Understanding maternal stress, the developing nervous system + supporting yourself through pregnancy
Pregnancy can bring an enormous amount of change. Your body is adapting, your baby is growing rapidly, and somewhere amongst the appointments, scans, work, family life and preparing for what comes next, there can be a lot happening emotionally too.
Most mums have also heard some version of “try not to stress” during pregnancy. It sounds simple enough, but it can leave you wondering what stress actually means for your baby, particularly when life doesn't suddenly become stress-free just because you're pregnant.
Research has explored how a mother's physical and emotional environment during pregnancy may influence aspects of foetal development, including the developing nervous system. But this is a much more nuanced conversation than “stress is bad for your baby”.
Normal, everyday stress is part of being human. Pregnancy doesn't require you to be perfectly calm, and feeling worried, overwhelmed or having a difficult week doesn't mean you've harmed your baby.
So, what do we actually know about stress, pregnancy and the developing nervous system?
Your baby’s nervous system starts developing early
The nervous system is one of the earliest body systems to begin developing during pregnancy.
During the first weeks after conception, structures that eventually form the brain and spinal cord begin taking shape. From there, development continues throughout pregnancy as increasingly complex neural pathways and autonomic functions emerge.
By the time your baby is born, their nervous system has already been through months of extraordinary growth, but development certainly doesn't stop there. The brain and nervous system continue to mature throughout infancy, childhood and beyond.
It can be tempting to describe the nervous system as the body's “master control centre”, but development isn't a simple top-down process where one system controls everything else. The nervous, cardiovascular, endocrine, immune and other body systems develop alongside one another and continually interact.
Pregnancy really is a remarkable example of many systems developing together.
So, can your stress reach your baby?
In a sense, a mother's physiology and the developing baby are closely connected, but not because the umbilical cord acts like an electrical cable carrying stress from one nervous system to another.
The placenta and umbilical cord provide the connection through which oxygen, nutrients and other substances are exchanged between mother and baby. The placenta also plays an important role in hormonal signalling and helps regulate aspects of the foetal environment.
When we're under stress, our bodies can produce physiological responses involving hormones such as cortisol and changes in heart rate, breathing and other systems.
Researchers have therefore investigated whether significant or sustained maternal stress during pregnancy may be associated with differences in pregnancy outcomes and aspects of foetal and child development.
Some associations have been observed, but this area is complex. Genetics, physical health, mental health, social circumstances, nutrition, sleep and many other factors can influence pregnancy and child development.
Stress is one part of a much bigger picture.
This isn't about blaming mums
This point matters. Learning about prenatal stress should never leave a mother feeling that every difficult day, anxious thought or stressful period is somehow being permanently imprinted on her baby.
Pregnancy happens in real life. There are work deadlines, financial pressures, other children to care for, relationship challenges, pregnancy symptoms, health concerns and sometimes circumstances completely outside our control.
Research into prenatal stress looks at patterns and associations across populations. It doesn't allow us to predict an individual child's future based on how stressed their mother felt during pregnancy.
Rather than adding another thing to worry about, this information can remind us that supporting the wellbeing of the mother matters too.
What about the autonomic nervous system?
The autonomic nervous system helps regulate many processes that happen automatically, including heart rate, blood pressure, digestion and responses to changing demands.
During pregnancy, a mother's cardiovascular and autonomic systems undergo substantial adaptations to support both her own body and the developing pregnancy.
The baby's autonomic nervous system is developing too, with patterns of foetal heart rate and heart rate variability changing as pregnancy progresses.
Researchers have explored relationships between maternal physiology, stress and foetal heart-rate patterns. This is an interesting and evolving area of research, but it doesn't mean the mother's and baby's nervous systems are directly “wired together” or that maternal nervous system regulation determines a baby's future health.
Where does HRV fit?
Heart Rate Variability, or HRV, describes the natural variation in timing between consecutive heartbeats. HRV is influenced by the autonomic nervous system and is used in research to explore aspects of autonomic activity and adaptation.
During pregnancy, HRV can be influenced by many things, including breathing, sleep, physical activity, fitness, illness, medications and the normal physiological changes of pregnancy.
Research has also explored maternal and foetal heart-rate patterns. However, a mother's HRV measurement isn't a direct measurement of her baby's nervous system development and cannot tell us whether a baby is developing “optimally”.
At Restore, HRV may be included as one component of our INSiGHT scanning technology. We consider this information alongside your history and chiropractic examination rather than interpreting it as a pregnancy or foetal health test.
It doesn't replace the important information gathered through your regular antenatal care.
Supporting yourself through pregnancy
Rather than aiming for a perfectly “regulated” pregnancy, it can be more helpful to focus on the things that support your overall physical and emotional wellbeing.
That may include prioritising sleep where possible, eating regularly, staying appropriately active, spending time with people who make you feel supported and finding moments throughout the day that allow you to slow down.
For some women, that might be walking, breathing exercises, prenatal movement, time outdoors or simply creating a little more space in an otherwise busy week. And sometimes support needs to go beyond lifestyle strategies.
If anxiety, low mood, overwhelm or stress are becoming difficult to manage, your GP, midwife or obstetric care team can help connect you with appropriate pregnancy and mental health support. You aren't expected to navigate everything on your own.
Where might chiropractic fit during pregnancy?
Pregnancy creates significant physical changes as your body adapts to a growing baby.
Changes in posture, load and movement can contribute to musculoskeletal discomfort for some women, including back or pelvic pain.
At Restore, chiropractic assessment during pregnancy focuses on musculoskeletal concerns relevant to chiropractic care, including joint movement, muscle function and physical tension.
Chiropractic care isn't used to treat maternal stress, regulate your baby's nervous system or influence foetal development. It also doesn't replace antenatal care with your GP, midwife or obstetric team.
Where chiropractic care is clinically appropriate for a musculoskeletal concern, it may form one part of your broader pregnancy healthcare. Australian chiropractic advertising guidance specifically distinguishes musculoskeletal pregnancy complaints, such as back pain, from unsupported claims about treating the unborn child or non-musculoskeletal pregnancy outcomes.
You get to build the support team you need
Pregnancy care isn't only about measurements and appointments. It's also about feeling informed, listened to and supported as your body moves through an enormous period of change.
Your antenatal care plays an essential role in monitoring your health and your baby's development. Alongside that, you may choose to have other practitioners involved depending on your individual needs, such as a physiotherapist, psychologist, dietitian or chiropractor for an appropriate musculoskeletal concern.
There doesn't need to be a competition between different forms of care. The important thing is understanding what each practitioner is there to support, and making choices that feel informed and appropriate for you. And if you're feeling stressed during pregnancy, remember that the goal isn't perfection.
Supporting your own wellbeing matters, but an anxious day isn't a failed day, and your baby's development isn't determined by a single stressful week. Pregnancy is a long, complex process of growth and adaptation, for both of you.
___
Important information: This article provides general educational information only and isn't intended to replace individual antenatal, medical or mental health advice. Chiropractic care during pregnancy is not a substitute for care from your GP, midwife or obstetric team and is not used to assess or treat an unborn baby. If you're concerned about your physical or emotional health during pregnancy, speak with an appropriately qualified healthcare professional.
-
Pregnancy, Birth and Baby (Australian Government). Information and support for emotional wellbeing and mental health during pregnancy.
Dunkel Schetter, C. & Tanner, L. (2012). Anxiety, depression and stress in pregnancy: implications for mothers, children, research, and practice. Current Opinion in Psychiatry.
DiPietro, J. A. (2012). Maternal stress in pregnancy: considerations for fetal development. Journal of Adolescent Health.
Shaffer, F. & Ginsberg, J. P. (2017). An Overview of Heart Rate Variability Metrics and Norms. Frontiers in Public Health.
Australian Health Practitioner Regulation Agency (AHPRA) & Chiropractic Board of Australia. Check your advertising: Chiropractic examples.
Original Article: Adapted from Why Your Stress Reaches Your Baby Before Birth, originally published by PX Docs.