Pregnancy outcomes among women affected with thalassemia traits.

OBJECTIVE: To compare the maternal and perinatal outcomes between a group of pregnant women diagnosed with thalassemia traits and normal controls. STUDY DESIGN: A retrospective cohort study was conducted on singleton pregnant women affected and unaffected by thalassemia traits who attended an antenatal care clinic and delivered in Siriraj Hospital. Thalassemia status for all subjects was diagnosed by hemoglobin typing and/or DNA analysis. Patient charts were reviewed from January 2007 to December 2018. The control participants were randomly selected from the same period, with a control-case ratio of around 1:1. RESULTS: Overall, 1288 women with thalassemia traits (348 with α thal-1 trait, 424 with ß thal trait and 516 with HbE trait) and 1305 women in the control group were recruited. Baseline characteristics of both groups were similar, with the exception that the hematocrit level in the first trimester in the thalassemia trait group was significantly lower than that in the control group (34.8 ± 3.4% VS 36.9 ± 3.0%; p < 0.001). The prevalence of pregnancy-induced hypertension (PIH) was higher in the thalassemia trait group, at 6.9% VS 4.7% in the control group; p = 0.018. When subgroups were analyzed between each thalassemia trait, the number of maternal anemias in the first and third trimester was higher for all thalassemia traits compared to the normal group. The ß thal and HbE traits increased the risk of PIH, with a relative risk (RR) = 1.67 and 1.66, respectively. CONCLUSIONS: Thalassemia traits minimally but significantly increase the risk of hypertensive disorders and maternal anemia. In addition, physiological changes during pregnancy may worsen the severity of anemia in the pregnant women with thalassemia traits.

Incidence of large for gestational age and predictive values of third-trimester ultrasound among pregnant women with false-positive glucose challenge test.

This cohort study aimed to determine the association between false-positive 50-g GCT and incidence of LGA and to evaluate predictive roles of third-trimester ultrasonographic examination. A total of 200 women with false-positive 50-g GCT and 188 women without GDM risks were enrolled. Third-trimester ultrasonographic examinations were offered. Rate of LGA during third trimester and at birth were compared between groups. Factors associated with LGA and diagnostic properties of third-trimester ultrasonography were evaluated. Incidence of LGA by third-trimester ultrasound and at birth were significantly higher in women with false-positive GCT (19.0% vs. 10.6%, p = .03 and 22% vs. 13.8%; p = .04). Factors associated with LGA included multiparity (adjusted OR 2.32, p = .01), excessive weight gain (adjusted OR 2.57, p = .01) and LGA by ultrasound (adjusted OR 9.79, p < .001). Third-trimester ultrasonography had 47.1% sensitivity, 92.1% specificity and LR + and LR- of 5.96 and 0.57 in identifying LGA infants.Impact statementWhat is already known on this subject? Women with abnormal GCT but normal OGTT (false positive GCT) might have some degree of glucose intolerance so that GDM-related outcomes could develop, including LGA, macrosomia, shoulder dystocia, and caesarean delivery. Roles of ultrasonography in the prediction of LGA and macrosomia has been reported with mixed results.What do the results of this study add? The results showed that the incidence of LGA, by third-trimester ultrasound and at birth, were significantly increased in women with false-positive GCT. Multiparity, excessive weight gain and LGA by third-trimester ultrasound significantly increased the risk of LGA. Third-trimester ultrasonography had 47.1% sensitivity, 92.1% specificity and LR + and LR- of 5.96 and 0.57 in identifying LGA infants.What are the implications of these findings for clinical practice and/or further research? More intensive behavioural and dietary interventions, together with weight gain control and monitoring, may be needed in women with false-positive GCT to minimise the risk of LGA. Third trimester ultrasonographic examination might be helpful to detect and predict LGA at birth and should be included into routine clinical practice. Further studies that are more widely generalisable are needed to elucidate the relationship between false-positive GCT and adverse pregnancy outcomes and to investigate the benefits of ultrasonographic examination in the prediction of LGA and macrosomia.

Intrapartum prediction of birth weight with a simplified algorithmic approach derived from maternal characteristics.

Objective To derive and validate a population-specific multivariate approach for birth weight (BW) prediction based on quantitative intrapartum assessment of maternal characteristics by means of an algorithmic method in low-risk women. Methods The derivation part (n = 200) prospectively explored 10 variables to create the best-fit algorithms (70% correct estimates within ±10% of actual BW) for prediction of BW at term; vertex presentation with engagement. The algorithm was then cross validated with samples of unrelated cases (n = 280) to compare the accuracy with the routine abdominal palpation method. Results The best-fit algorithms were parity-specific. The derived simplified algorithms were (1) BW (g) = 100 [(0.42 × symphysis-fundal height (SFH; cm)) + gestational age at delivery (GA; weeks) - 25] in nulliparous, and (2) BW (g) = 100 [(0.42 × SFH (cm)) + GA - 23] in multiparous. Cross validation showed an overall 69.3% accuracy within ±10% of actual BW, which exceeded routine abdominal palpation (60.4%) (P = 0.019). The algorithmic BW prediction was significantly more accurate than routine abdominal palpation in women with the following characteristics: BW 2500-4000 g, multiparous, pre-pregnancy weight <50 kg, current weight <60 kg, height <155 cm, body mass index (BMI) <18.5 kg/m2, cervical dilatation 3-5 cm, station <0, intact membranes, SFH 30-39 cm, maternal abdominal circumference (mAC) <90 cm, mid-upper arm circumference (MUAC) <25 cm and female gender of the neonates (P < 0.05). Conclusion An overall accuracy of term BW prediction by our simplified algorithms exceeded that of routine abdominal palpation.