Antenatal haemoglobinopathy screening: Patterns within a large obstetric service. Working towards a standard of care

Abstract

Background: Antenatal screening can predict clinically significant haemoglobinopathies, however in Australia, practices are not standardised and are evolving as the population becomes more ethnically diverse. This study describes antenatal screening practices in a large Australian laboratory/antenatal service.

Methods: Data were collected retrospectively on consecutive antenatal haemoglobin electrophoresis over 16 months and correlated with obstetric data, obtained from the local obstetric database.

Results: 462 patients were included, with an average gestation of 25.8 weeks. 'Pregnancy' was the most common stated indication, with absent indication/clinical information in 8%. Gestational age was documented in 54%. In 15%, no contact details of the referrer were documented and partner screening was traceable in only 25 cases (5.4%). In 82% of cases, no abnormalities were detected. Beta thalassemia trait was the most common positive result. Only 52% of patients had recent iron studies. The mean haemoglobin was 111.6 g/L and mean cell volume was 80.5 fl at the time of testing. Ethnicity was documented on the request form in 3%. After Australasia, the most common ethnicity of patients was South East Asia and the Middle East.

Conclusion: Referral patterns in our health service are diverse and reflect our changing population and care practices. Detailed guidelines are required and we propose a comprehensive algorithm for general use where selective screening is practiced within an Australasian population or one with similar demographics.

Keywords: Haemoglobinopathies; anaemia; genetic diseases; pregnancy; thalassemia.

Figure 1.

Ethnicity according to place of birth from linkage.

Figure 2.

Antenatal haemoglobinopathy selective screening algorithm.