H1299R Variant in Factor V and Recurrent Pregnancy Loss: A Systematic Review and Meta-Analysis Protocol

Abstract

Recurrent pregnancy loss (RPL) is defined as the loss of two or more pregnancies, affecting approximately 1 to 3% of women worldwide. Scientific data highlight a possible correlation between thrombophilic genetic variants and RPL. H1299R variant in the factor V gene would lead to an increased thrombotic risk associated with frequent miscarriages. However, the data are often conflicting, making this an interesting question for further investigations by evaluating genotype-phenotype correlations to improve the clinical management and genetic counseling of couples. A systematic review and meta-analysis will follow the preferred reporting elements for systematic review and meta-analysis protocols (PRISMA-P). The Pubmed (MEDLINE) and Embase (OVID) databases will be explored to identify suitable articles based on inclusion and exclusion criteria. Inclusion criteria are: (a) H1299R genotyping with clear data reported, referred to as Heterozygous (Het) and/or Homozygous (Hom); (b) articles written in English; (c) analyses of only RPL female patients having at least two or more previous pregnancy losses and compared with a control group. This analysis will present selected scientific evidence, addressing the questions concerning the association between the H1299R variant and RPL, hoping to clarify this still unresolved issue. PROSPERO registration number: CRD42022330077.

The Prognostic Value of Pentraxin-3 in COVID-19 Patients: A Systematic Review and Meta-Analysis of Mortality Incidence

“…The quality of eligible records described in this systematic review was individually evaluated by two reviewers (APC and AA) using the Newcastle Ottawa scale (NOS; see Supplementary Table S1 ) as previously described [ 25 , 26 ]. Based on this judgment, the study’s value was classified as low, medium, or high.…”

A Systematic Review and Meta-Analysis of the Association between the FV H1299R Variant and the Risk of Recurrent Pregnancy Loss

“…The protocol of this study has been recorded in the PROSPERO register (CRD42022330077) and has already been published [ 12 ]. Systematic research followed the guidelines of Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) and MOOSE.…”

“…APC and AA performed a bibliographic search using MEDLINE (PubMed) and EMBASE (Ovid) databases according to the eligibility criteria summarized in Table 1 , and specific keywords as previously indicated [ 12 ].…”

“…The heterogeneity was originally evaluated through a graphical examination of the forest plots and then assessed using the I 2 statistic as previously described [ 12 ]. Subgroup analyses were conducted to investigate the influence of the geographical area, mean age of RPL patients, and minimum previous pregnancies losses.…”

“…In the first step, we identified 7391 records using the two databases PubMed (MEDLINE) and Embase (OVID). For this purpose, Medical Subject Headings (MeSH) referring to the thrombophilic variant H1299R and RPL were used as previously illustrated in the study protocol [ 12 ]. Five further records were obtained from additional sources.…”