Elevated serum müllerian-inhibiting substance may be a marker for ovarian hyperstimulation syndrome in normal women undergoing in vitro fertilization.

We identified patients who experienced ovarian hyperstimulation syndrome (OHSS) (n = 16) and compared their baseline pretreatment levels of müllerian-inhibiting substance (MIS) to age- and weight-matched patients with normal responses to gonadotropins (n = 14). Baseline serum MIS in patients with OHSS were sixfold higher than those seen in normal controls (3.62 +/- 0.87 vs. 0.63 +/- 0.09 ng/mL; P=.0036), indicating that MIS could potentially serve as a useful marker for identifying patients at risk for OHSS.