The Euro-Lupus regimen of low-dose intravenous cyclophosphamide (IV CYC) (cumulative dose of 3 gm) was developed to reduce gonadal toxicity. To address the possibility of a marginal effect on the ovarian reserve, we measured serum titers of anti-Müllerian hormone (AMH) in patients with systemic lupus erythematosus (SLE) treated with the Euro-Lupus regimen and compared them with those measured in patients who were treated with higher doses of IV CYC or were never treated with IV CYC.
Serum AMH levels were measured by enzyme-linked immunosorbent assay in a cohort of 155 premenopausal SLE patients; 30 of these patients had been treated with the Euro-Lupus regimen, and 24 had received higher doses of IV CYC. None had received oral CYC. AMH levels were age-adjusted using a slope computed from levels measured across the group of SLE patients who had not been treated with IV CYC. Demographic and clinical data were collected.
Serum titers of AMH measured in SLE patients treated with the Euro-Lupus IV CYC regimen (median dose 1.46 ng/ml) did not differ from those measured in patients never treated with the cytotoxic drug (median 1.85 ng/ml). As expected, patients given >6 gm of IV CYC had significantly lower serum titers of AMH (median 0.83 ng/ml) compared with those never treated with IV CYC (P = 0.047). Median serum AMH titers did not change before (1.24 ng/ml) and after (2.50 ng/ml) treatment with the Euro-Lupus IV CYC regimen in the subset of patients for whom paired samples could be tested (P = 0.43).
The Euro-Lupus regimen of low-dose IV CYC does not impact the ovarian reserve of SLE patients and can therefore be proposed as treatment in patients seeking to become pregnant.