In vitro maturation of baboon oocytes retrieved at the time of cesarean section

Developmental competence of in vitro-matured human oocytes obtained from pregnant and non-pregnant women

Objective

The aim of this study was to compare the rate of maturation, fertilization, and embryo development of in vitro-matured human oocytes derived from pregnant and non-pregnant women.

Methods

Immature oocytes were obtained by needle aspiration from 49 pregnant women (group 1) who underwent a cesarean section at term and 77 non-pregnant women (group 2) who underwent a gynecological operation during the same period (8 months). Healthy immature oocytes (530 in group 1 and 539 in group 2) were cultured and assessed for maturation 36 hours later. Mature oocytes were inseminated by intracytoplasmic sperm injection and cultured up to 144 hours.

Results

The percentage of degenerated oocytes was significantly higher (12.1% vs. 6.3%; p<0.001) in group 1 than in group 2. There was no significant difference in the maturation rate (66.8% vs. 68.1%; p=0.698), fertilization rate (66.7% vs. 67.6%; p=0.857), or the rate of formation of good-quality blastocysts (46.2% vs. 47.2%; p=0.898) in oocytes obtained from pregnant and non-pregnant women.

Conclusion

The developmental competence of immature oocytes did not differ between pregnant and non-pregnant women.

Aspiration of immature oocytes during cesarean section for fertility preservation

BACKGROUND

In vitro maturation (IVM) of immature oocytes is an important technology for selected clinical indications. We previously described a pregnant woman with a history of renal transplantation who underwent oocyte aspiration during cesarean section (CS) for fertility preservation and future surrogacy.

CASE

A 27-year-old pregnant woman was diagnosed with neck rhabdomyosarcoma at 37 weeks' gestation. CS was performed with direct aspiration of small follicles from one ovary and oophorectomy of the other. Twenty-one identified oocyte-cumulus complexes were cultured, and 12 mature oocytes and 14 ovarian cortex strips were cryopreserved.

CONCLUSION

Aspirating competent oocytes during CS may serve as an additional means of fertility preservation in pregnant women. The procedure may also be offered to patients with an IVF pregnancy who are scheduled for elective CS.

Developmental competence of human embryos derived from in vitro maturation of immature oocytes retrieved during cesarean section

AIM

To investigate the developmental competence of human embryos that originated from in vitro matured oocytes retrieved during cesarean section.

METHODS

Immature oocytes were collected from 95 pregnant women, who underwent cesarean section at Buddhachinaraj Hospital Medical School and consented to participate in the study. Retrieved oocytes were cultured in blastocyst medium supplemented with 75 IU/L of human menopausal gonadotropin. Oocyte maturation was assessed at 30 and 48 h after culture. In vitro matured oocytes were inseminated by intracytoplasmic sperm injection and cultured up to 144 h. The fertilization, cleavage and blastocyst formation rates were observed.

RESULTS

Maturation rate of oocytes after 30 h of culture was 67.9% compared with 13.1% at 48 h (P < 0.0001). Insemination of oocytes in both groups resulted in similar fertilization, cleavage and blastocyst formation rates.

CONCLUSION

A large proportion of oocytes retrieved at the time of cesarean section exhibited the capacity to undergo maturation in vitro. They can be fertilized and developed into good-quality blastocyst stage.

In vitro oocyte maturation and preantral follicle culture from the luteal-phase baboon ovary produce mature oocytes

Female cancer patients who seek fertility preservation but cannot undergo ovarian stimulation and embryo preservation may consider 1) retrieval of immature oocytes followed by in vitro maturation (IVM) or 2) ovarian tissue cryopreservation followed by transplantation or in vitro follicle culture. Conventional IVM is carried out during the follicular phase of menstrual cycle. There is limited evidence demonstrating that immature oocyte retrieved during the luteal phase can mature in vitro and be fertilized to produce viable embryos. While in vitro follicle culture is successful in rodents, its application in nonhuman primates has made limited progress. The objective of this study was to investigate the competence of immature luteal-phase oocytes from baboon and to determine the effect of follicle-stimulating hormone (FSH) on baboon preantral follicle culture and oocyte maturation in vitro. Oocytes from small antral follicle cumulus-oocyte complexes (COCs) with multiple cumulus layers (42%) were more likely to resume meiosis and progress to metaphase II (MII) than oocytes with a single layer of cumulus cells or less (23% vs. 3%, respectively). Twenty-four percent of mature oocytes were successfully fertilized by intracytoplasmic sperm injection, and 25% of these developed to morula-stage embryos. Preantral follicles were encapsulated in fibrin-alginate-matrigel matrices and cultured to small antral stage in an FSH-independent manner. FSH negatively impacted follicle health by disrupting the integrity of oocyte and cumulus cells contact. Follicles grown in the absence of FSH produced MII oocytes with normal spindle structure. In conclusion, baboon luteal-phase COCs and oocytes from cultured preantral follicles can be matured in vitro. Oocyte meiotic competence correlated positively with the number of cumulus cell layers. This study clarifies the parameters of the follicle culture system in nonhuman primates and provides foundational data for future clinical development as a fertility preservation option for women with cancer.

Aspiration of immature oocytes during cesarean section for fertility preservation and future surrogacy

A 38-year-old pregnant patient with a history of renal transplantation sought embryo freezing for fertility preservation and future surrogacy. A cesarean section was performed with direct aspiration of small ovarian follicles. Thirteen identified oocyte-cumulus complexes were cultured. Intracytoplasmatic sperm injection was performed on all mature oocytes and the resulting 4 zygotes were cryopreserved.