Comparison of noninvasive prenatal screening with combined first-trimester screening as a frontline screening approach for common trisomies in a public hospital in Australia

BACKGROUND

Combined first-trimester screening (cFTS) for fetal anomalies involves maternal serum screening for biochemical markers and measurement of the nuchal translucency (NT) by ultrasound. Noninvasive prenatal screening (NIPS) analyses cell-free DNA present in a maternal blood sample for presence of fetal chromosomal aneuploidies.

AIMS

To compare NIPS with cFTS as frontline screening in a public hospital in Australia.

MATERIALS AND METHODS

Women were offered NIPS in addition to the usual cFTS routinely offered to all women at a public hospital in NSW, Australia. The cFTS sample was collected at ten weeks' gestation and the NIPS sample at 12 weeks' gestation at the ultrasound appointment.

RESULTS

In a low-risk population of 997 women, frontline NIPS had a screen-positive rate of 0.5% (5/997) vs 4.2% (42/997) with cFTS. cFTS correctly identified one trisomy 21 case and one trisomy 18 case; however, there were two trisomy 18 false negatives. Of five positive NIPS calls, four were correctly identified as trisomy 21 (one) and trisomy 18 (three); there were no NIPS false negatives. Overall, the false-positive rate with NIPS was 0.1% vs 4.0% by cFTS.

CONCLUSIONS

The lower screen-positive rate with NIPS for common trisomies was a result of the significantly lower false-positive rate with NIPS. Consequently, NIPS as first-line screening, even if funded by the hospital, may provide cost savings. We believe NIPS should be used from ten weeks' gestation in conjunction with morphology ultrasound for routine first-trimester prenatal management.

Awareness About Folic Acid Supplementation in First-Trimester Pregnant Women of Rural Raipur District, Chhattisgarh, and Its Determinants: A Cross-Sectional Study

BACKGROUND

Women are supplemented with folic acid (FA) during pregnancy as well as preconceptionally to prevent neural tube defects (NTDs) in newborns. To understand the importance of FA supplementation, women need to have awareness about the same, which in turn may be influenced by different factors. It is also known that both FA and vitamin B12 deficiency tend to cause NTDs in newborns and anemia. Very few studies have studied the relationship between hemoglobin, FA, and vitamin B12 levels. In this study, we aim to estimate the level of awareness of FA supplementation among pregnant women in the first trimester of pregnancy and the factors determining the presence of awareness regarding the same. Also, we aim to estimate any correlation between hemoglobin, FA, and vitamin B12 levels among a subset of pregnant women.

METHODS

A cross-sectional study was conducted in the Abhanpur Block of Raipur district in Chhattisgarh among 399 pregnant women in their first trimester of pregnancy, in which their knowledge was assessed using a pretested semistructured questionnaire. Each participant's knowledge score regarding FA supplementation was calculated and scored based on six indicators and classified as low, intermediate, and high scores. Logistic regression was applied to find out any significant association between knowledge about FA supplementation with any other sociodemographic variables. Scatter plots were used to assess the correlation of FA with hemoglobin, vitamin B12, and knowledge scores among 104 participants.

RESULTS

The majority (77.9%) of women had low knowledge scores with a mean score of 1.4 (0.15). It was found that only 45.6% of the participants knew the importance of FA supplementation, and the majority (23.1%) were informed by auxiliary nurse midwives (ANMs) followed by doctors. The majority (41.6%) of the study participants also did not know when to start FA, and only 1.3% knew that FA should be taken preconceptionally. On multivariable logistic regression, women who lived in joint families had significantly higher odds of having intermediate knowledge compared to those who lived in nuclear families. Although not statistically significant, there was a positive correlation between serum vitamin B12 and FA levels and also between hemoglobin and serum FA levels. However, a significant positive correlation was found between serum FA levels and the knowledge scores of the study participants.

CONCLUSION

The majority of study participants had poor knowledge and awareness regarding FA supplementation. So, health education, as well as information, education, and communication (IEC) activities, is required to improve the knowledge about FA supplementation among women of reproductive age in the community. A better understanding of FA supplementation can lead to adherence to FA consumption and prevent NTDs among newborns.

Proficiency testing of maternal serum prenatal screening in second trimester in China, 2015

Introduction

Prenatal screening and diagnosis is important for the detection of birth defects and genetic diseases. The nationwide proficiency testing (PT) of maternal serum prenatal screening in second trimester in China has been launched since 2003 and partly reflected the performance of screening laboratories. This study analysed the 2015 PT results to examine the performance of clinical laboratories and different platforms.

Materials and methods

Fifteen lyophilized samples with different concentrations divided into three panels, were distributed to 613 clinical laboratories in 2015. Acceptable performance was defined as scores more than 80% of acceptable responses with the evaluation criterion of ± 30%. The robust coefficient of variation (CV) was also analysed. Chi-square (χ2) test was used to compare the acceptable performance while Kruskal-Wallis test and Mann-Whitney test were applied to compare the robust CV among analytes and mainstream platforms.

Results

Overall, 605, 61, 214, 416, 303 laboratories submitted effective results for alpha fetoprotein (AFP), total human chorionic gonadotropin (t-hCG), β-hCG, unconjugated estriol (uE3) and free β-hCG. The acceptable performances of AFP (μg/L), AFP (KIU/L), t-hCG, β-hCG, uE3, and free β-hCG were 98.45%, 99.24%, 95.58%, 98.72%, 94.50%, and 98.66%, respectively. The χ2 test indicated significant differences existed in the acceptable performances among different analytes and platforms for uE3. Kruskal-Wallis test and Mann-Whitney test suggested the robust CV differed significantly in different analytes and platforms.

Conclusions

The majority of results were acceptable. However, further effort is needed to achieve the standardization and harmonization among analytes and various platforms, particularly for uE3.