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PUSH for Empowered Pregnancy
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Measure The Placenta

Behind every healthy baby is a healthy placenta. Though a temporary resident in your body, the placenta is arguably one of the most important organs - without it, pregnancy wouldn't be possible!

Unfortunately, the placenta is also one of the least understood parts of the body. (We're going to go ahead and chalk that one up to the patriarchy! Ugh.)

But never fear - a handful of intrepid scientists are blazing the trail and discovering new insights about this miraculous hunk of mystery every day, including why every doctor should be paying it much closer attention.


THE IMPORTANCE OF MONITORING THE PLACENTA

It has been well documented that there is a clear link between abnormal size of the placenta and adverse pregnancy outcomes. In fact, a small placenta is the most common cause of third trimester stillbirth, and abnormal placenta weight has been found to be associated with conditions ranging from preeclampsia to cerebral palsy to heart defects.


And placenta size isn't the only thing that matters. In fact, placenta size is really more of a "handy shortcut" (in statistics, this is called a "proxy") to measure how efficiently the placenta is operating. Maternal Vascular Malperfusion (MVM) is the technical term to describe problems with how the placenta is passing nutrients between parent and baby; though 50% of pregnancies where MVM is present result in a healthy delivery, the other half are affected by conditions like preeclampsia, fetal growth restriction, and stillbirth. Research is currently underway to help identify which pregnancies are most at risk by measuring the levels of special proteins in the pregnant person's blood - for example, Placenta Growth Factor (PlGF) or other biomarkers - especially when MVM is present. However, more study is needed.


But even despite all this evidence, most doctors don't give the placenta more than a cursory glance during pregnancy. Why?

ONE PROMISING SCREENING TOOL: EPV (ESTIMATED PLACENTAL VOLUME)

Until recently, it was really hard to #MeasureThePlacenta - but that all changed with the advent of Estimated Placental Volume (EPV).


EPV is just one way to monitor your baby's placenta, and there are several other tools available to providers. The benefit of EPV, however, is that unlike techniques that require the use of expensive machinery like MRI or 3D Ultrasound, or need many (sometimes invasive) measurements to calculate, EPV is "quick, cheap, and dirty."


This simple set of measurements can be done in 30 seconds during any routine 2D ultrasound, and will give your healthcare provider an accurate estimate of how the size of your baby's placenta compares to other babies' of the same gestational age (also known as a growth curve). This will allow them to flag if your baby's placenta is unusually small or large, or if there is a mismatch between the size of your baby and their placenta. If there is any cause for concern, your doctor can then order extra monitoring until they determine it is safe to deliver.


Download an informational Measure the Placenta flyer to share with your provider here or order printed copies from our Educational Materials Store!



ISN'T MY DOCTOR ALREADY MONITORING THE PLACENTA?

Your medical provider is likely already charting your baby's growth, but before EPV was created, it wasn't straightforward or cost effective to do this for their placenta. Instead, most doctors today simply observe the location of the placenta within the uterus and note where your baby's umbilical cord attached to the placenta. These are important data points, but are missing a key piece of the puzzle - adding placental volume to the mix gives your doctor a much fuller picture of your baby's wellbeing.

It's important to recognize that babies of any size can have a small placenta; there is a common misconception that if the baby is not concerningly small, the placenta must be fine. Unfortunately, this isn't true - some babies will slow their growth to match the placenta, but (likely due to genetic factors determining their size), others won't. And in time, those babies will actually outgrow their own placenta, like trying to run an 18-wheeler on a compact car engine. The closer these babies get to full term, the more likely their placenta is to reach its limit, tragically resulting in the stillbirth of an otherwise healthy baby.

Sometimes, a baby whose placenta is struggling will show changes in their normal fetal movement (see #MovementsMatter & #KnowYourNormal). But not always. Much like a car running low on fuel will operate normally until it just gives out and the car stops operating without warning, so too will the placenta.


THE BOTTOM LINE

There is solid data on the accuracy of EPV measurements - its effectiveness as a tool to detect small placentas during pregnancy is not in dispute. And we know that small placentas increase the risk of stillbirth. What is not yet demonstrated in published research is this million dollar question: Does measuring the placenta with tools like EPV actually improve pregnancy outcomes in clinical practice? 


It certainly seems likely, but the necessary studies have not yet been completed. Unfortunately, there are major logistical and ethical challenges associated with running a typical study on any stillbirth prevention technique, and that includes EPV, so it may be a while before we have the highest levels of evidence in hand.