Birthweights in sickle cell trait pregnancies

Abstract

Objectives Available evidence on the effect of sickle cell trait (SCT) on birthweight is conflicting, not gestational age specific, and does not account for maternal and infant factors. The objectives of this study are to determine the contemporary mean birthweight, mean customised birthweight centile, and to analyse the risk of small-for-gestational-age (SGA) and large-forgestational-age (LGA) babies in SCT pregnancies.Design Large retrospective cohort study.Setting London hospital. Methods All qualifying pregnancies were identified on Terra Nova Healthware. Birthweight centiles of these cases were computed with Gardosi customised bulk centile calculator using collected data on maternal height, weight, ethnicity and parity, and the infant's gender, gestational age and birthweight. Birthweight and birthweight centiles of SCT and pregnancies with no haemoglobinopathy (control) were compared. Statistical analysis was performed using Stata version 9.2.Main outcome measures Birthweight and birthweight centiles.Results Five hundred and five SCT and 16 320 controls were analysed. The mean birthweight of SCT pregnancies was 3223 g, 57 g lower than controls (P = 0.024). However, its mean birthweight centile was 49.0% similar to that of controls' 47.5% (P = 0.320). There is an apparent risk of LGA babies in SCT pregnancies, but logistic regression analysis suggests that the odds are related to being an older non-white parturient and a male infant rather than SCT status.Conclusions SCT is not a risk factor for SGA or LGA infants.Keywords Birthweight, birthweight centile, customised birthweight centile, large for gestational age, sickle cell trait, small for gestational age.

Absence of Association Between Sickle Trait Hemoglobin and Placental Malaria Outcomes

“…Although the prevalence of LBW was slightly lower among newborns born to women with HbAS (9.4%) than with HbAA (11.3%) ( Table 2), this difference was not statistically significant, and mean birth weight overall was 44 g lower in births to women with HbAS ( Figure 3). Prior studies of the association between HbAS and birth weight have yielded mixed results: in some studies, reduced birth weight is more frequent in newborns born to HbAS women, [24][25][26] while in others there was no difference between women with HbAS and HbAA, [27][28][29][30][31] including in two Nigerian studies in malaria-endemic settings. 32,33 Taken together with our data, HbAS does not appear to consistently impact newborn birth weight, and nor does this relationship appear to be modified by malaria endemicity.…”

Birth Weights in Sickle Cell Disease Pregnancies: A Cohort Study

“…St Thomas’ Hospital is a teaching hospital in London, UK which provides specialist tertiary care to a metropolitan patient population. Every pregnant woman receiving treatment at our department is offered and can opt to undergo haemoglobinopathy screening [ 8 , 9 ].…”

“…The midwife attending the delivery had recorded data on the database. These data were used to generate a customised birth weight prediction, which was compared to the infant’s actual weight at birth using the UK Gardosi Bulk Centile Calculator Version 6.6 [ 8 ]. This version of the software uses the gestation related optimal weight standard (GROW) based specifically on the UK population [ 10 ].…”

“…The purpose of this study is to determine whether or not infants born to women with SCD are more prone to LWB, SGA and intrauterine growth restriction (IUGR) than infants born to women without SCD [ 2 ]. As far as we are aware, this study is novel in its use of customised birth weight growth charts to accurately investigate the relationship between maternal SCD and birth weight [ 8 ].…”

Sickle cell trait diagnosis: clinical and social implications

“…54–56 Of the pregnancy-associated complications, asymptomatic bacteriuria has shown the most consistent associations with SCT in the literature. 55,57 …”