Here’s a number most of us never look at before buying a phone: its SAR, or specific absorption rate. It tells you how much radiofrequency energy your body absorbs from that phone, measured in watts per kilogram (W/kg). It’s usually buried in the settings menu or the fine print of the manual.
A 2024 study from Turkey looked at that number in a new way. Instead of asking pregnant women only how much they used their phones, researchers also asked which phone they used — and then looked at their babies’ birth size.
Study at a glance
- Title
- Evaluation of neonatal outcomes according to the specific absorption rate values of phones used during pregnancy
- Authors
- Melek Büyükeren, Fikriye Karanfil Yaman
- Journal
- Journal of the Turkish-German Gynecological Association, 2024
- Who
- 1,495 women who gave birth at Konya City Hospital, Turkey (Sept 2020 – Feb 2021)
- Measured
- Phone SAR value and daily phone time during pregnancy vs. newborn outcomes
What the researchers found
“Small for gestational age” means a baby is smaller than expected for how many weeks along the pregnancy was. It matters because SGA babies can face more health challenges after birth.
The key finding: as the SAR of the phone a mother used during pregnancy went up, the likelihood of having an SGA baby went up significantly (p = 0.001). The researchers identified 1.23 W/kg as the SAR value that best separated the two groups.
How well phone SAR separated SGA from non-SGA births
Diagnostic accuracy of the 1.23 W/kg SAR cut-off (higher = better at telling the groups apart)
AUC shown as a percentage for readability (0.685 → 68.5). An AUC of 0.5 would mean no better than a coin flip; 1.0 would be perfect.
View as table
| Measure | Value |
|---|---|
| Sensitivity | 69.3% |
| Specificity | 73.0% |
| Area under the curve (AUC × 100) | 68.5% |
Two other results are just as important to share:
- Daily phone time did not matter in this study. There was no correlation between how many hours a day mothers used their phones and SGA (p = 0.969). The researchers noted that phone use was high across nearly everyone, which made it hard to compare light and heavy users.
- Preterm birth was not linked to either measure. 13.6% of babies were born preterm, and neither SAR nor phone time differed between preterm and full-term births.
What this means for moms
I find this study interesting because it points to something we can actually control. You can’t always cut your screen time in half — but you can look up the SAR of your phone and make choices about how close it sits to your body.
It also reinforces the theme running through this whole series: distance matters. A phone’s SAR describes what’s absorbed when it’s held against the body, so keeping it off your belly and away from your head reduces what you’re actually absorbing, whatever phone you own.
The honest part: This was a retrospective study from a single hospital, which means it looked backward at records and recall rather than following women forward. It shows an association, not proof that phone SAR caused smaller babies. The authors themselves call for prospective studies that look at trimester-by-trimester exposure. I’m sharing it because it’s a thoughtful new angle, not because it closes the case.
Practical steps
- Look up your SAROn most phones it’s in Settings → About / Legal, or on the manufacturer’s site.
- Distance beats durationSpeakerphone and a bag instead of a pocket reduce what you absorb.
- Upgrading?Compare SAR values when you’re choosing your next phone.
- Strong signal, lower outputPhones work harder (and emit more) with weak signal — avoid long calls in dead zones.
Want one simple step for your home? Aires is the EMF protection I use in my own home and for my own kids — and Moms Against EMF readers get 25% off every order.
Sources
- Büyükeren M, Karanfil Yaman F. Evaluation of neonatal outcomes according to the specific absorption rate values of phones used during pregnancy. J Turk Ger Gynecol Assoc. 2024. PMC10921072
This article is an accessible summary of published research for a general audience. It is educational content only and is not medical advice. Please talk with your own healthcare provider about your family’s specific situation.
