The effect of ejaculatory abstinence time on in vitro fertilization outcomes.

We included all patients having their first autologous oocyte IVF cycle using either standard insemination or intracytoplasmic sperm injection (ICSI) between January 2021 and January 2022 at our academic IVF program. All men received the same instructions about the recommended ejaculatory abstinence before the IVF cycle and then were asked for the actual time of ejaculatory abstinence just before semen collection. Cycles with ejaculatory abstinence periods of 7 days, embryo banking, and frozen or donor sperm were excluded. The included cycles were divided into six groups on the basis of days of ejaculatory abstinence, rounded up in 0.5 days. Semen analysis was performed by trained andrology technologists following the World Health Organization standards ( 1 ). Analysis of variance and x 2 test were used to analyze the relationship between duration of ejaculatory abstinence and outcomes. Logistic regression was performed to adjust for the potential confounder of maternal age for embryo transfer outcomes. A power analysis was performed using a fertilization rate and SD (76 ± 19) ( 2 ). With these assumptions, we had 89.9% power to detect an absolute 7% difference in the fertilization rate with ANOVA, with the α set to 0.05. The study was determined to be exempt from review by the Institutional Review Board (IRB 201709794) at our center.

Emily Capper: Writing – review & editing, Writing – original draft, Visualization, Project administration, Methodology, Conceptualization. Karen Summers: Writing – review & editing, Visualization, Methodology, Formal analysis, Data curation. Amy Sparks: Writing – review & editing, Supervision, Data curation. Emily Jacobs: Writing – review & editing, Supervision, Conceptualization. Bradley Van Voorhis: Writing – review & editing, Visualization, Supervision, Project administration, Methodology, Conceptualization.

A total of 541 couples were retained for analysis. Standard insemination was used in 44% of couples, whereas 56% of couples underwent ICSI insemination. There was no difference in baseline characteristics by days of ejaculatory abstinence ( Table 1 ). Table 1 Patient demographics and baseline data by days of ejaculatory abstinence. EA days 2 3 4 5 6 7 Full sample P n 47 150 157 107 39 41 541 Female age (y) 34.3 ± 4.4 33.5 ± 4.4 33.4 ± 4.4 33.9 ± 4.5 32.3 ± 4.9 34.0 ± 3.7 33.6 ± 4.4 .31 Male age (y) 35.6 ± 5.6 35.2 ± 5.5 35.1 ± 5.4 35.5 ± 5.4 35.3 ± 5.4 35.6 ± 5.1 35.3 ± 5.7 .99 Female BMI (kg/m 2 ) 29.1 ± 6.3 29.1 ± 7.7 29.3 ± 6.9 29.8 ± 7.6 31.4 ± 8.4 32.2 ± 7.4 29.7 ± 7.4 .14 Female White race 41 (87%) 130 (88%) 138 (88%) 100 (94%) 31 (82%) 34 (83%) 474 (88%) Female gravidity 1 (0, 2) 0 (0, 2) 1 (0, 2) 0 (0, 2) 0 (0, 2) 1 (0, 2) 0 (0, 2) .499 Female parity 0 (0, 1) 0 (0, 1) 0 (0, 1) 0 (0, 0) 0 (0, 0) 0 (0, 1) 0 (0, 1) .862 Diagnoses a  Male factor 12 (26%) 44 (29%) 43 (28%) 33 (31%) 12 (31%) 10 (24%) 154 (29%) .959  Ovulatory dysfunction 12 (26%) 32 (21%) 32 (21%) 26 (24%) 9 (23%) 10 (24%) 121 (22%) .962  Endometriosis 3 (6%) 21 (14%) 23 (15%) 20 (19%) 9 (23%) 4 (10%) 80 (15%) .225  Tubal factor 14 (30%) 32 (21%) 24 (15%) 18 (17%) 11 (28%) 11 (27%) 110 (20%) .135  Unexplained 11 (23%) 40 (27%) 37 (24%) 17 (16%) 6 (15%) 5 (12%) 116 (22%) .162  Other b 11 (23%) 31 (21%) 34 (22%) 32 (30%) 8 (21%) 12 (29%) 128 (24%) .502 No. of oocytes retrieved 16.1 ± 9.6 16.0 ± 9.7 15.7 ± 9.4 15.8 ± 11.0 15.1 ± 8.7 15.5 ± 7.9 15.8 ± 9.6 .99 Note: Data presented as means ± SDs, medians (interquartile ranges), or frequencies (%). BMI = body mass index; EA = ejaculatory abstinence. a Patients may have multiple diagnoses; therefore, the sum of diagnosis category percentages may be >100. b Diagnoses in <10% of sample reported as “other” included diminished ovarian reserve, advanced maternal age, uterine factor, and recurrent pregnancy loss. Patient demographics and baseline data by days of ejaculatory abstinence. Note: Data presented as means ± SDs, medians (interquartile ranges), or frequencies (%). BMI = body mass index; EA = ejaculatory abstinence. Patients may have multiple diagnoses; therefore, the sum of diagnosis category percentages may be >100. Diagnoses in <10% of sample reported as “other” included diminished ovarian reserve, advanced maternal age, uterine factor, and recurrent pregnancy loss. An increase in the days of ejaculatory abstinence was associated with improved semen analysis parameters including semen volume, sperm concentration, and total motile sperm count but not sperm motility ( Table 2 ). Despite higher semen analysis parameters with longer ejaculatory abstinence up to 7 days, there was no effect of increasing ejaculatory abstinence on either ICSI or standard insemination fertilization rates. There were also no significant differences in the clinical pregnancy, live birth, and miscarriage rates with increasing time of ejaculatory abstinence ( Table 2 ). Table 2 Semen parameters (mean ± SD) and in vitro fertilization outcomes by days of ejaculatory abstinence. EA days 2 3 4 5 6 7 Increase per additional day n 47 150 157 107 39 41 Semen volume (mL) 2.6 ± 1.1 3.0 ± 1.5 3.1 ± 1.5 3.4 ± 1.6 3.5 ± 2.1 3.9 ± 1.9 0.2 (0.1–0.3) Semen concentration (×10 6 ) 47.4 ± 33.3 44.1 ± 43.0 50.6 ± 39.0 62.6 ± 63.4 82.8 ± 70.8 78.0 ± 103.8 8.5 (5.0–11.9) Sperm motility (total) 46.5 ± 15.5 46.5 ± 16.7 47.8 ± 14.6 47.6 ± 16.6 48.1 ± 14.1 50.5 ± 16.7 0.70 (−0.30 to 1.69) Total motile sperm count (×10 6 ) 59.2 ± 58.2 66.8 ± 73.1 79.7 ± 79.2 100.2 ± 122.9 135.4 ± 155.9 136.9 ± 122.8 17.6 (11.5–23.8) Standard insemination fertilization rate (mean ± SD) n 22 60 70 49 18 17 Fertilization rate 74.8 ± 18.6 71.7 ± 21.0 68.7 ± 20.8 72.0 ± 20.4 78.7 ± 15.6 73.3 ± 19.1 3.2 (−24.5 to 30.9) ICSI fertilization rate (mean ± SD) n 25 89 86 57 21 24 Fertilization rate 75.9 ± 22.5 75.3 ± 18.0 75.2 ± 19.7 74.6 ± 18.9 75.2 ± 15.3 75.0 ± 17.5 2.3 (−19.1 to 23.7) Embryo transfer outcomes, n (%) n 44 132 143 90 39 34 AOR Live birth 26 (59) 69 (52) 64 (45) 35 (39) 20 (41) 19 (56) 0.94 (0.82–1.08) Clinical pregnancy 27 (61) 83 (63) 80 (56) 49 (54) 26 (67) 22 (65) 1.00 (0.87–1.15) Miscarriage 0/27 (0) 14/83 (17) 16/80 (20) 12/49 (25) 5/26 (19) 3/22 (14) 1.16 (0.93–1.44) Note: AOR = adjusted odds ratio; EA = ejaculatory abstinence; ICSI = intracytoplasmic sperm injection. Semen parameters (mean ± SD) and in vitro fertilization outcomes by days of ejaculatory abstinence. Note: AOR = adjusted odds ratio; EA = ejaculatory abstinence; ICSI = intracytoplasmic sperm injection.

Performing a semen analysis is a cornerstone to the evaluation of infertility. The World Health Organization recommends 2–7 days of ejaculatory abstinence before semen collection for diagnostic purposes, whereas the European Society of Human Reproduction and Embryology advises 3–4 days of ejaculatory abstinence. If variation in ejaculatory abstinence affects semen analysis results, this could influence whether a male is diagnosed with having a problem needing further evaluation. Obtaining a semen sample is an essential part of infertility treatments including intrauterine inseminations and in vitro fertilization (IVF). In clinical practice, advice regarding ejaculatory abstinence before testing has been extrapolated from diagnostic ejaculatory abstinence recommendations. A common question from men trying to improve their IVF outcomes is as follows: what number of ejaculatory abstinence days is optimal? Is there a difference within this range of 5 days? To answer this, we investigated semen parameters, sperm function via the fertilization rate, and the live birth in patients undergoing IVF with an ejaculatory abstinence period varying between 2 and 7 days.

Our findings of significantly improved semen parameters with increased ejaculatory abstinence, even within the World Health Organization recommended range for diagnostic purposes, agree with prior studies ( 2 , 3 , 4 ). This should be considered when evaluating semen analysis results and may explain some of the known variation in semen analysis results in an individual. We found no significant effect of increasing days of ejaculatory abstinence on sperm function on the basis of the fertilization rate and IVF pregnancy rates after either standard insemination or ICSI, which has not been previously reported. Thus, patients can be advised that there is no optimal ejaculatory abstinence within this recommended window of time (2–7 days) for IVF outcomes. Further research is needed to more fully evaluate the effect of even shorter ejaculatory abstinence times on IVF outcomes given the recent finding that <4 hours of ejaculatory abstinence is associated with better semen quality ( 5 ).

E.C. has nothing to disclose. K.S. reports payments for statistical consulting on Society for Assisted Reproductive Technology database outside the submitted work. A.S. has nothing to disclose. E.J. has nothing to disclose. B.V.V. has nothing to disclose.