In Sweden a study was done by Prof C. Linde-Forsberg (Faculty of Veterinary Medicine, Department of Obstetrics and Gynaecology, Swedish University of Agricultural Science, Uppsula Sweden) i which the conception rate and the litter size were examined with the use of fresh, chilled and frozen semen using vaginal as well as transcervical insemination.
The results are as follows (from 2041 inseminations):
| Semen Type | conception % with vaginal insemination | conception % with transervisal insemination |
| Fresh | 47.8 | 65.2 |
| Chilled | 45.1 | 65.6 |
| Frozen | 34,6 | 52.0 |
| Semen Type | Average litter size % vaginal insemination | Average litter size % transcervical insemination |
| Fresh | 5.8 +/- 2.8 pups | 6.5 +/- pups |
| Chilled | 5.8 +/- 3.0 pups | 6.4 +/- pups |
| Frozen | 4.7 +/- 2.6 pups | 5.0 +/- pups |
Reference: Professor C. Linde –Forsberg. Intra-Uterine Insemination in the Dog Using the Scandinavian Trans-Cervical Catheter and a Comparison with other Methods. Sciences, Uppsala, Sweden. Publisher: Recent Advances in Small Animal Reproduction P. W. Concannon, G. England and J. Verstegen (Eds.). 02.02.2001. International Veterinary Information Service (www.ivis.org), Ithaca, New York, USA.