908: Preterm birth etiologies in Marfan syndrome and Loeys-Dietz syndrome

Abstract

Women with Marfan syndrome (MFS) and Loeys-Dietz syndrome (LDS), connective tissue disorders with genetic- predisposition for aortic dissection, have been reported to have a higher rates of preterm birth, but it is unclear whether this is due to iatrogenic or spontaneous causes. The objective of this study was to evaluate the etiology of preterm birth in a cohort of women with MFS and LDS. We conducted a retrospective observational cohort study of women with a clinical and genetic diagnosis of MFS or LDS who had previously been pregnant. Women were recruited through the National Marfan Foundation website and through the connective tissue clinic at Johns Hopkins Hospital. A woman’s first singleton pregnancy was included. Women with incomplete information and those who delivered before 1990 were excluded. The primary outcome was the cause of preterm birth. Women who were diagnosed with MFS/LDS after their pregnancy were also compared to women who received the diagnosis prior to pregnancy in an attempt to identify how medical management changes due to disease diagnosis. A total of 128 pregnancies in women with MFS/LDS were included in the analysis (MFS=104, LDS=24). The total preterm rate in this cohort was 48% (N=61). There was a higher rate of spontaneous preterm birth as compared to iatrogenic preterm birth (87% vs. 13%). Even among women who were not diagnosed with MFS/LDS until after their pregnancy (n= 35), there was a high rate of preterm birth, 45% (N=16), and the majority was spontaneous (94%). As compared to women diagnosed after their pregnancy, those diagnosed prior to their pregnancy were more likely to deliver at an earlier gestational age (36.8 vs. 38.4 weeks, p<0.001), receive general anesthesia (14% vs 3%, p<0.001) and have a cesarean delivery (54% vs 20%, p<0.001). The primary reason for 80% of the cesarean deliveries in the group diagnosed prior to pregnancy was listed as connective tissue disorder. In agreement with previous literature, this study highlights that women with MFS and LDS are at higher risk for preterm birth. This risk appears to be driven by spontaneous rather than iatrogenic preterm birth.