Risk of placenta-mediated pregnancy complications or pregnancy-related VTE in VTE-asymptomatic families of probands with VTE and heterozygosity for factor V Leiden or G20210 prothrombin mutation.
BACKGROUND
Few studies have evaluated the risk of pregnancy-related adverse events in asymptomatic relatives of probands for VTE and factor V Leiden or the G20210A variant. The antepartum management of this population ranges from antepartum anticoagulation therapy to clinical surveillance.


OBJECTIVE
To evaluate the risk of placenta-mediated pregnancy complications and pregnancy-related VTE in VTE-asymptomatic families of probands with VTE and who are heterozygous carriers of either factor V Leiden or PT-G20210A mutation.


METHODS
One hundred and fifty-eight relatives, who had 415 pregnancies, were retrospectively evaluated. Odds ratios and 95% confidence intervals were calculated to compare pregnancy outcomes between women with and without thrombophilia.


RESULTS
In the factor V Leiden group, 22 placenta-mediated pregnancy events of 152 pregnancies (14.4%) were reported, compared with 25 adverse events of 172 pregnancies in the G20210A prothrombin group (14.5%) and 13 adverse events of 91 pregnancies in the non-carrier group (14.2%). Carriers of factor V Leiden or G20210A prothrombin were not associated with a higher risk of pregnancy-adverse outcomes compared with non-carriers: OR 1.02 (95% CI, 0.40-2.25) and 1.25 (95% CI, 0.48-3.24), respectively. Four episodes of pregnancy-associated VTE of 415 pregnancies (0.96%) were recorded. Two episodes of VTE in the G20210A group, one in the factor V Leiden group, and one episode in the non-carrier group were noted.


CONCLUSIONS
In VTE-asymptomatic relatives of probands with VTE, the presence of factor V Leiden or the G20210A prothrombin mutation in heterozygosis should not lead to a decision to instigate antepartum prophylaxis.
Hematology Department, IBSAL-Hospital Universitario de Salamanca, Salamanca, Spain.
Iris
I
Cordoba
Carlota
C
Pegenaute
Tomás José
TJ
González-López
Carmen
C
Chillon
Maria Eugenia
ME
Sarasquete
Francisco
F
Martin-Herrero
Carmen
C
Guerrero
Mónica
M
Cabrero
Maria Helena
MH
Garcia Sanchez
Pedro
P
Pabon
Francisco Santiago
FS
Lozano
Marcos
M
Gonzalez
Ignacio
I
Alberca
José Ramón
JR
González-Porras
D005165:Factor V / Q000235:genetics*; D005260:Female; D006579:Heterozygote; D006801:Humans; D009154:Mutation; D010920:Placenta / Q000503:physiopathology*; D011247:Pregnancy; D011250:Pregnancy Complications, Hematologic / Q000235:genetics / Q000503:physiopathology*; D011516:Prothrombin / Q000235:genetics*; D054556:Venous Thromboembolism / Q000150:complications* / Q000235:genetics
C095381:factor V Leiden; D005165:Factor V; D011516:Prothrombin