Birth Small Talk

Talking about birth

New horizons for fetal monitoring: Photoacoustic assessment of the fetal brain and placenta

Photo by Rohan Makhecha on Unsplash

There is increasing recognition that CTG monitoring hasn’t delivered on its promise to accurately identify the fetus who would benefit from early birth, and therefore has failed to improve perinatal outcomes. This has opened a space for researchers to begin to investigate novel approaches that might prove to be a better tool than the CTG. One of these novel technologies is photo-acoustic assessment.

Kang and colleagues from Johns Hopkins, Baltimore, USA provided a recent summary of this technology, including an explanation of the physics of how it works (which I will leave to them as it is complex!). The approach aims to be non-invasive and generate real-time information about the level of oxygen in tissues, specifically the fetal brain and placenta. To date, most of the research has been done on animals, showing high levels of accuracy for detecting both low and normal oxygen levels.

There appears to be still quite a way to go before photoacoustic assessment would be ready for clinical practice. It is my fervent wish that researchers learn from the mistakes made in the introduction of CTG monitoring into practice without adequate assessment. Having sound evidence of the short- and long-term benefits of any new approaches is required before we begin to invest in such technology. 


Kang, J., Koehler, R. C., Graham, E. M., & Boctor, E. M. (2021, Oct 15). Photoacoustic assessment of the fetal brain and placenta as a method of non-invasive antepartum and intrapartum monitoring. Experimental Neurology, 347, 113898.

Categories: New research, Perinatal brain injury


2 replies


  1. Adding something extra to make the CTG work – Birth Small Talk
  2. What are the gaps in our knowledge? – Birth Small Talk

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s