OP-IVM: Combining In vitro Maturation after Oocyte Retrieval with Gynecological Surgery

The technology, OP-IVM, is an extension of conventional IVM protocol that combines IVM following oocyte retrieval with routine gynecological surgery. It is suitable for infertile or subfertile women who need to receive gynecological surgery before ART treatment or fertility preservation, polycystic ovary syndrome patients with clomiphene resistance who need a laparoscopic ovarian drilling surgery, infertile patients who are in need of benign gynecologic surgeries such as hysteroscopic myomectomy, polypectomy, transthoracic resection of septum, and the laparoscopic tube surgery, and the oophorocystectomy before ART treatment, and also patients with cancer and hematologic disease who are receiving chemoradiotherapy or radiotherapy, they can do this surgery for fertility preservation. Place the ultrasound probe inside the vagina to scan and record the number of follicles in both ovaries.

Find the location closest to the ovary as the puncture site, avoiding the intestine, bladder, and large blood vessels. Wash the 19 gauge single lumen aspiration needle with a pH stable handling medium, then inject the needle into the ovaries under the guidance of ultrasound. Aspirate follicular fluid with the needle under a pressure of 80 to 90 millimeters of mercury, rotating the needle slightly to aspirate as much follicular fluid as possible.

Use heparin to reduce follicular fluid viscosity during the aspiration. Adjust the probe's position to keep it as close as possible to the ovaries at all times and press the vaginal fornix with the proper force to reduce injury and bleeding. Make sure to complete follicular fluid aspiration within 25 to 30 minutes.

Pull out the needle after finishing in one ovary, wash the needle with the handling medium, and puncture the other side using the same method. Working in a 37 degrees Celsius homothermal flat, prepare the handling media, Petri dish, and cell strainer. Rinse the culture tube and strainer with pre-warmed pH stable handling media.

Filter the aspirated follicle fluid with a 70 micrometer nylon cell strainer, repeatedly rinsing the culture tube and strainer with pre-warmed pH stable handling medium. Ensure that all immature COCs are completely transferred to the culture dish. Transfer the blood into clean handling media.

Then, transfer the cell strainer to a new dish and wash it. Aspirate and transfer the handling media with the COCs, granulosa cells and tissues to a new dish. Examine the COCs under the stereoscope with 40 times magnification.

Quickly transfer the immatures into a pre-warmed IVM oocyte medium. Next, examine the COCs in the blood clot and in the cell strainer. Transfer the COCs and handling media into pre-warmed IVM oocyte medium.

Culture the immature COCs for 28 to 32 hours at 37 degrees Celsius in humidified air containing 5%carbon dioxide and 5%oxygen. By December 2019, OP-IVM had been used for fertility preservation of 274 patients. One example was a 28 year old patient who was diagnosed with primary infertility, left adnexal cyst, and PCOS.

She received laparoscopic cystectomy and OP-IVM in September 2016 and 27 immature COCs were obtained. After 28 hours in culture, seven oocytes in the MII stage were selected and fertilized by ICSI. After five days, two blastocysts were frozen.

One was thawed in February 2017 and transferred into the uterus. The patient delivered a healthy girl in November. OP-IVM was first applied to the oocyte retrieval of infertile women with PCOS who are undergoing ovarian drilling operation, and now its applications can be expanded to the subfertile women who need to receive benign gynecological operation, even cancer women for fertility preservation.

It indicates that the application range of IVM can be expanded by combining it with other traditional gynecological operations for female fertility preservation.