Search

Competing Interests: Conflict of Interest None declared.

Antiphospholipid (aPL) antibodies are recognised risk factors for adverse obstetric outcomes. Recently, carriers of the M2 haplotype in the Annexin A5 gene have been shown to have a higher susceptibility to develop aPL antibodies. In a general obstetric population, we prospectively evaluated the possible relationship between: (1) aPL antibodies and M2 haplotype; and (2) aPL antibodies and/or M2 haplotype and obstetric outcomes. From a cohort of 3,097 consecutive pregnant women, 1,286 samples were analysed for the presence of both anti-cardiolipin and anti-human β2-glycoprotein I antibodies; samples with available DNA ( n  = 606) were also investigated for the M2 haplotype. Overall, 41/1,286 (3.2%) women showed the presence of aPL antibodies. Among them, 2 (4.8%) experienced a pregnancy loss and 38 (92.7%) gave birth to live-born babies ( p -value = non-significant vs. those without aPL antibodies). M2 haplotype was identified in 140 (23.1%) out of 606 women with DNA available: 3/140 (2.1%) M2 carriers and 17/466 (3.6%) non-carriers tested positive for aPL antibodies, respectively ( p -value = non-significant). In total, 15/150 (10%) M2 and/or aPL antibody carriers, and 38/445 (8.5%) non-aPL antibody and/or M2 carriers suffered from obstetric complications, respectively ( p -value = non-significant). No relationship between aPL antibodies and M2 haplotype was found. Furthermore, neither aPL antibodies nor the M2 haplotype is associated with obstetric complications., Competing Interests: Disclosure The authors report no conflicts of interest in this work., (Georg Thieme Verlag KG Stuttgart · New York.)

Inherited or acquired thrombophilias have been largely explored as a cause of pregnancy complications. However, pathogenesis of obstetric complications, as fetal loss and pregnancy-related hypertensive disorders is still partly unexplained. Recently, a common haplotype (M2) within the annexin A5 (ANXA5) gene has been described as a risk factor in recurrent fetal losses (RFL). It has been demonstrated to reduce the promoter activity of the ANXA5 promoter in luciferase reporter assays. Aim of this study was to investigate the prevalence of M2 haplotype in three different settings of women with previous obstetric complications: RFL, intra-uterine fetal death (IUFD) and pregnancy-related hypertension (gestational hypertension [GH] and pre-eclampsia [PE]). One hundred three patients with previous RFL, 54 with IUFD, 158 with hypertensive disease (67 GH, 91 PE) were investigated. As controls, 195 women from the same ethnic background with uneventful pregnancies were enrolled. Logistic regression, correcting for age, gravidity and parity showed that the ANXA5 haplotype is significantly and independently associated with the occurrence of RFL (3.1; 95%CI: 1.1-9.5; p = 0.047) and pregnancy-related hypertensive disorders (2.1; 95%CI: 1.2-3.5; p = 0.008). The M2 haplotype might be a new and relevant risk factor for obstetric complications.