A prospective, randomized, cross-over comparison of two methods of artificial insemination by donor on the incidence of conception: intracervical insemination by straw versus cervical cap

In a prospective, randomized study of insemination with donor semen,intracervical insemination by straw was compared with insemination using acervical cap with an intracervical reservoir. A total of 91 patientscompleted 486 treatment cycles. There were no significant differences inage, parity, indication for insemination by donor, or method of cyclemonitoring between women who became pregnant and those who did not conceivewith either insemination method. In 236 standard intracervical inseminationcycles, 14 patients became pregnant (5.9% per cycle), whereas 38 patientsconceived in 250 cervical cap cycles (15.2% per cycle). Both the crudepregnancy rates and the cumulative pregnancy rates calculated by theKaplan-Meier life-table method were significantly different (chi(2)-test, P< 0.001, and log-rank test, P < 0.005 respectively). Pregnancy ratesin artificial insemination with cryopreserved donor semen may be improvedby the use of a cervical cap when compared to cervical insemination bystraw. The use of the cervical cap may prolong the exposure of thespermatozoa to the cervical mucus and prevent the backflow of semen intothe vagina.