Maternal IVS1-401 T allele of the estrogen receptor alpha is an independent predictor of late fetal loss.

OBJECTIVE: To investigate whether sequence variants in the gene encoding for estrogen receptor alpha (ER-alpha) are risk determinants for fetal loss. DESIGN: Case-control study. SETTING: University medical center. PATIENT(S): One hundred four women with a history of fetal loss and 277 healthy women with at least one previous pregnancy and no previous fetal loss. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): The IVS1-401C/T polymorphism of the human ER-alpha, the G1691A mutation of the factor V gene (factor V Leiden), the G20210A mutation of the prothrombin gene, and the C677T polymorphism of the methylenetetrahydrofolate-reductase (MTHFR) gene were determined by polymerase chain reaction. RESULT(S): In the subgroup analysis of women with at least one late miscarriage (n = 70), the prevalences of the ER-alpha IVS1-401 T allele (T/T vs. C/C, odds ratio [OR]: 2.85, P=.018; T/T + C/T vs. C/C, OR: 2.28, P=.043) and of heterozygous factor V Leiden (OR, 3.2; P=.002) were significantly higher among women with late fetal loss than among healthy women. Carriers of both risk determinants have an at-least additive increase in risk for late abortions (OR, 7.0; P=.0004). The population of all late abortions that would be attributable to the genetic variants (population attributable risk) was 13.9% for factor V Leiden and 49.2% for the ER-alpha IVS1-401 T allele. CONCLUSION(S): Women with the IVS1-401 T allele of the ER-alpha and/or factor V Leiden are at increased risk for late fetal loss.

The polymorphism of platelet membrane integrin alpha2beta1 (alpha2807TT) is associated with premature onset of fetal loss.

Inherited thrombophilia could increase susceptibility to adverse pregnancy outcomes such as fetal loss. We determined the G1691A mutation of the factorV gene (FVL), the G20210A mutation of the prothrombin gene, the C677T polymorphism of the methylenetetrahydrofolate-reductase (MTHFR) gene, the HPA-1 polymorphism of the beta3 subunit of the platelet integrin alphaIIbbeta3 and the C807T polymorphism of the alpha2 subunit of integrin alpha2beta1 in 104 women with fetal loss and 277 normal women. In a subgroup analysis of women with recurrent early fetal loss (n=34), the prevalence of the genetic markers did not differ significantly between the women with early fetal loss and the normal women. However, in this subgroup of patients the onset of fetal loss was significantly earlier in women with the alpha2807TT genotype (7.1 +/- 1.9 vs. 8.8 +/- 1.5 weeks, p=0.001). No such significant difference was observed in carriers of the other genetic markers. In the subgroup analysis of women with late fetal loss (n=70), only the prevalence of heterozygous FVL was significantly associated with late fetal loss (odds ratio 3.2, p=0.002). There was no significant association of any genetic risk factor with premature fetal loss in the subgroup analysis of women with at least one late miscarriage. This study demonstrates a significant association of the alpha2807TT genotype of the platelet membrane integrin alpha2beta1 with premature onset of early fetal loss. It appears that this risk factor does not induce the pathomechanism, but modulates the course of fetal loss. Furthermore, our study confirms the association of FVL with late fetal loss.