Blood anti-Müllerian hormone is a possible determinant of recurrent early miscarriage, yet not conclusive in predicting a further miscarriage.

ABSTRACT

RESEARCH QUESTION Is blood anti-Müllerian hormone (AMH) concentration a strong determinant of unexplained recurrent early miscarriage (REM)? DESIGN: In the first part of the study, AMH concentrations measured using an Immunotech ELISA Kit were compared between 188 unselected (mostly fertile) women consecutively referred for three or more miscarriages in the first trimester of pregnancy and 376 age-matched parous women without pregnancy loss. Cases and controls were previously enrolled in an incident case-control study on thrombophilic mutations. Blood samples were collected >2 months after any recognized obstetric event or hormonal treatment. In the second part of the study, a prospective 2-year follow-up of cases was performed. RESULTS: When considering all women irrespective of age, AMH concentration did not significantly differ between cases and controls. However, in the subgroup ≥25 years old (176 cases versus 358 controls of ∼33.5 years), the cases had significantly lower AMH concentrations than the controls (median [interquartile range] 2.8 [1.4-4.7] versus 3.25 [1.7-5.5], P = 0.046) and the proportion of cases with an AMH concentration <1 ng/ml was significantly higher (17.6% versus 10.6%; odds ratio 1.80; 95% confidence interval 1.07-3.00, P = 0.028). With regard to the subsequent pregnancy, AMH concentration was not correlated with either the conception delay or the miscarriage occurrence. However, increased age and number of previous miscarriages were significantly predictive of a subsequent miscarriage (P = 0.046 and 0.03, respectively). CONCLUSION: An altered ovarian reserve is a possible determinant of unexplained REM. However, AMH blood concentration predicts neither the delay nor the outcome of a subsequent pregnancy.