Ovarian stimulated cycle: not a better alternative for women without ovulation disorder in intrauterine insemination

To explore the related factors on the clinical pregnancy outcome in intrauterine insemination, a retrospective study was conducted on the clinical data of 580 cycles for 301 infertile couples who were treated with intrauterine insemination. The female age, male age, duration of infertility, treatment protocols, endometrial thickness and sperm parameters were compared between pregnant group and non-pregnant group. The results showed that there were statistical differences in female age, duration of infertility and endometrial thickness between the two groups. The pregnancy rate was 19.34% in Group A (female age ≤ 30 y) compared with 10.91% in Group B (female age > 30 y). The pregnancy rate was 18.44% when the duration of infertility ≤ 2 years, which was higher than another group 10.73% when the duration of infertility > 2 years. Group analysis according to endometrial thickness (Group1: < 8 mm; Group 2: ≥ 8 mm and ≤ 12 mm; Group 3: > 12 mm) demonstrated significant differences in clinical pregnancy rate (7.41%, 18.00% and 11.48% respectively). For those infertile female without ovulation failure, the higher clinical pregnancy rates were observed in patients undergoing intrauterine insemination in natural cycle 16.12% when compared with the patients in ovarian stimulated cycles 10.48%. Thus, we demonstrate that the pregnancy rate is related with female age, duration of infertility and endometrial thickness. The ovarian stimulated cycle couldn't improve the pregnancy outcome for those women without ovulation disorder in intrauterine insemination.