Fetal syphilis in the first trimester.

Evidenc of first-trimester fetal syphilis was sought in the products of conception in a therapeutic abortion clinic. During two collection periods of one week, five patients with serologic and clinical data consistent with recent syphilitic infection were identified. Their conceptuses were carefully examined by silver and immunofluorescent stains for the presence of Treponema pallidum. Two of these five conceptuses (9 and 10 weeks' gestation) were found to contain T. pallidum by these methods. The literature supporting the Langhans layer/five months' placental barrier theory is reviewed and discussed in view of these two first-trimester cases.