Increased false positive Down syndrome screening in women with sickle cell anemia.

OBJECTIVES: This study seeks to determine whether there is a higher rate of false positive serum screening for Down syndrome in women with sickle cell anemia and, if so, which markers contribute to the false positive screen. METHODS: This is a retrospective cohort study of women who had serum screening between 1998 and 2011. Subjects were women with sickle cell anemia (n = 13), and controls were African American women who did not have that disease (n = 91). The populations were compared using basic inferential statistics. RESULTS: The positive screen rate was 38.5% (5/13) in women with sickle cell anemia and 7.7% (7/91) in the control population (odds ratio 7.5, 95% confidence interval 1.6-35.8, P = 0.001). At the average age of the cases (25 years), the expected false positive rate is only 2%. The human chorionic gonadotrophin values were significantly higher in cases than controls (2.00 and 1.30 MoM, P = 0.017), whereas levels of other serum analytes were similar. None of the screen positive results were associated with a fetus or neonate affected by Down syndrome. CONCLUSIONS: The false positive Down syndrome serum screen rate is significantly higher in patients with sickle cell anemia than in African American women without that disease. The human chorionic gonadotrophin values were significantly higher in cases than controls, suggesting that placental factors may contribute to the elevated false positive rate. © 2015 John Wiley & Sons, Ltd.

Postpartum Depression in Women with the FMR1 Premutation.

BACKGROUND: Psychiatric disorders in women with the FMR1 premutation are common and include attention deficit hyperactivity disorder, anxiety, depression, and eating disorders. This pilot study explored the risk factors for postpartum depression (PPD) in women with the premutation. METHODS: We conducted a chart review of 50 women premutation carriers with major depressive disorder who had children. Of these, 7 women had a history of major depressive episodes in the postpartum period. The PPD and non-PPD groups were characterized descriptively based on women's age at the time of the psychiatric evaluation, race, ethnicity, education level, IQ, CGG repeat size, comorbid psychiatric conditions, parity, and number of children with fragile X syndrome (FXS). Exact logistic regression was used to analyze the relationship between the number of children with FXS and the risk of PPD. RESULTS: The PPD and non-PPD groups were similar on all variables examined, with the exception of the number of affected children. Each of the 7 women with PPD had at least one child with FXS, whereas a third of the women without PPD had no affected children. For each additional affected child, the risk of PPD increased by 158% (exact odds ratio 2.58, 95% CI 0.99-7.59). Further studies are needed to replicate these findings and to better characterize PPD in female premutation carriers.