More scans. More inductions. More surgery. No benefits.
While sitting in the chair getting my hair done, the stylist and I got to talking about life as women. Relationships with parents, children, partners, and sadly, pregnancy loss. Stillbirth in particular – that terrible sisterhood none of us wants to belong to.
Her precious daughter passed away in utero, full term, just after a late-pregnancy scan that showed everything was fine and baby was well.
The loss was attributed to a cord mishap, probably because there was little evidence of anything else that could have contributed to the baby’s passing.
Some of you may link the ultrasound itself to the pregnancy loss, although the general consensus within the medical industry is that ultrasound has no negative effects on the baby and only provides diagnostic benefits.
However, studies show time and again that when used routinely in late pregnancy, (not because of any developing medical issue) ultrasound scans not only have no benefit but instead contribute to increased harm to mothers and babies. Perhaps I should rephrase that to say, it has no benefit to the mother or baby. It may, indeed, benefit the practice of medicine and its players.
The late pregnancy ultrasound is used primarily to detect foetal size, at which it’s notoriously inaccurate particularly with large babies, amniotic fluid volume with moderate accuracy, and foetal position, for which it’s quite accurate but still does not eliminate the incidence of undiagnosed breech at delivery. The incidence of foetal anomalies first detected at a 35–37-week scan is 0.5%, while the incidence of anomalies first detected at birth is 0.1%.
Ultrasound can provide information to guide clinical decision-making however, it has significant limitations. Using this information as a basis for earlier intervention “just in case” is increasing iatrogenic harm without the hoped-for improvements in outcomes.
Adding to the body of evidence that routine 3rd trimester ultrasounds don’t confer any benefit to the mother or baby is this month’s study Impact of a Routine Third Trimester Ultrasound Policy on Obstetric, Neonatal and Service Delivery Outcomes in an Australian Tertiary Centre (Kumar et al., 2026) whose conclusions state “The benefits of implementing routine third trimester scans in ‘real-world’ clinical practice remain unclear”.
And by “benefits” they mean increased detection of large for gestational age (big baby) from 27% to 43%.
This study looked at whether or not the introduction of routine 3rd trimester ultrasound changed the outcomes of low-risk pregnancies, that is, single baby, head down, and over 35-weeks’ gestation in an Australian hospital.
Before the policy of routine 35–37-week ultrasound came into effect, 4,826 babies arrived where about 34% of the mothers received a late scan. After the policy, 4,499 babies arrived where 81% received this scan.
The outcomes:
More big babies detected from 27.0% to 43.1%, though 56.9% remained unidentified anyway
Inductions increased from 33.5% to 38.2%
Emergency caesareans (not planned prior to labour) increased from 14.4% to 18%
More total caesareans from 30.1% to 33.9%
Fewer vaginal births from 69.8% to 66%
Surely this meant babies fared better … nope.
No reduction in stillbirth
No reduction in HIE (hypoxic ischemic encephalopathy)
No reduction in low Apgar scores
No reduction in shoulder dystocia
No improvement in composite neonatal outcomes
The study didn’t mention how the mothers fared. No mention of haemorrhage, infection, postpartum PTSD, breastfeeding failure, or the consequences to future pregnancies.
That 3rd trimester scan led to detection of more big babies, more inductions, more c-sections, and no change in the things all these interventions were supposed to prevent.
Now that this useless intervention is in place, it won’t go away. Medicine protects itself and that scan leads to more surgery that rarely gets litigated if the baby comes out ok.
This industry harms healthy mothers because it can. It’s not broken and it’s not going to change until more people stop using it. However, before that happens, we have to break with the idea that all technology is helpful and confers a level of safety despite there being a lack of evidence to justify it. Our faith in technology gives the industry its green light to keep up this nonsense. Until that faith cracks, we’re going to see more mothers and babies needlessly harmed.
We have to do better ourselves.