Myth #2: “CLMs are getting more common”

It can certainly feel like congenital lung malformations (CLMs) are suddenly everywhere, especially if you’re active on Facebook groups. More people are coming across them, more parents are being diagnosed during pregnancy, and you may even hear people asking, “Why is this happening so much now?”

But here’s the reality:

Fact: They aren’t necessarily becoming more common, we’re just finding them more often.

As far as we know, CLMs are not increasing in the population. What has changed is our ability to detect them early during pregnancy.

Modern prenatal ultrasounds are far more detailed than they were even a decade ago. That means radiologists and maternal-fetal medicine teams can spot lung lesions that previously would have been missed.

So why does it look like there are “more cases”?

Because there are more diagnoses, not necessarily more CLMs.

In the past, many mild CLMs (and remember that the vast majority—90%—of CLM cases are asymptomatic) were:

• never detected at all, especially if a child had no symptoms, or

• found later by chance, for example after a chest X-ray done for recurrent infections like pneumonia (or even something totally unrelated)

Now, 70% of CLMs are identified as part of routine prenatal care. That can be scary, but it can also be helpful. Knowing earlier means your team can monitor growth, watch for signs of complications, and plan for delivery and newborn care if needed.

If you’ve been thinking, “Why are there so many of these now?” you’re not imagining the increase in diagnoses. But the most likely explanation is simple: we’ve just got better at seeing them.

And if you’re newly diagnosed, you’re not alone. Thousands of families are navigating this, and the vast majority of babies with CLMs go on to do very well. Check out our outside resources page or talk to a parent if you’re looking for support or have questions you want answered.