AFJOG

African Journal of Obstetrics and Gynaecology | Volume 2 | Issue 3 | 2024 | 28 ORIGINAL RESEARCH African Journal of Obstetrics and Gynaecology | Volume 2 | Issue 3 | 2024 | The role of foot length measurement to determine the gestational age in stillbirths gestational age from foot length found a highly significant correlation between foot length gestational age and certain gestational age. 9 Similarly, other investigators showed the correlation between foot length and gestational age, both prenatally by ultrasound and post-mortem examinations. 10,16-19 However, the correlation coefficient measures the strength of the relationship between two variables, not their agreement. Agreement between two methods implies that they may be used interchangeably. In our data, nearly half (42.7%) of the overall stillbirths had an unacceptably inaccurate absolute difference greater than two weeks. The EUS population 19 (54.3%) has by far the least percentage of accuracy. The Bland Altman plot of the EUS population showed a clinically significant lack of agreement between the two methods. Although the overall foot length gestational age was smaller compared to the EUS gestational age, there is an even distribution, with data points below and above the limits of agreement on the Bland Altman plot; this eliminates the presence of fixed bias. There appears to be an overestimated dating ultrasound for these stillbirths plotted to be appropriate for gestational age, and an underestimated dating gestational age in large stillbirths for gestational age. This underlines the need to reflect on the ultrasound skills among the healthcare workers. Over- or underestimation of gestational age may potentially mask the role of intrauterine fetal growth restriction or accelerated growth in the pathogenesis of fetal death. The largest category of perinatal deaths in South Africa is unexplained stillbirth, of which up to 25% have fetal growth restriction. 20 Using the Merz chart to determine the gestational age, Van Wyk et al. found that foot length gestational age correlates well with the actual gestational age. 9 However, in their study, Van Wyk et al. did not evaluate the performance of the foot length measurement using the Bland Altman plot. The current study confirmed that the accuracy of foot length in predicting gestational age decreases with intrauterine growth restriction. Overall, in 14 (17.1%) stillbirths, six of them (42.8%) had an accurately dated pregnancy with an EUS. The effects of fetal growth on overall birthweight can perhaps affect foot length measurements, as subcutaneous fat is decreased in the small for gestational age stillborn babies and increased in the large for gestational age stillborn babies. These outcomes emphasize the need for improved identification of fetal growth restriction, accompanied by optimal surveillance and timely delivery to reduce small for gestational-age and growth restricted stillbirths. Antenatal stillbirths represent macerated stillbirths, and better antenatal surveillance is needed to prevent macerated stillbirths. Thus, this study demonstrated that the presence of maceration affected the foot length's predictive accuracy. This study report coincides with implementation of the South African Basic Antenatal Care Plus (BANC Plus) 21 aimed at reducing preventable antenatal morbidity and mortality, and perhaps BANC Plus will impact the rate of macerated stillbirths. The SD population had the highest accurate cases. This can be explained by increasing female literacy, as most of these women have basic education and can keep track of their menstrual cycle. This highlights that sure LNMP dates can be used reliably in women presenting late for antenatal care with a regular pregestational menstrual cycle. The SFH population had the least foot length derived gestational age mean difference. These findings mean the two gestational ages corresponded. The limitation is that these two methods (SFH and foot length) may mask the possible underlying intrauterine growth abnormality which may have been present prior to fetal demise. These findings mean this method is unreliable, and needs more rigorous evaluation. STUDY STRENGTHS AND LIMITATIONS There are several limitations to this study. The study population is small, resulting in some statistical analyses being underpowered, although the findings are similar to previous studies. 10, 12, 13 All the measurements were not collected by the same investigator, however, they were validated bymeasuring the footprint, which revealed a highly significant correlation between the two measurements. In addition to this, no post-mortem was done to evaluate the actual cause of death, and there might have been underlying causes that may have had an impact on the accuracy of foot length measurement. Furthermore, ethnical differences may impact the accuracy of using the Merz model and Fenton growth charts. Despite the limitations of the study, the strength of the study was a widely distributed gestation from 25 weeks to full term. The findings of a statistically significant wide agreement interval imply no significant proportional bias. CONCLUSION This study showed that foot length measurement in stillborn infants lacked accuracy in determining the gestational age, particularly in the presence of intrauterine growth restriction and maceration. REFERENCES ¡ ¤ ¥ £ ¤ ¥ _ _ ¤ ¥ ¤ ¥ ¡ ¡ £ £ ¦ ¾ ¦ ¦ £ ¡ ¦ £ £ « ¦ £ ¡ ¦ ¦ ¦ £