we realize! Our diet provides the building blocks for our hormones and cells! Without a nutrient-dense diet that includes all of the macronutrients – fats, proteins, and carbohydrates – we may leave our body depleted. We also need to ensure adequate digestive function. This ensures the efficient breakdown of the food we eat, as well as good absorption of nutrients within the food.
Support your liver function – our liver is our main detoxifying organ! It helps clear our system of toxins and excess hormones! We need to be sure we are supporting its function through diet and lifestyle.
Limit external stressors and engage in activities that are restorative – this is obvious but a must! Whether you are trying to conceive or are pregnant already, it is imperative that you limit stress! And if fully removing stressors isn’t possible, make sure you engage in stress-reducing and relieving activities. Don’t forget to include extra sleep and rest! This is the time in your life to send a deep message of safety to your body!
Reduce your toxic exposure – we experience these on a daily basis! They come from the air we breathe, our home and work environments, and the products we use. We can’t live a completely non-toxic life, of course. So the goal is to reduce the burden as much as possible. Take a look at your household cleaning items and personal care products. Consider making the switch to eco-friendly and organic brands. Are you purchasing BPA-free plastic? Great! Even greater is switching to stainless steel and glass! What kinds of pots and pans are you using? Non-stick cookware uses a chemical that leaches into our food during the cooking process and, ultimately, into us. Figure out what exposures you can reduce immediately to limit the impact on your body!

References

About Ariana Golub

Ariana Golub is a Certified Nutritional Therapy Consultant and Restorative Wellness Practitioner. Ariana focuses on supporting women and couples in creating healthy and thriving families through diet and lifestyle support. More information can be found here.