Sex Ratios Of Human Embryos Derived From Sperm Sorted By Albumin Gradient For Gender Enrichment As Determined By Preimplantation Genetic Diagnosis

Authors: David Hill, PhD, Sergei Evsikov, PhD, Mark Surrey, MD, Hal Danzer, MD, and Desta Gelagay, MT(CLS)(ASCP). Beverly Hills, California

Objective: To determine if the sex ratio of embryos derived from X or Y sperm- enriched gradient fractions were different from embryos derived from unselected sperm in IVF cycles using either X-enriched, Y-enriched or unselected sperm for insemination of oocytes.

Design: A retrospective clinical study.

Setting: Private clinic for assisted reproductive technology.

Patients: Thirty-three patients (six were oocyte recipients) undertook 42 IVF cycles for the specific goal of sex identification of their preimplantation embryos.

Interventions: Patients were grouped in three categories according to the type of sperm preparation employed in their IVF cycle: (A) unselected gradient prepared sperm (n = 19), (B) Y-bearing sperm enriched fraction (n = 18), or (C) X-bearing sperm enriched fraction (n = 5).

Main Outcome Measures: Evaluation of chromosomes 13, 18, 21, X and Y by PGD using fluorescent in situ hybridization (FISH).

Results: Two hundred seventy embryos were biopsied end evaluated. The percentage of aneuploid, but sex-determinable embryos was about a third (36, 33 and 30%) for groups A, B and C, respectively. Male:Female sex ratios in these aneuploid embryos were (A) 22:12, (B) 24:19, and (C) 4:3. Embryos balanced for the tested chromosomes were distributed, by sex, as follows: In category A, the male : female ratio was 31: 30, category B was 34 : 32, category C was 5 : 11. Forty-three embryos had an abnormal number of sex chromosomes.

Conclusion: Sex ratios of embryos derived from sperm fractionated by albumin density gradient for the purpose of sex preselection are not significantly different from that of embryos derived from un-preselected sperm preparations as determined by the Chi-squared statistical test.

Key Words: Albumin gradient sperm sex preselection, preimplantation genetic diagnosis, FISH,efficacy, IVF.