Application of obstetric ultrasound to determine the most suitable parameters for the aging of formalin-fixed human fetuses using manual measurements

Pregnant women's knowledge, attitude, and associated factors toward obstetric ultrasound in public hospitals, Ethiopia, 2021: Multi-centered cross-sectional study

BACKGROUND

Obstetric ultrasound is a harmless, cheap, and noninvasive imaging modality that helps to scan a pregnant mother and delivers parents with a real-time image of the fetus. As the number of pregnancies rises globally, the demand for obstetric ultrasound becomes even more pressing.

OBJECTIVES

To assess pregnant women's knowledge, attitude, and associated factors toward obstetric ultrasound in public hospitals, Ethiopia.

METHODS

Institutional based cross-sectional study was employed. Systematic random technique was used to select 419 pregnant women from 10 April 2021 through 2 June 2021. A structured questionnaire was used to collect data during a face-to-face interview. Then the data were coded, cleaned, and entered into Epidemiological data version (EPIDATA) 3.1 and exported to the statistical package for Social Science version 23.0 for analyses. Bivariate and multivariable logistic regression model was used to identify statistically significant associations between dependent and independent variables. The odds ratio at 95% confidence interval with p-value 0.05% was considered statistically significant.

RESULT

The majority of the study participants, 179 (42.8%), have ages ⩾ 25 years. Magnitude of having good knowledge and positive attitude of pregnant women toward obstetric ultrasound was 35.5% and 69.5%, respectively. Residence (adjusted odds ratio: 3.934; 95% confidence interval: 3.125-6.761), educational status (adjusted odds ratio: 3.614; 95% confidence interval: 1.986-5.964), and parity (adjusted odds ratio: 2.7621; 95% confidence interval: 1.68-3.275) were significantly associated with knowledge. Whereas exposure to obstetrical ultrasound in current pregnancy (adjusted odds ratio: 2.726; 95% confidence interval: 1.632-3.629), knowledge on obstetrical ultrasound (adjusted odds ratio: 3.92; 95% confidence interval: 1.324-3.120), and educational status (adjusted odds ratio: 2.84; 95% confidence interval: 1.337-3.381) were significantly associated with attitude.

CONCLUSION

The level of good knowledge and positive attitude toward obstetric ultrasound was 35.5% and 69.5%, respectively, and it can be improved with appropriate interventions like ensuring the practice of obstetric ultrasound scan to all antenatal women. Obstetric care providers at the antenatal care units should advice pregnant women for obstetric ultrasound scan as per World Health Organization recommendations of one obstetric ultrasound scan before 24 weeks of gestation.

A revisit of the fetal foot length and fetal measurements in early pregnancy sonography

Objectives

To present the fetal measurements in relation to the foot length at 10–16 weeks gestation on antenatal ultrasound.

Materials and methods

We reviewed the fetal measurements in 47 scans performed at 10–16 weeks gestation in women attending routine antenatal care. The fetal measurements and measurement ratios were examined in relation to the foot length.

Results

The fetal biparietal diameter, head circumference, abdominal circumference, femur length and foot length increase linearly with the gestational age at 10–16 weeks gestation. The correlation between fetal foot length and fetal biparietal diameter, head circumference, abdominal circumference and femur length are better than with the crown rump length. The femur length to foot length ratio and the femur length to abdominal circumference ratios increase with the gestational age in an inverse relationship throughout the same period.

Conclusion

Fetal foot length is an accurate estimate of the gestational age in early pregnancy. Compared with crown rump length, the correlation between foot length and other fetal measurements is better. The fetal measurements ratios are gestational age dependent between 10–16 weeks. Gestational age specific ratio should be used in this period.

Subclassification of anencephalic human fetuses according to morphology of the posterior cranial fossa

Anencephaly is a designation for congenital absence of the cranial vault with cerebral hemispheres completely missing or decreased to small masses attached to the base of the skull. The etiology is unknown. Whether the bony tissue or soft brain tissue is a primary factor is also unknown. The present study has focused on the posterior cranial fossa in anencephaly. The goal is to determine whether differences in the posterior cranial fossa could provide a basis for subclassification of anencephalic fetal skeletons. Twenty-three human anencephalic fetuses, at gestational ages 13 to 22 weeks, were studied. Radiologic and cephalometric analyses, including measurements of bone sizes and different angles, were performed. Permission for autopsy of the central nervous system was not available. For comparison of anencephalic findings with normal conditions, standards from a recent publication were used. Foot length served as a parameter for age comparison. The study showed 2 morphologic types of the posterior cranial fossa. One type had a fossa cranial morphology close to normal morphology, whereas the other had a malformed and much smaller posterior cranial fossa. The latter condition was presumed to be due to a primary error in chondral and cranial development. The current skeletal subgrouping might be essential for clinicians' or pathologists' future assessment of the autopsy results. The skeletal subgrouping should, if possible, be associated with karyotyping and analysis of the central nervous system. The goal is to distinguish between congenital conditions resulting in anencephaly and acquired conditions resulting in anencephaly.

[New formula for the determination od fetal age]

The methods utilised in anthropology for foetal age assessment are generally rather old, based on small samples and have never been tested on other samples than the one they were established on. In this study, we establish a formula on 344 foetuses of known age, and compare it with other age determination methods found in the scientific literature. Except our formula, the tested other methods do not give the limits of the prediction's confidence interval, and therefore do not take into account the total variability. Therefore, we demonstrate the necessity to establish formulas based on large samples and on a validated methodology.

Prenatal ages and stages-measures and errors

BACKGROUND

The confusing term "gestational age" is generally either not defined or is used for menstrual "age," postovulatory age, or postfertilizational age. The designation (post)menstrual weeks and/or days is very useful in obstetrics but, because prenatal age extends from fertilization to birth, menstrual "age" is a misnomer. The term "stage" has a specific morphological meaning in embryology and should not be used either for ages or for lengths.

METHODS

Embryonic age is best assessed, when possible, from the 23 internationally recognized morphological stages. A morphological staging system is not available for the fetal period, and fetal age is assessed mainly from measurements.

RESULTS

Among these, the unsatisfactory designation crown-rump length (CRL) should be replaced, in ultrasonic biometry as well as in embryology, by the greatest length (GL), exclusive of the lower limbs. These points are discussed in detail, and justification for the views expressed is provided.

CONCLUSIONS

The continuing confusion concerning prenatal age is shown to be unnecessary once the ambiguous and superfluous term "gestational age" is abandoned.