Red light therapy (RLT) is a non-invasive treatment that uses specific low-level wavelengths of light, typically red and near-infrared, to stimulate biological processes in the body. People often use RLT to support skin health, reduce minor aches and pains, and promote muscle recovery. As a widely accessible, non-drug-based option, RLT’s potential benefits lead many expectant individuals to question its safety during pregnancy.
Understanding How Red Light Therapy Interacts with the Body
Red light therapy works through a process called photobiomodulation, where non-thermal light photons penetrate the skin and are absorbed by the mitochondria. Specifically, the light is absorbed by an enzyme called cytochrome c oxidase, a component of the mitochondrial respiratory chain. This interaction accelerates electron transport, enhancing the production of adenosine triphosphate (ATP), the primary energy currency of the cell.
The resulting boost in cellular energy can support various functions, including cellular repair, regeneration, and reduced inflammation. Red light wavelengths (630–660 nanometers) primarily affect surface tissues, while near-infrared light (810–850 nm) penetrates deeper into muscle and bone. Because RLT stimulates increased cellular activity and energy production, the potential impact of this heightened activity on a rapidly developing fetus is the central point of caution for medical professionals.
Current Safety Recommendations and Data Gaps
The medical consensus on using red light therapy during pregnancy is one of caution, primarily due to a lack of sufficient clinical safety data. Ethical constraints prevent researchers from conducting large-scale randomized controlled trials on pregnant women, meaning a definitive safety profile for RLT does not exist. Without robust data, healthcare providers follow the precautionary principle, advising against use in areas that could affect the fetus.
The U.S. Food and Drug Administration (FDA) classifies most RLT devices as low- to moderate-risk Class II medical devices. These devices are “cleared” for general use, not “approved” specifically for pregnancy. This clearance confirms the device is safe for its intended non-pregnancy-related use but does not account for fetal safety. Therefore, the absence of evidence showing direct harm is not the same as having evidence that proves RLT is entirely safe for a developing pregnancy.
Dermatologists and obstetricians advise pregnant patients to avoid the treatment or seek consultation before starting any regimen. While some smaller studies have analyzed laser therapy during pregnancy with no reported risk, these findings are not considered conclusive enough to establish a universal green light for RLT. Any decision to use RLT must be made on a case-by-case basis with an experienced healthcare provider.
Navigating Treatment Areas During Pregnancy
Practical guidance focuses heavily on avoiding certain anatomical regions to minimize any theoretical risk to the pregnancy. Areas that must be avoided entirely include:
- The abdomen, the pelvic region, and the lower back, particularly when using deeper-penetrating near-infrared wavelengths.
- The breasts, especially if the individual plans to breastfeed, due to theoretical concerns about the effect on milk-producing ducts and hormones like prolactin.
Localized treatments far from the core, such as RLT for facial concerns like acne or minor pain in the hands or feet, are possible. Low-level red light (630–660 nm) on non-abdominal areas is suggested as a safer approach than near-infrared light due to its more superficial penetration. However, even for these localized applications, individuals must use devices that do not generate excessive heat, as hyperthermia is a known risk factor during pregnancy.
Full-body RLT beds and prolonged treatment sessions are discouraged, as they increase the potential for systemic absorption and could raise the body’s core temperature. Expectant individuals should limit sessions to short durations (usually 5 to 10 minutes per area) and use only reputable devices. The consensus is that any use of red light therapy, even localized treatment, should only proceed after a thorough consultation with an obstetrician or primary care provider familiar with the individual’s prenatal care.