Importance of embryo transfer duration in human assisted reproduction techniques

The most important step in in vitro fertilization (IVF) is the transfer of the embryos (ET) in the uterine cavity. Stimulation of the cervix or uterus during the procedure causes uterine contractions and possibly expulsion of the embryos. The catheter for embryo transfer can also be an element of local distress. The aim of the present pilot study was to assess the influence of the time the catheter remains inside in the uterine cavity on the final outcome of the IVF procedure. The prospective two-center study excluded patients with difficult ET procedure. The pregnancy was confirmed by ultrasound (embryonic cardiac activity present) 6 weeks after the procedure. Patients were divided into two groups (catheterization < 120 seconds or > 120 seconds). Data were processed and statistically analyzed applying Fisher's exact test. 122 cycles of IVF were analyzed. Average ages of patients included in the study was 34.6 years, the average number of transferred embryos was 2.18 and 36 % of the patients achieved a clinical pregnancy (29% of group A and 43% of group B). The statistical analysis indicated no significant differences between the two groups in term of pregnancy rate ( p>0.05).