Serum CA 125 in a pregnancy generated by ovum donation

: Serum CA 125 was measured by radioimmunoassay during the first trimester at intervals of 2 weeks in a woman with Turner's syndrome, who conceived following ovum donation from a healthy anonymous donor. Serum CA 125 concentrations were lower than or at the 10th percentile of the normal range. These findings imply that CA 125 may be secreted from the ovary in the first trimester, or produced at another site in response to stimuli from the ovary.