breech presentations

A recent study has revealed how an unacceptably high occurrence of missed breech presentations could be improved. Researchers suggest that providing all expectant mothers with a third-trimester ultrasound scan could significantly decrease the occurrence of undiagnosed breech presentations by over two-thirds.

Featured in PLOS Medicine, the research highlights that breech presentations at term have a 3-4% prevalence, with breech vaginal deliveries correlating to heightened perinatal and maternal morbidity and mortality.

When expectant mothers are informed of a breech presentation, they can effectively weigh the pros and cons of their choices. Here we look at what the latest study found and why third trimester ultrasound could prove essential for expectant mothers.

Current level of missed breech presentations is unacceptable

The latest study was carried out by the Norfolk and Norwich University Hospital NHS Foundation Trust, alongside the St George’s University Hospital NHS Foundation Trust in London. It revealed the rates of overlooked breech or non-cephalic presentations are alarmingly high. Also, the current clinical examination methods fail to provide sufficient accuracy in determining foetal presentation.

For instance, abdominal palpation exhibits a meagre sensitivity of 50-70%. To assess the effectiveness of reducing undiagnosed term breech presentations, the research team compared pre- and post-screening periods. They did this by examining the implementation of policies involving routine third-trimester ultrasound performed by sonographers (at St. George’s) or point-of-care ultrasound (POCUS) conducted by trained midwives using handheld devices (at Norwich).

A third trimester scan could drastically reduce undiagnosed breech

One of the most substantial findings of the study was that the percentage of undetected term breech presentations significantly decreased after introducing routine third-trimester ultrasound scans. The rate dropped from 14.2% to 2.8% with sonographer-perform ultrasounds, and from 16.2% to 3.5% with POCUS.

The research used Bayesian regression analysis, which showed a 71% reduction in undiagnosed breech presentations after implementing universal ultrasound policies. This result had a probability of more than 99.9%.

It also revealed a reduction in emergency C-sections from 12.9% to 11.5% after introducing screening policies. However, elective C-section rates slightly increased during this period (from 12.0% to 13.0%).

The findings showed improvements in short-term perinatal outcomes for pregnancies with diagnosed breech presentations at term. These improvements included a decrease in low Apgar scores (less than 7 at 5 minutes), hypoxic-ischemic encephalopathy, unexpected neonatal unit admissions, and extended perinatal mortality rates.

UK lacking skilled providers for breech births

While research indicates that pregnant women may opt for planned breech vaginal births, a significant number of maternity units in the UK lack the expertise to facilitate these deliveries.

Early detection of breech presentation would allow expectant mothers to make informed decisions and enjoy more positive birthing experiences.

One of the main challenges of implementing routine third-trimester scan policies is the associated costs. However, a review by the National Institute for Health Research Health Technology Assessment proposes that handheld portable ultrasounds could bridge this gap as an affordable alternative. These devices would allow antenatal care providers, such as midwives, to detect foetal presentations with minimal training.

While the NHS doesn’t currently offer third semester presentation scans, there are alternatives. SureScan provides a presentation scan after 36 weeks to provide reassurance that your baby is developing exactly as they should.