6 8. Sperm Preparation Methods The aim of semen preparation is to separate motile, mor- phologically normal spermatozoa from the seminal plasma and from debris such as leucocytes, bacteria, and nonmotile spermatozoa. Table 2 shows studies that addressed the eﬀect of diﬀerent sperm preparation methods on IUI outcome. As shown in the table, the number of these studies is limited. Sperm wash, swim-up, and density gradient centrifugation are the most commonly used methods. As shown in Table 2, density gradient centrifugation was associated with acceptable IUI outcomes [58–62]. Swim-up as a procedure is also associated with satisfactory IUI outcomes, comparable to density gradient centrifugation pregnancy rates. Further- more, other studies (the preparation technique was not the primary question addressed) reported similar outcomes for both methods [47, 50]. Boomsma et al. conducted a Cochrane review to compare the eﬀectiveness of the three diﬀerent semen preparation techniques (conventional wash, swim-up procedure, and density gradient centrifugation) before IUI [63]. Only two RCTs could be included in the meta-analysis regarding the clinical outcomes. This resulted in insuﬃcient data to recommend anyone of the three semen preparation techniques over the others. The time intervals between semen collection, sperm processing, and insemination may aﬀect IUI outcomes. Yavas and Selub performed a retrospective study where the collection of semen at the clinic was found to be better than at home. Short intervals from semen collection to sperm wash, from sperm wash to IUI, and from semen collection to IUI were associated with higher pregnancy rates compared to semen collection at home with longer time intervals [64]. Considerations in Technology-Limited Settings. The evidence suggests that conventional sperm wash for IUI can be used in a low-technology setting. The evidence does not seem to show that anyone of the three commonly used sperm preparation methods results in a higher pregnancy rate than any other. 9. Timing of IUI Normal sperm is capable of fertilizing an oocyte in the female genital tract for about 5 days, and an oocyte is fertilizable for 12–24 hours after ovulation [65]. The WHO conducted a large multicenter study that concluded that ovulation occurred between 24 and 56 hours (average 32 hours) after the onset of luteinizig hormone (LH) surge [66]. In another study ovulation, occurred 36–38 hours after the onset of LH surge in natural cycles [67]. The LH surge can be detected at home using urinary LH kits. The monitoring for the urinary LH surge can start about 3 days before the expected date of ovulation. Generally, in natural cycles, IUI can be performed 24 hours after the onset of LH surge as detected by urinary LH monitoring. In controlled ovarian stimulation cycles in which ovu- lation is triggered artiﬁcially, ovulation occurs 32–38 hours after human chorionic gonadotropin (HCG) injection [68, Obstetrics and Gynecology International 69]. Based on the available data about the timing of ovu- lation, some investigators recommended that insemination can be carried out between 12 and 60 hours after HCG injection [70–72]. Other investigators found that delayed inseminations to 38–40 hours after HCG injection were associated with higher pregnancy rates compared to early inseminations [73]. This was not found in a study by Claman et al., who found that there was no signiﬁcant diﬀerence in pregnancy rates between early (32–34 hours) and late (38–40 hours) inseminations [74]. When HCG is used, insemination can be done 34–40 hours after injection [75]. A systematic review was performed by Kosmas et al. to compare the eﬀectiveness of HCG administration versus urinary LH detection as a method of IUI timing after CC stimulation [76]. Seven studies were included in this systematic review and the meta-analysis. The authors found that the use of urinary LH monitoring as a method of IUI timing was associated with higher pregnancy rates than the HCG administration method. They concluded that LH monitoring for IUI timing is more practical, eﬀective, and cost-eﬀective when CC is used for ovarian stimulation [76]. Considerations in Technology-Limited Settings. The evidence suggests that it is reasonable to perform IUI, for either natural cycle IUI or for clomiphene combined with IUI, approximately 24 hours after the detection of the LH surge. Urine testing kits could be used to detect the LH surge. 10. Number of Inseminations per Cycle Several studies have compared single versus double IUIs in an ovulatory cycle. One of the earlier studies, conducted for that purpose, reported a cycle fecundity of 52% when 2 inseminations 18 and 42 hours after HCG were performed while a single insemination performed 34 hours after HCG injection resulted in a cycle fecundity of 8.7% [71]. Another study found that double inseminations, performed 12 and 34 hours after HCG administration, in gonadotropin stimulated cycles, resulted in a pregnancy rate per patient of 30.4%, a higher pregnancy rate than that found from single inseminations (14.4%) performed 34 hours after HCG [72]. On the other hand, Ransom et al. found no diﬀerence in pregnancy rates between single IUI performed 35 hours after HCG and double IUI done 19 and 43 hours after HCG injection [77]. These results were supported in a study by Alborzi et al. [78] where pregnancy rates per cycle were 8.6% and 9.4% (nonsigniﬁcantly diﬀerent) for single and double IUIs. Another study, by Casadei et al., failed to show a signiﬁcant advantage of double inseminations 12 and 36 hours after HCG injection over single insemination done 36 hours after HCG [79]. Two reviews were conducted to reach a conclusion about the number of inseminations per cycle [80]. One was a systematic review and meta-analysis [80] and the second was a Cochrane analysis [81]. In the ﬁrst review, by Osuna et al., 18 trials were retrieved from searching Medline, The Cochrane library, and the abstract books of annual meetings of ESHRE and ASRM [80]. Only six randomized prospective