Ultrasound screening for fetal structural abnormalities performed by trained midwives in the second trimester in a low-risk population--an appraisal.

OBJECTIVE: To determine the performance of trained midwives in second trimester ultrasound screening for fetal structural abnormalities in a low-risk population. DESIGN: Retrospective study. SETTING: University Department of Obstetrics and Gynecology. POPULATION: About 13,882 women with singleton pregnancies. METHODS: The findings of routine second trimester anomaly scan performed by midwives were reviewed. Reasons for referral to maternal fetal medicine (MFM) specialists for further assessment were analyzed. MAIN OUTCOME MEASURES: The detection, false positive and false alarm rates for fetal anomalies. RESULTS: One hundred and eighty-nine pregnancies with unknown outcome were excluded from the final analysis. Overall, 617 (4.51%) women were referred to MFM specialists for further assessment, of which 470 (70.2%) were for soft markers alone and 147 (23.8%) for suspected fetal structural abnormalities. In these 13,693 fetuses with known outcome, malformed fetuses were present in 185, a prevalence of 1.35%. Of these, 115 were detected during the second trimester scan and two were detected in the third trimester. The remaining 68 malformed fetuses, most of which had minor anomalies, were identified after birth. The detection rate for a malformed fetus in second trimester scan was 62.2% (115/185) (95% CI 55.2-69.2). There were four cases of false positives and 33 cases of false alarm. CONCLUSIONS: Experienced midwives with proper training can detect the majority of major structural abnormalities. Continuous audit and quality control plays a significant role in optimizing the fetal structural examination.

Expectation and knowledge of pregnant women undergoing first and second trimester ultrasound examination in a Chinese population.

OBJECTIVE: To evaluate expectation and knowledge on obstetric ultrasound examination in the first and second trimester in a Chinese population. METHOD: A cross-sectional survey was conducted in a university obstetric clinic in Hong Kong. Chinese pregnant women who underwent the first trimester early scan sessions, or the second trimester anomaly scan sessions were invited to complete a self-administered questionnaire, which contained items on their knowledge, expectation, and sociodemographic characteristics. RESULTS: In all 276 eligible pregnant women (117 in the first trimester and 159 in the second trimester) were recruited. Although 249 women (90.2%) claimed they understood the indication of the ultrasound examination, only 93 of them were correct (33.7%). The median perceived overall-detection rate for structural abnormalities was 66.5%. Living in Hong Kong for more than 7 years was significantly associated with higher knowledge level and expectation from ultrasound examination. Attaining tertiary education level was also significantly associated with higher knowledge level. Over 90% of the pregnant women studied wished to know the fetal gender from the anomaly scan examination. CONCLUSION: Knowledge of Chinese pregnant women on ultrasound was generally unsatisfactory. Understanding their limitation of knowledge and expectations helps to devise appropriate education in the local setting.

Expectation and knowledge of women undergoing first-trimester combined screening for Down syndrome in a Chinese population.

OBJECTIVES: To study the preference of pregnant women regarding the time taken to report the results of first-trimester combined screening for Down syndrome and their knowledge about it. METHODS: A questionnaire survey was conducted on a cohort of 325 pregnant participants who attended our first-trimester combined nuchal translucency and biochemical screening programme for fetal Down syndrome. This service was operated in a one-stop setting and the result of the screening test was available within 1 to 2 h after the collection of blood sample. RESULTS: The majority of participants: (1) could recall the quoted detection rate correctly (96.6%); (2) understood that a negative test does not exclude Down syndrome (91.1%); (3) understood that a positive test does not equate to an affected fetus (91.0%), and (4) could decide on the need for further invasive tests on the basis of the screening test results (98.1%). Twenty-nine percent of participants considered that a one-stop setting was very important because any delay in releasing the results made a significant difference to them, while 48.9% considered it acceptable if the results were available on the same day. The percentage dropped dramatically to 6.3% (within 2 days), 6.7% (within 3 days), 5.7% (within 1 week), and 3.1% (more than 1 week). CONCLUSION: The majority of the pregnant women in our test considered same day reporting of screening test results to be no different from a one-stop clinic. This would have important implications for the organisation and structuring of our service provision, since the operation of a one-stop clinic imposes significant stresses on the clinical staff involved.