The effects of stress during pregnancy

It is vital to know how stress can affect your and your baby’s health during pregnancy

Pregnancy brings out the worrier (and warrior) in all us ladies.  Celebrating a new pregnancy in the office is such a special moment.  Though soon natural fretting about what to eat, drink, think, feel, and do replace the excitement.  Long term and sustained high levels of stress or poor tolerance of stress has enormous negative mental and physical effects.  We often forget how stressful our lives really are.

Stress affects women during pregnancy just the same as when they are not pregnant

But did you know that it can also have an effect on pregnancy and the unborn baby?  Research shows that a woman who experiences stress during pregnancy may affect her unborn baby as early as 17 weeks after conception, with potentially harmful effects on brain, gut and overall development.

Pregnancy in itself is a stressful time for a woman’s body.  The normal physical and hormonal changes can be quite daunting.  The reality is that excessive and unmanaged stress during pregnancy can have severe consequences for the health of an unborn baby.  It’s already well known that extreme stress during pregnancy can lead to increased risk of miscarriage in early pregnancy.  In the later stages of pregnancy, extreme stress can lead to premature energy, premature birth and low birth-weight babies.  But more than that, the latest findings indicate that prenatal stress can also increase the risk of a baby being born with asthma or allergies and so many other lifelong challenges.

Women with abnormal stress levels, chronic stress or stress that is not handled well are unknowingly exposing their babies to increased levels of cortisol, the stress hormone.  Cortisol levels in the mom can affect birth and baby outcomes in many ways.  For one, the stress hormone cortisol stimulates the production and release of a certain hormone which can lead to preterm birth.  Cortisol in the mother also acts directly on the fetus and its developing nervous system.  Results of some studies have documented that relatively high levels of prenatal maternal cortisol predict:

  • greater behavioural and physiological stress reactivity
  • decreased cognitive ability in infants
  • increased mood problems in young children
  • altered fear and anxiety responses in young girls

How else does stress affect mom and ultimately baby’s health?

During the 1st trimester, stress alters the growth of microbes living in the mother’s vagina.  These are passed on to the baby during birth and are associated with differences in gut microbiome as well as brain development.  In 2013, research presented by the Society of Neuroscience found that “features of the mother’s vaginal microbiome were altered by stress, and in turn, changes were transmitted to the offspring’s gut.”

Increased maternal stress elevates the fetal heart rate

Interesting research comparing stress to mood changes, showed that a bad mood or a bad day does not alter the fetus heart rate, but stressful situations do.

Brain development is strongly affected by maternal stress

Maternal stress changes the normal brain development trajectory, alters brain cellular behaviour, brain structure, disturbs neurotransmission and reprograms the vulnerability or resiliency to neurological diseases later in life.  Research cannot explain what the underlying mechanisms causing these changes are, but some suggest that cortisol plays a critical role in epigenetic programming.  What the heck does that mean?  Epigenetics deals with genes being switched on or off by external factors outside of our underlying DNA sequence.  For example, high cortisol levels from the mom circulating to the fetus cause a change in how the genes are expressed and therefore how the brain/body develops.

Enhanced vulnerability of neonatal hypoxic-ischemic encephalopathy (HIE)

That one is a mouth full, but basically – hypoxic – lack of oxygen, ischemic – restricting blood flow, encephalopathy – affecting the brain.

Studies indicate a close link between stress during pregnancy and enhanced risk of development of cardiometabolic syndrome, stroke, neuro-behavioral, neuropsychological and neuropsychiatric disorders in adolescence and/or adulthood.  However, there is little research showing the potential harmful effects of fetal stress on the susceptibility of neonatal HIE.  Given the impact of prenatal stress on the programming of brain structures and functions as discussed above, it is possible that fetal stress may induce the sensitive characteristics of HIE in the neonatal brain through reprogramming expression patterns of some key functional genes and/or proteins involved in the pathophysiology of HIE.  More research needs to be done in this area.

Chiropractic can help reduce stress during pregnancy

While everyday pressure is a part of modern life, taking care of yourself is an essential part of taking care of your unborn baby.  Pregnancy is characterised by constant change from the moment of conception.  A woman’s body can be supported by gentle chiropractic adjustments to assist with stress resilience, physical tension release and to facilitate a more balanced nervous system.  Cutting down on stress or learning how to manage it is critical to a healthy pregnancy, birth and importantly your baby’s short term and long term health and development.

Research articles: