I’m excited to share some fascinating insights from our recent lecture in Paris. My wife, Jody and I had the privilege of speaking at an international intestinal conference. The theme was “Maternal, Placental, Fetal, and Neonatal Microbiomes: Creation and Correction.” We discussed the four maternal microbiomes, their impact on fetal development, and the role of sunlight in this complex interplay.

Jody and I at the stunning Hôtel de Ville in Paris with 2024 Olympics signage!
Here’s a detailed look at the scientifically supported data and some personal stories from our experience.
Understanding the Maternal Microbiomes
During our talk, we delved into the four key maternal microbiomes:
- Intestinal Microbiome: The community of microorganisms living in the intestines.
- Vaginal Microbiome: Microorganisms residing in the vaginal area.
- Blood Microbiome: Microorganisms present in the bloodstream.
- Oral Microbiome: Microorganisms found in the mouth.
These maternal microbiomes influence the development of the placental microbiome, which serves as the connection between the pregnant woman and the growing fetus. Amazingly, the fetal gut begins harboring a mix of beneficial and harmful microbes even before the baby is born.
Disruption and Correction of Microbiomes
Our presentation covered not only the creation but also the correction of these microbiomes. Disruptions can occur due to various factors, including environmental toxins, lack of Nature’s sunlight and adverse childhood events (ACEs) such as divorce, substance abuse, or trauma.
Adverse Childhood Events and Microbiome Health
My wife Jody, a Licensed Clinical Social Worker (LCSW), and an expert in adverse childhood events (ACEs), presented a thought-provoking concept. Since ACES negatively impacts an individual’s microbiome and because disrupted microbiomes can be passed down through generations, the effects of ACEs may begin even before conception and even before conception. Which makes optimizing microbiome health crucial to prevent disrupted microbiomes being passed down from generation to generation. By addressing microbiome health before conception and/or during pregnancy, a huge opportunity to prevent autoimmune and chronic disease exists.

Jody and I on a cool day in Paris in front of the sunlit Pantheon
The Role of Sunlight in Microbiome Health
I had the opportunity to discuss how sunlight exposure influences microbiomes and fetal brain development. Non-image forming, inherently photosensitive retinal ganglion cells in our eyes respond to light and send signals to various brain regions, including:
- The amygdala (involved in emotional processing)
- Areas regulating mood and circadian rhythms (which impact gut microbiomes)
- The hypothalamus (part of the hypothalamus-pituitary-adrenal or HPA axis, which modulates stress responses)
Amazingly, a developing fetus has these special retinal cells by early in the second trimester, even before the image-forming cells (rods and cones) are fully formed. Sunlight exposure during pregnancy supports healthy fetal brain and intestinal microbiome development.
Sunlight, particularly infrared light (most prevalent at sunrise and the first 3 hours), influences the hypothalamus-pituitary-adrenal (HPA) axis, which regulates stress responses. Sunlight hitting the non-image forming retinal ganglion cells projects to brain regions involved in emotions, mood, and circadian rhythms, all of which impact the gut microbiome.
In addition to seeing red light, exposing your abdomen to infrared light can positively influence intestinal microbiomes. This goes for all of us, pregnant or not, early morning sunlight on the belly is great for gut health.

Hanging out with the patron saint of physicians, Saint Pantaleon, at the Cluny Museum of Medieval Art in Paris
Maternal and Fetal HPA Axis Development
Developing a healthy maternal HPA axis during pregnancy is crucial for setting up the fetal HPA axis. Early in the second trimester, the fetus’s eyes develop non-image forming retinal cells, which help in brain development and intestinal microbiome formation. This interaction underscores the importance of sunlight, especially in the first three hours after sunrise, for both the mother and developing fetus.
However, balance is key – dark, nighttime conditions are also essential for circadian rhythms. Blocking harmful blue light, now ubiquitous in our modern world, is also crucial for overall health.
Practical Tips for Optimizing Microbiome Health
- Sunlight Exposure: Aim for exposure during the first three hours after sunrise to maximize infrared benefits. For a deeper dive on the benefits of morning sunlight, checkout my blog on the topic.
- Block Harmful Light: Limit exposure to problematic blue light, which is pervasive in modern environments.
- Balance Light and Dark: Ensure a healthy balance of light exposure and darkness to support circadian rhythms.
Blue Light Blocking Glasses Vendor Recommendation
In researching different vendors for blue light blocking glasses, Spectra479 is one company that several of us on the team are using for adults and kids. They provide testing of their lenses and offer great quality for a reasonable price https://spectra479.com/drbilstrom. Use code DRBILSTROM for 15% of your purchases. It’s important to note that toxic artificial blue light can also get into the body through skin, so covering up while using devices after sundown will also help.
Conclusion
Thank you for joining us in exploring these crucial topics. Let’s continue to optimize our health by understanding and nurturing our microbiomes. For a deeper dive into the benefits of early morning sun and the benefits of blocking artificial light at night, check out this blog.