Novel uterine lavage system for recovery of human embryos fertilized and matured in vivo

Abstract

Purpose: In this paper we describe a novel uterine lavage system for the recovery of in vivo preimplantation embryos. Currently, no other method exists to retrieve preimplantation embryos except for in vitro fertilization (IVF).

Methods: A single center, prospective feasibility study was conducted to test a novel uterine lavage system for the recovery of in vivo preimplantation embryos in egg donors and patients seeking pregnancy. Subjects were placed on controlled ovarian hyperstimulation followed by intrauterine insemination (IUI) and uterine lavage performed approximately 4–6 days after IUI. Subjects were followed up for 30 days after the procedure to monitor for safety events.

Results: A total of 134 uterine lavage cycles were performed on 81 subjects (average: 1.7 cycles/subject). Ova (oocytes or embryos) were collected in 53% (71/134) of the cycles with steady improvement of recovery efficiency over the course of the study, and embryos collected in 42% (56/134) of cycles. Embryos of many stages were collected, but 71% (96/136) of embryos collected were blastocyst stage embryos which are at the most advanced stage of embryogenesis. Embryos recovered were of good quality based on blastocyst gradings in which 74% (70/95, 1 blastocyst not graded) of the blastocysts were good quality as determined by the Gardner Scale of Morphology. The procedure was well tolerated with minor side effects. In 8% of cycles a positive hCG was observed after the lavage indicating some embryos were not recovered by the lavage system.

Conclusion: Through this work the system has been shown to recover embryos from the uterus in a safe and effective manner, thus opening the possibility that uterine lavage may serve as an alternative to IVF where patient indications allow.

Keywords:

• in vivo embryo
• uterine lavage
• IVF
• assisted reproductive technology
• blastocyst

Acknowledgment

All funding provided by Previvo Genetics, Inc.

Ethics approval

The work described in this paper was performed at the Punta Mita Hospital in Punta Mita, Mexico. The study received Institutional Review Board (IRB) approval from Western IRB (Puyallup, WA, USA) and local Mexican government approval from Servicios de Salud de Nayarit (Tepic, Mexico). The study is currently registered on clinicaltrials.gov (NCT03426007) and has been performed in accordance with the Declaration of Helsinki.

Informed consent

Written informed consent was received from all subjects in which subjects acknowledged the benefits/risks of the study and agreed to the publication of de-identified study data gathered through their participation.

Data sharing statement

The authors do not intend to share any further de-identified participant data.

Disclosure

Alexander Nadal declares he is a salaried employee of Previvo Genetics, and holds stock options in Previvo Genetics. Dr. Sam Najmabadi declares that he holds shares of Previvo Genetics, and was provided funding to perform this study by Previvo Genetics. Bruce Addis declares he is a salaried employee of Previvo Genetics, holds stock options in Previvo Genetics, and is a named co-inventor on a provisional patent application with rights assigned to Previvo Genetics. Dr. John E Buster reports he is a salaried employee of Previvo Genetics, is a member on the Previvo Genetics Board of Directors and Scientific Advisory Board, and holds shares in Previvo Genetics. In addition, Dr. Buster is a named co-inventor on multiple granted patents and patent applications, with all rights assigned to Previvo Genetics. All authors report no other conflicts of interest in this work.