The Relationship between Gender and Aneuploidy Rates in Patients Undergoing In Vitro Fertilization (IVF) for Sex Selection

BackgroundRecent literature suggests possible gender specific differences in aneuploidy in patients undergoing preimplantation genetic screening (PGS). No data exists on gender specific aneuploidy in patients undergoing PGS for sex selection.Objective(s)To assess the relationship between embryo gender and aneuploidy rates in patients undergoing IVF for sex selection. In addition, to evaluate gender specific differences in blastulation rates (BR) and aneuploid blastocyst rates (ABR) in sex-selected groups.DesignHistorical cohort study.Materials and Method(s)A total of 846 embryos from 97 IVF cycles undergoing sex selection were studied. Patients undergoing PGS with both microarray-based comparative genomic hybridization (aCGH) and fluorescent in-situ hybridization (FISH) were included. There were 467 (55%) embryos in female sex-selected group and 379 (45%) in male sex-selected group. Embryo biopsies were performed on day 3. Aneuploidy rates (AR), blastulation rates (BR), and aneuploid blastocyst rates (ABR) were calculated for each gender. AR was the ratio of abnormal embryos per total embryos biopsied for each gender. BR was the ratio of total blastocysts per day 3 embryos. ABR was the ratio of abnormal blastocysts per total blastocysts for each gender. The logit of the rates were then compared between genders for each sex-selected group using paired t-test.Result(s)For female sex-selected group, there was no difference in overall male and female embryos (0.48 v 0.52), yet more male embryos were noted in male sex selection group (0.55 v 0.45, p=0.04). For patients undergoing female sex selection, there was no statistically significant difference in female or male aneuploidy, blastulation, and aneuploid blastocyst rates (Table 1). Similar results were noted in the male sex-selected group (Table 1). Interestingly, both sex-selected groups demonstrated a 10% increase in aneuploid blastocyst rates in the corresponding gender being selected; however the difference was not statistically significant.Conclusion(s)Our study suggests that the rates of whole chromosomal abnormalities are not different between genders in patients undergoing IVF for sex selection. One still cannot rule out, however, the contribution of other genetic abnormalities not detected by our PGS technology. Larger populations are needed to further evaluate the significance of the gender-specific 10% increase in aneuploid blastocysts seen in our study.SupportNone.Table 1Summary of gender differences in both male and female sex selection groupsFemale Sex selectionMale embryoFemale embryop valueEmbryo sex (number)225 (225/467=0.48)242 (242/467=0.52)0.43Aneuploidy rate (AR)0.420.490.45Blastulation Rate0.260.230.44% abnormal blast0.360.460.32Male Sex SelectionMale embryoFemale embryoP valueEmbryo sex209 (209/379=0.55)170 (170/379=0.45)0.04Abnormal rate0.520.550.7Blastulation rate0.320.250.22% abn blast0.490.40.41 Open table in a new tab BackgroundRecent literature suggests possible gender specific differences in aneuploidy in patients undergoing preimplantation genetic screening (PGS). No data exists on gender specific aneuploidy in patients undergoing PGS for sex selection. Recent literature suggests possible gender specific differences in aneuploidy in patients undergoing preimplantation genetic screening (PGS). No data exists on gender specific aneuploidy in patients undergoing PGS for sex selection. Objective(s)To assess the relationship between embryo gender and aneuploidy rates in patients undergoing IVF for sex selection. In addition, to evaluate gender specific differences in blastulation rates (BR) and aneuploid blastocyst rates (ABR) in sex-selected groups. To assess the relationship between embryo gender and aneuploidy rates in patients undergoing IVF for sex selection. In addition, to evaluate gender specific differences in blastulation rates (BR) and aneuploid blastocyst rates (ABR) in sex-selected groups. DesignHistorical cohort study. Historical cohort study. Materials and Method(s)A total of 846 embryos from 97 IVF cycles undergoing sex selection were studied. Patients undergoing PGS with both microarray-based comparative genomic hybridization (aCGH) and fluorescent in-situ hybridization (FISH) were included. There were 467 (55%) embryos in female sex-selected group and 379 (45%) in male sex-selected group. Embryo biopsies were performed on day 3. Aneuploidy rates (AR), blastulation rates (BR), and aneuploid blastocyst rates (ABR) were calculated for each gender. AR was the ratio of abnormal embryos per total embryos biopsied for each gender. BR was the ratio of total blastocysts per day 3 embryos. ABR was the ratio of abnormal blastocysts per total blastocysts for each gender. The logit of the rates were then compared between genders for each sex-selected group using paired t-test. A total of 846 embryos from 97 IVF cycles undergoing sex selection were studied. Patients undergoing PGS with both microarray-based comparative genomic hybridization (aCGH) and fluorescent in-situ hybridization (FISH) were included. There were 467 (55%) embryos in female sex-selected group and 379 (45%) in male sex-selected group. Embryo biopsies were performed on day 3. Aneuploidy rates (AR), blastulation rates (BR), and aneuploid blastocyst rates (ABR) were calculated for each gender. AR was the ratio of abnormal embryos per total embryos biopsied for each gender. BR was the ratio of total blastocysts per day 3 embryos. ABR was the ratio of abnormal blastocysts per total blastocysts for each gender. The logit of the rates were then compared between genders for each sex-selected group using paired t-test. Result(s)For female sex-selected group, there was no difference in overall male and female embryos (0.48 v 0.52), yet more male embryos were noted in male sex selection group (0.55 v 0.45, p=0.04). For patients undergoing female sex selection, there was no statistically significant difference in female or male aneuploidy, blastulation, and aneuploid blastocyst rates (Table 1). Similar results were noted in the male sex-selected group (Table 1). Interestingly, both sex-selected groups demonstrated a 10% increase in aneuploid blastocyst rates in the corresponding gender being selected; however the difference was not statistically significant. For female sex-selected group, there was no difference in overall male and female embryos (0.48 v 0.52), yet more male embryos were noted in male sex selection group (0.55 v 0.45, p=0.04). For patients undergoing female sex selection, there was no statistically significant difference in female or male aneuploidy, blastulation, and aneuploid blastocyst rates (Table 1). Similar results were noted in the male sex-selected group (Table 1). Interestingly, both sex-selected groups demonstrated a 10% increase in aneuploid blastocyst rates in the corresponding gender being selected; however the difference was not statistically significant. Conclusion(s)Our study suggests that the rates of whole chromosomal abnormalities are not different between genders in patients undergoing IVF for sex selection. One still cannot rule out, however, the contribution of other genetic abnormalities not detected by our PGS technology. Larger populations are needed to further evaluate the significance of the gender-specific 10% increase in aneuploid blastocysts seen in our study. Our study suggests that the rates of whole chromosomal abnormalities are not different between genders in patients undergoing IVF for sex selection. One still cannot rule out, however, the contribution of other genetic abnormalities not detected by our PGS technology. Larger populations are needed to further evaluate the significance of the gender-specific 10% increase in aneuploid blastocysts seen in our study.