New Application of Sequential in Vitro Muturation System for Infertility Patients With Polycystic Ovary Syndrome

New Application of Sequential in Vitro Muturation System for Infertility Patients With Polycystic Ovary Syndrome

New Application of Oocyte Sequential Culture and in Vitro Muturation System for Infertility Patients With Polycystic Ovary Syndrome: a Multi-center Prospective Randomized Clinical Trial

Hospital for Reproductive Medicine Affiliated to Shandong University, The First Affiliated Hospital with Nanjing Medical University, First Affiliated Hospital of Wenzhou Medical University, Shanghai 10th People's Hospital

Oocyte in vitro maturation (IVM) is an artificial reproductive technologies (ART) in which cumulus-oocyte complex (COC) are collected at the immature germinal vesicle (GV) stage from unstimulated or FSH-primed ovaries and matured in vitro before fertilization. IVM has been proposed as a more patient-friendly ART alternative to conventional IVF. Contrary to IVF, IVM is the only ART method with no cases of OHSS reported. Hence, patients with PCOS represent the major target population for IVM treatment. In clinical practice of standard IVM, COCs are aspirated from unstimulated or mildly stimulated ovaries and rapidly removed from the meiotic-inhibiting influence of the follicle and the follicular fluid. Regardless of in vitro gonadotrophin treatment, oocytes mature spontaneously in vitro, hence undergoing meiotic resumption in the absence of the usual elaborate cascade of endocrine and paracrine molecular signals that induce maturation in vivo. As such, the maturation of oocytes by standard IVM techniques is an artefact that compromises subsequent oocyte developmental competence. Numbers of studies have been proposed to improve the efficiency of IVM system. Synchronization of meiotic and cytoplasmic maturation in antral oocytes arrested at the immature GV-stage remains a major challenge and is of fundamental importance for successful fertilization. High intra-oocyte levels of cyclic adenosine monophosphate (cAMP), is crucial to maintain the nearly fully-grown oocytes under meiotic arrest and to induce oocyte maturation. Research in animal models has indicated that a non-physiological drop of cAMP levels in the oocyte results in asynchronous nuclear and cytoplasmic maturation. Investigators have reported the development of a novel in vitro simulated sequential oocyte maturation system. Critical to success of the approach is a pre-IVM phase that generates a rapid increase in COC cAMP levels. Secondly, the system utilizes an extended IVM phase containing sufficient FSH to drive meiotic induction in the presence of a type-3 PDE inhibitor. The high levels of cAMP in the oocyte and the induced nature of oocyte maturation mimics some of the key, newly characterized molecular signals that occur during oocyte maturation in vivo. Technical and conceptual elements were first developed using mouse, bovine and human COCs. Investigators propose a randomized clinical trial to compare a novel sequential culture system with the traditional standard oocyte IVM system for PCOS patients.

A multi-center, prospective, randomized clinical trial will be conducted, of comparing sequential oocyte IVM system with traditional oocyte IVM system for high OHSS risk PCOS patients (AMH>5.6ng/ml). The inclusion criteria will be infertile patients diagnosed by the Chinese PCOS criteria, aged below 35 years, and without other known factors interfere reproductive or metabolic functions. 300 PCOS patients will be included and randomized into either of two groups: group A will administrate sequential oocyte IVM system and group B will administrate traditional standard oocyte IVM system. The comparison will be made between groups, and both groups are conducted with the HMG administration and embryo vitrification freezing. The primary outcome of the study is live birth rate. The embryo development and pregnancy outcomes will be followed up and compared between groups.

From day 7~9 of the menstrual cycle, 225 IU HMG (Menotrophins for Injection) per day will be administrated for 3 days. COCs were removed from aspirated follicular fluid and transferred into HEPES-buffered collection medium. The immature oocytes will be cultured in sequential IVM medium 1 for 6 hours (37℃, 5% CO2), and removed into sequential IVM medium 2 for further cultivation. After 24 and 40 hours cultivation, the mature oocytes will be fertilized by intracytoplasmic sperm injection (ICSI). Two of the D3 embryos (if available) which graded as top-quality embryo will be vitrified and the rest of embryos will be cultivated extendedly. Thawed embryo transfer (TET) will give preference to D3 embryos and carried out with a hormone replacement cycle.

From day 7~9 of the menstrual cycle, 225 IU HMG (Menotrophins for Injection) per day will be administrated for 3 days. On the day of ovulation, COCs were aspirated and the immature oocytes will be cultured in traditional standard oocyte IVM system (Sage). 30 and 44 hours after cultivation, the maturity of oocytes will be assessed and the mature oocytes will be fertilized by intracytoplasmic sperm injection (ICSI). Two of the D3 embryos (if available) which graded as top-quality embryo will be vitrified and the rest of embryos will be cultivated extendedly. Thawed embryo transfer (TET) will give preference to D3 embryos and carried out with a hormone replacement cycle. If biochemical pregnancy is not achieved, thawed blastocysts transfer will be performed.

The immature oocytes will be cultured in sequential oocyte IVM medium 1 for 6 hours (37℃, 5% CO2). After flushed 3 times, COCs were removed into sequential oocyte IVM medium 2 for further cultivation.

Patients administrates oestrogen (Progynova) 3mg twice a day for 10 to 12 days. From the day when endometrium reach a thickness of 8 mm and above, luteal phase support will be given with 10 mg progesterone (Dydrogesterone Tablets,) triple per day and utrogestan (Laboratories Besins International, Paris, France) 0.2g triple per day, until 14 days after embryo transfer.

COCs were aspirated and the immature oocytes will be cultured in traditional standard oocyte IVM system (Sage). 30 and 44 hours after cultivation, the maturity of oocytes will be assessed.

The fetal heart beat in an intrauterine gestational sac under ultrasound will be defined as clinical pregnancy.

Good quality embryo rate at cleavage-stage (%): number of good quality embryos at cleavage-stage / number of 2PN embryos.

Available embryos will be defined as three days after oocyte retrieval with containing more than 4 cells and grade 1 to 2 or containing 4 cells with a grade of 1.

A serum β-hCG level above 5 IU/L, which is performed 12 days after embryos transfer, will be defined as biochemical pregnancy.

The implantation rate will be defined as the number of gestational sacs seen on the ultrasound divided by the total number of embryos transferred.

Miscarriage at first trimester will be defined by any positive pregnancy test that result in a loss of pregnancy before 12 weeks gestation.

Cumulative pregnancy rate will be defined as clinical pregnancies with intrauterine fetal heart beat detected divided by the number of retrieval cycles whose embryos are all transferred.

We will collect complications that occur in the neonate including admission to the neonatal intensive care unit (NICU), hospitalization, etc.

Inclusion Criteria: Women age ≤35 years; AMH level ≥5.6ng/ml; Women diagnosed as PCOS according to Chinese PCOS diagnosis criteria; Written informed consent. Exclusion Criteria: Women who diagnosed as uterus abnormality, adenomyosis, submucous myoma, intrauterine adhesion; Women who diagnosed as untreated hydrosalpinx; Women who had underwent unilateral ovariectomy; Women with medical condition that represent contraindication to assisted reproductive technology or pregnancy; Women or their partner with abnormal chromosome karyotype; Male partner with oligoasthenozoospermia or obstructive azoospermia; Male partner whose sperm is collected by surgery; Subjects are found breach the inclusion criteria, or in accordance with exclusion criteria during the test, excluded; Patients request withdrawal and exit the trial because adverse events occur during the trial.