Genetic causes of sporadic and recurrent miscarriage

The role of the annexin A protein family at the maternal-fetal interface

Successful pregnancy requires the tolerance of the maternal immune system for the semi-allogeneic embryo, as well as a synchrony between the receptive endometrium and the competent embryo. The annexin family belongs to calcium-regulated phospholipid-binding protein, which functions as a membrane skeleton to stabilize the lipid bilayer and participate in various biological processes in humans. There is an abundance of the annexin family at the maternal-fetal interface, and it exerts a crucial role in embryo implantation and the subsequent development of the placenta. Altered expression of the annexin family and dysfunction of annexin proteins or polymorphisms of the ANXA gene are involved in a range of pregnancy complications. In this review, we summarize the current knowledge of the annexin A protein family at the maternal-fetal interface and its association with female reproductive disorders, suggesting the use of ANXA as the potential therapeutic target in the clinical diagnosis and treatment of pregnancy complications.

Causal association between rheumatoid arthritis and pregnancy loss and intrauterine growth retardation: A bidirectional two-sample Mendelian randomization study

OBJECTIVE

To investigate the causal relationship between rheumatoid arthritis (RA) and pregnancy loss and intrauterine growth retardation (IUGR) using Mendelian randomization (MR).

METHODS

Genetic variants associated with RA (12,555 cases and 240,862 controls), miscarriage (1475 cases and 149,622 controls), and IUGR (3558 cases and 207,312 controls) were obtained from the FinnGen consortium, and supplementary data on RA (5201 cases and 457,732 controls) and miscarriage (7069 cases and 250,492 controls) were obtained from the Medical Research Council Integrated Epidemiology Unit (MRC-IEU). 47 Single nucleotide polymorphisms (SNPs) associated with RA were screened as instrumental variables (IV). The causal relationship between RA and pregnancy loss and IUGR were assessed by 5 MR methods, mainly inverse variance weighting (IVW). Sensitivity analyses were also performed to test the stability of the results.

RESULTS

Bidirectional MR showed that genetically predicted RA was causally associated with pregnancy loss and IUGR in forward MR analyses, and that RA significantly increased pregnancy loss [odds ratio (OR) = 1.13, 95% confidence interval (CI): 1.00-1.33, P = .03] and IUGR (OR = 1.08, 95% CI: 1.01-1.15, P = .019). In the reverse MR, there was no causal association between pregnancy loss (P = .15) and IUGR (P = .87) and RA.

CONCLUSION

This study found a significant genetic association between RA and pregnancy loss and IUGR. RA is considered to be a high-risk factor for adverse maternal outcomes. Pre-pregnancy prophylaxis and intra-pregnancy control of patients should be emphasized to reduce the incidence of adverse pregnancy outcomes such as pregnancy loss and IUGR.