Knowing a baby’s exact gestational age is essential in antenatal care. It allows midwives and doctors to estimate delivery date, assess the need of medical intervention and make other critical decisions during pregnancy. A recent study suggests that an innovative alternative may be upon us: a highly accurate means of calculating gestational age based on the analysis of the most complex organ of all, the brain.

During the first weeks of pregnancy, the last recorded date menstruation is ordinarily used to establish an estimated due date. During antenatal care, this date can be adjusted according to the information provided by traditional two-dimensional ultrasound imaging of the fetal cranium. This is commonly done after the sixth week of pregnancy.

Lack of accuracy

While many methods have been proposed to better determine the exact age of an embryo or a fetus, in practical terms within the medical community it has been a challenge to find a method which is truly accurate. This has been especially difficult amongst deprived and low income populations, amongst whom factors such as unavailable or unreliable menstrual history and late obstetric care can drastically alter dating information.

During the third trimester of pregnancy in particular, the biological variations in the general development of fetuses means that the correlation between physical form of the fetus and gestational age begins to become divergent.

When the development of a fetus is influenced by external conditions such as malnutrition, the size of the foetus can of course be impacted as well as the development of various bodily systems.

Measurements by brain activity

The brain is generally the last organ to be affected by issues such as malnutrition during gestation, as it is extremely well protected and enduring in its attributes. According to the researchers, calculation of the brain’s activity based on 3D ultrasound image appearance and the patterns generated by the brain can provide us with very specific information about the age of a fetus and its neurodevelopmental maturation.

The scientists claim that their model can provide an accuracy of gestation age of 6-10 days and that it outperforms current clinical methods in calculating gestational age during the third trimester by about 5 days.

This method has never been attempted before and seems very promising especially for assessing gestational age even in cases with deviations in growth.

In future research, the team plan to analyse further correlated factors in assessing the maturation of the fetus, focused around further understanding fetal neurodevelopmental patterns.

References

Namburete, A., Stebbing, R., Kemp, B., Yaqub, M., Papageorghiou, A., & Alison Noble, J. (2015). Learning-based prediction of gestational age from ultrasound images of the fetal brain Medical Image Analysis, 21 (1), 72-86 DOI: 10.1016/j.media.2014.12.006

Namburete, Ana I.L. et al. (2014) Predicting Fetal Neurodevelopmental Age from Ultrasound Images, in Medical Image Computing and Computer-Assisted Intervention–MICCAI 2014, Springer International Publishing.

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