THE EFFECT OF HALVING THE STANDARD-DOSE OF CRYOPRESERVED SEMEN FOR DONOR INSEMINATION - A CONTROLLED-STUDY OF CONCEPTION RATES

Employing a common standard technique of intra-cervical insemination f rom straws of cryopreserved donor semen, a volume of 0.25 ml of 0.5 ml was inseminated in alternate cycles to determine if the lower volume could be used without a decrease in the conception rate. A total of 17 7 women were recruited and received a median of four cycles of treatme nt. Of these, 90 women became pregnant, 47 with 0.5 ml and 43 with 0.2 5 ml inseminations. The conception rates were identical for both volum es in the first nine cycles of treatment and the cumulative rates were 57.7 and 59.3%, respectively. Subsequently more pregnancies were achi eved with 0.5 ml than 0.25 ml semen (nine pregnancies in 73 further cy cles versus three pregnancies in 68 cycles, respectively), although th e difference was not statistically significant. There were no signific ant differences in the women's ages, luteinizing hormone, follicle sti mulating hormone, progesterone, mucus quality, mucus pH, parity or par tner's diagnosis between those women who became pregnant and those who failed to conceive with either insemination dose. We conclude that th e volume of semen inseminated into the cervical canal without a cervic al cap can be decreased to 0.25 ml without an adverse effect on the co nception rate at least in the first 9 months of treatment. This will a llow more effective use to be made of valuable screened and quarantine d cryopreserved semen.