Pregnancy loss after first-trimester viability in women with sickle cell trait: time for a reappraisal?

OBJECTIVE

The purpose of this study was to evaluate the obstetric outcomes and pathologic findings in women with sickle cell trait.

STUDY DESIGN

In this retrospective case control study, pregnant women with sickle cell trait were studied over a 4-year period (2001-2005). The women who were delivered at > 16 weeks of gestation were compared with a cohort group of subjects with normal hemoglobin levels, and the placentas were sent for pathologic evaluation.

RESULTS

A total of 180 pregnancies were studied with a like number of control patients. Subjects who had sickle cell trait demonstrated shorter average duration of pregnancy (233 +/- 45 days vs 255 +/- 34 days; P < .001) and lower birth weight (2114 +/- 1093 g vs 2672 +/- 942 g; P < .001). The rate of fetal death was significantly higher among study group patients (3.5% vs 9.7%; P = .015) when compared with the control group. Additionally, in study women, acute ascending amniotic infection and meconium histiocytosis were noted much more frequently. Sickling in the intervillous space and decidual vessels that were not associated with artifactual change was also found among patients sickle cell trait.

CONCLUSION

Patients with sickle cell trait appear to be at increased risk for fetal loss compared with women with normal hemoglobin levels, and placental abnormalities may play a causal role.