{'fraction_non_alphanumeric': 0.03404255319148936, 'fraction_numerical': 0.03723404255319149, 'mean_word_length': 5.580419580419581, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
EARLY ULTRASOUND PREDICTION OF PREGNANCIES AFFECTED BY HOMOZYGOUS α‐THALASSAEMIA‐1

Homozygous α‐thalassaemia‐1 is conventionally diagnosed by invasive testing on all at‐risk pregnancies. We evaluated the diagnostic efficacy of non‐invasive abdominal ultrasonographic cardiothoracic ratio measurement in 62 pregnancies at 13–14 weeks and 75 pregnancies at 17–18 weeks. This performed better than placental thickness measurement. Using a cardiothoracic ratio cut‐off level of ≥0·5, 75 per cent of affected pregnancies were detected at 13–14 weeks and all cases were detected at 17–18 weeks. False‐positive rates were 7 and 8 per cent, respectively. There was no false‐positive diagnosis if the cardiothoracic ratio was ≥0·53. With this approach, invasive procedures can be selectively performed and fewer pregnancies will be lost unnecessarily. The reduction in medical expenses is likely to be substantial. © 1997 by John Wiley & Sons, Ltd.