The Effects of Stress on Reproduction

In this maelstrom of a world, an expecting mother can easily be swept away by life’s stressors. Pregnancy is an intricate process that can be adversely affected by many factors. Usually, physical factors tend to dominate the physician’s radar when discussing adverse birth outcomes. Psychological factors, however, can have just as large an impact on the vitality of a fetus, but are often overlooked. The mental health of an expectant mother can be a precursor to adverse outcomes such as preterm birth and low birth weight. Simply put, Infants born weighing less than 3.31 lbs. are sixty-five times more likely to die within the first year than infants of normal weight. Furthermore, those surviving, low-birth weight infants are prone to subnormal growth and illness, as well as deficits in cognition, neuromotor function, and attention (Lobel, DeVincent, Kaminer, & Meyer, 2000). The increasing national mental health conversation must be extended to expecting mothers, as our future generations depend on this awareness.

One major aspect of mental health is stress. Stress triggers sympathetic nervous system activation and physiological changes in the hypothalamic-pituitary-adrenal axis (HPA), which increase hormone levels that can stimulate preterm birth. Also, persistent HPA stress reactions lead to increased inflammation and weakening of the immune system, making the body vulnerable to disease and infection. During episodes of long term stress, the HPA axis remains activated, causing excess productions of the hormone cortisol. This influx in cortisol exhausts the stress mechanism and leads to depression and fatigue (“Stress: The Unseen Killer,” 2015). A person’s disposition is a good indicator of how they will react to stress. Exercising during pregnancy is a positive coping method that can be extremely beneficial by reducing the levels of hypothalamic, pituitary, and placental hormones that are associated with lower risks of preterm delivery (Lobel, DeVincent, Kaminer, & Meyer, 2000). Moreover, optimists tend to have good adaptive skills and are able to cope with stress in productive manners because they anticipate positive futures. However, pessimists have low expectations and expect life events to go poorly. The coping mechanisms of optimists and pessimists juxtapose each other. For example, optimists tend to have healthy outlets for stress, such as physical activity, while pessimists are more likely to turn to things such as substance abuse. Therefore, pregnancy-damaging stress can be alleviated with active and positive lifestyles.

As previously stated, preterm birth is significantly affected by social and mental factors. Younger women have the highest chance of preterm birth when exposed to stressful life events prior to conception (PSLEs). A younger woman’s brain is pathophysiologically more vulnerable to the repercussions of stress due to the over activation of stress hormone receptors (Witt, 2014). In fact, in the study “Preterm birth in the United States: The Impact of Stressful Life Events Prior to Conception and Maternal Age”, loss of a parent was the most frequent PSLE for women aged 15 to 19. Such unexpected losses are more traumatic for younger women. While, older women anticipate such events, lessening the pathophysiological effects. Moreover, adolescent mothers tend to be more emotionally and financially reliant on parents or partners than older women. Therefore, the loss of a parent or partner for an adolescent mother may significantly diminish their resources. These traumatic events serve to intensify stressors already present in motherhood and cause anxiety about the kind of future they can provide for their unborn child. Thus, young pregnant women must take additional care to stay mentally healthy.

While PSLEs were associated with increased preterm births in adolescence, other societal issues face pregnant mothers. Within minority groups, large disparities in preterm birth exist. African-American women experience preterm birth at much higher rates than White women. The disparity is thought to be due to the “weathering” effect. Weathering is characterized as premature aging, which has an impact on reproduction as physical consequence of social inequality over the course of life (Witt, 2014). Additionally, a research study on psychosocial factors in relation to race and adverse birth outcomes, found a larger susceptibility in African-American women (Dole, 2004). For example, African-American women facing greater perceived racial and gender discrimination are more likely to experience preterm birth. In contrast, White women are not associated with increased preterm birth due to these factors. In conclusion, perceived discrimination “[induces] different coping responses that in turn are predictors for hypertension” (Dole, 2004). Women who engaged in avoidance coping styles were more likely to experience preterm birth, but the prevalence was higher in African-American women (Dole, 2004). Thus, even difficult social and racial environments had adverse effects on pregnancy.

Yet another social factor has been associated with poor pregnancy outcomes: homelessness. According to Stein and Gelberg, authors of Severity of Homelessness and Adverse Birth Outcomes, “homelessness itself and other factors associated with homelessness may be so debilitating to women of reproductive age that ethnicity may not matter or may matter very little in birth outcomes” (Gelberg & Stein, 2000). For example, homeless women suffer from poor nutrition, lack of psychological support, and insufficient prenatal care. All of these challenges can be harmful to a developing infant. In combination with these issues, many homeless women tend to have extreme substance abuse issues and mental health issues that preceded and facilitated their homelessness. Ultimately, the day-to-day struggles of homelessness are superimposed with the challenges of pregnancy, causing a cycle of destructive stress and depression. In addition, homeless women are less likely to seek out prenatal care due to embarrassment of their financial situation and inaccessibility. Though homelessness is associated with other adverse conditions, homelessness itself is also a factor for adverse birth outcomes and is supported by the weathering hypothesis. Correspondingly, the percentage of one’s life spent homeless correlates directly with adverse birth outcomes, due to the chronic stress homelessness causes (Gelberg & Stein, 200). Therefore, the weathering hypothesis is compellingly supported by the correlation between homelessness severity and poor birth outcomes.

            In order to alleviate the epidemic of stress-induced birth complications, physicians need to be more aware of the correlations between mental and physical health. Adolescents, people who are homeless, and African-American women are some of the most groups affected by stress-related adverse birth outcomes. Prenatal care alone cannot ameliorate the effects of weathering on reproductive health. Preventive prenatal care in a judgement free environment needs to be accessible for all women, as reproductive health prior to pregnancy is as important as during pregnancy when discussing birth outcomes. Moreover, physicians need to be aware of the association between discrimination and preterm birth in African-American women, and devise healthy and productive methods for coping with stress. Healthy methods for coping with stress can serve to improve birth outcomes for all women. In conclusion, promoting healthy lifestyles and positive outlooks on life encourages beneficial behaviors that serve to improve not only the physical and mental health of the mother, but also the child.

 

References

Dole, N., Savitz, D. A., Siega-Riz, A. M., Hertz-Picciotto, I., McMahon, M. J., & Buekens, P. (2004). Psychosocial factors and preterm birth Among African American and White women in central North Carolina. American Journal of Public Health, 94(8), 1358-1365. doi:10.2105/AJPH.94.8.1358

Lobel, M., DeVincent, C. J., Kaminer, A., & Meyer, B. A. (2000). The impact of prenatal maternal stress and optimistic disposition on birth outcomes in medically high-risk women. Health Psychology, 19(6), 544-553. doi:10.1037/0278-6133.19.6.544

Stein, J. A., Lu, M. C., & Gelberg, L. (2000). Severity of homelessness and adverse birth outcomes. Health Psychology, 19(6), 524-534. doi:10.1037/0278-6133.19.6.524 

Stress: The Unseen Killer. (2015). Introduction to Psychology. University of Minnesota Libraries Publishing.  

Witt, W. P., Cheng, E. R., Wisk, L. E., Litzelman, K., Chatterjee, D., Mandell, K., & Wakeel, F. (2014). Preterm birth in the United States: The impact of stressful life events prior to conception and maternal age. American Journal of Public Health, 104(Suppl 1), S73-S80. doi:10.2105/AJPH.2013.301688