IVM of human immature oocytes for infertility treatment and fertility preservation

Background

Thousands of healthy babies are born from in vitro maturation (IVM) procedures, but the rate of efficiency differs with the source of immature oocytes obtained. Recently, there are different IVM protocols proposed for infertility treatment and fertility preservation.

Methods

Based on the literature, the clinical application for IVM of immature oocytes was summarized.

Main findings Results

Immature oocytes may be retrieved from women after priming with or without the use of follicular stimulation hormone (FSH), human chorionic gonadotrophin (hCG) or a combination of both FSH and hCG. Successful pregnancy rates with IVM technology seem to be correlated with the number of immature oocytes obtained. With the source and culture course of immature oocytes, there are various IVM protocols. IVM of immature oocytes is profoundly affected by the culture conditions, but no breakthrough has been made by improving the IVM medium itself. Thus, the clinical application of IVM technology continues to evolve.

Conclusion

IVM technology is a useful technique for infertile women and fertility preservation. Mild stimulation IVF combined with IVM of immature oocytes is a viable alternative to the conventional stimulation IVF cycle treatment as it may prove to be an optimal first-line treatment approach.

Current perspectives on in vitro maturation and its effects on oocyte genetic and epigenetic profiles

In vitro maturation (IVM), the maturation in culture of immature oocytes, has been used in clinic for more than 20 years. Although IVM has the specific advantages of low cost and minor side effects over controlled ovarian stimulation, the prevalence of IVM is less than 1% of routine in vitro fertilization and embryo transfer techniques in many reproductive centers. In this review, we searched the MEDLINE database for all full texts and/or abstract articles published in English with content related to oocyte IVM mainly between 2000 and 2016. Many different aspects of the IVM method may influence oocyte potential, including priming, gonadotrophin, growth factors, and culture times. The culture conditions of IVM result in alterations in the oocyte or cumulus cell transcriptome that are not observed under in vivo culture conditions. Additionally, epigenetic modifications, such as DNA methylation or acetylation, are also different between in vitro and in vivo cultured oocytes. In sum, current IVM technique is still not popular and requires more systematic and intensive research to improve its effects and applications. This review will help point our problems, supply evidence or clues for future improving IVM technique, thus assist patients for fertility treatment or preservation as an additional option.

Development of in vitro maturation techniques for clinical applications

In vitro maturation (IVM) refers to maturation in culture of immature oocytes at different stages that may or may not have been exposed to short courses of gonadotropins. The source of immature oocytes is an important feature for subsequent embryonic development, pregnancy, and healthy live births. IVM is an effective treatment that has already achieved significant outcomes of acceptable pregnancy and implantation rates and has led to the births of several thousand healthy babies. As the development of IVM treatment continues, an attractive possibility for improving the already successful outcome is to combine a natural-cycle in vitro fertilization (IVF) treatment with immature-oocyte retrieval followed by IVM of those immature oocytes. If the treatment processes can be simplified for immature-oocyte retrieval, different types of infertile women may be able to take advantage of these treatments. Mild-stimulation IVF combined with IVM treatment may represent a viable alternative to the standard treatment. Although IVM treatment is still considered to be experimental, it is now time to reconsider the IVM technology and its development. Mild-stimulation IVF combined with IVM may prove to be not just alternatives to standard treatments, but potentially first-line treatment choices.

Strategies for improving outcome of assisted reproduction in women with polycystic ovary syndrome: systematic review and meta-analysis

OBJECTIVES

To identify, appraise and summarize the current evidence regarding the efficacy of strategies aimed at improving assisted reproductive techniques in women with polycystic ovary syndrome (PCOS).

METHODS

A comprehensive literature search of the standard medical databases was performed. The last electronic search was run in July 2015. The primary outcome measures were live birth/ongoing pregnancy and ovarian hyperstimulation syndrome (OHSS). The secondary outcome measures were clinical pregnancy and miscarriage.

RESULTS

We screened 1021 records and completely assessed 173, finally including 66 studies in the quantitative analysis. Many different interventions were assessed, however the overall quality of the studies was low. We observed moderate-quality evidence that there is no clinically relevant difference in live birth/ongoing pregnancy rates (relative risk (RR), 0.95 (95% CI, 0.84-1.08)), or clinical pregnancy (RR, 1.02 (95% CI, 0.91-1.15)) when comparing antagonist and agonist protocols for ovarian stimulation. Additionally, we found low-quality evidence that metformin improves live birth/ongoing pregnancy (RR, 1.28 (95% CI, 1.01-1.63)) and clinical pregnancy rates (RR, 1.26 (95% CI, 1.04-1.53)) when compared with placebo or no intervention. We further found low-quality evidence that there is no clinically relevant difference in live birth/ongoing pregnancy rates (RR, 1.03 (95% CI, 0.80-1.34)) and clinical pregnancy rates (RR, 0.99 (95% CI, 0.81-1.22)) when comparing human menopausal gonadotropin for inducing ovulation and artificial preparation with estradiol valerate for endometrial preparation for frozen embryo transfer (FET). Low-quality evidence suggests that mannitol compared with no intervention (RR, 0.54 (95% CI, 0.39-0.77)) and antagonist protocols compared with agonist protocols (RR, 0.63 (95% CI, 0.49-0.80)) reduce rates of OHSS.

CONCLUSION

There is low- to moderate-quality evidence suggesting that antagonist protocols are preferable to agonist ones, because they reduce the incidence of OHSS without interfering with clinical pregnancy and live birth for women with PCOS. Additionally there is low-quality evidence pointing to a benefit of metformin supplementation on clinical pregnancy and live birth; and that ovulation induction and administration of estradiol seem to be equally effective for endometrial preparation before FET for women with PCOS. For all other interventions, the evidence is of very low quality, not allowing any meaningful conclusions to be drawn. Estrategias para mejorar el resultado de la reproducción asistida en mujeres con síndrome de ovario poliquístico: revisión sistemática y metaanálisis RESUMEN OBJETIVOS: Identificar, evaluar y resumir la evidencia actual sobre la eficacia de las estrategias para mejorar las técnicas de reproducción asistida en mujeres con síndrome de ovario poliquístico (SOP). MÉTODOS: Se realizó una búsqueda exhaustiva de literatura en las bases de datos médicas estándar. La última búsqueda electrónica se realizó en julio de 2015. Las medidas de resultado primarias fueron los nacimientos vivos/embarazos en curso y el síndrome de hiperestimulación ovárica (SHO). Las medidas de resultado secundarias fueron el embarazo confirmado ecográficamente y el aborto.

RESULTADOS

Se cribaron 1021 registros, de los que se evaluaron por completo 173, para finalmente incluir 66 estudios en el análisis cuantitativo. Aunque se evaluaron muchas intervenciones diferentes, en general la calidad de los estudios fue baja. Se observó evidencia de calidad moderada de que no hay diferencias relevantes clínicamente en las tasas de nacimientos vivos/embarazos en curso (riesgo relativo (RR): 0,95 (IC 95%, 0,84-1,08)), o de embarazos confirmados ecográficamente (RR: 1,02 (IC 95%, 0,91-1,15)), cuando se comparan los protocolos de antagonistas y agonistas para la estimulación ovárica. Además, se encontró evidencia de baja calidad en que la metformina mejora las tasas de nacimientos vivos/embarazos en curso (RR: 1,28 (IC 95%, 1,01-1,63)) y de embarazos confirmados ecográficamente (RR: 1,26 (IC 95%, 1,04-1,53)) en comparación con un placebo o la no intervención. Se encontró también evidencia de baja calidad en que no hay diferencias relevantes clínicamente en las tasas de nacimientos vivos/embarazos en curso (RR: 1,03 (IC 95%, 0,80-1,34)) y las tasas de embarazos confirmados ecográficamente (RR: 0,99 (IC 95%, 0.81-1,22)) al comparar la gonadotropina menopáusica humana para la inducción de la ovulación y la preparación artificial con el valerato de estradiol para preparar el endometrio para la transferencia de embriones congelados (TEC). La baja calidad de la evidencia sugiere que el manitol, en comparación con la no intervención (RR: 0,54 (IC 95%, 0,39-0,77)), y los protocolos de antagonistas, en comparación con los protocolos de agonistas (RR: 0,63 (IC 95%, 0,49-0,80)), reducen las tasas de SHO. CONCLUSIÓN: Hay evidencia de calidad baja a moderada que sugiere que los protocolos de antagonistas son preferibles a los de agonistas, ya que reducen la tasa de SHO sin interferir con el embarazo confirmado ecográficamente y los nacimientos vivos en las mujeres con SOP. Además, existe evidencia de baja calidad que indica un beneficio del uso de metformina como aporte suplementario en embarazos confirmados ecográficamente y en nacimientos vivos; y que la inducción de la ovulación y la administración de estradiol parecen ser igualmente eficaces para la preparación del endometrio antes de la TEC en mujeres con SOP. Para el resto de procedimientos, la evidencia es de muy baja calidad, y por ello no permite extraer conclusiones importantes.

The correlation of cumulus mucification patterns with oocyte maturation rate in vitro in FSH + LH-primed IVM cycles: a prospective study

PURPOSE

This prospective study was conducted to compare the oocyte maturation rate in vitro among four types of cumulus cell (CC) morphology, in dual gonadotropin-primed in vitro maturation (IVM) oocyte cycles.

METHODS

Two-hundred and thirty cumulus-oocyte complexes (COCs) were retrieved from FSH + hCG-primed in vitro maturation cycles of 20 patients diagnosed with polycystic ovarian syndrome. The COCs that contained immature oocytes were classified into four groups according to their cumulus mucification patterns (dispersed, clumped, compacted or sparse) and their oocyte maturation rates were compared. Chi square test and Fisher's exact test were used as appropriate.

RESULTS

Oocytes enclosed by dispersed and clumped CCs exhibited higher maturation rates than those with compacted and sparse patterns (P < 0.001).

CONCLUSION

In dual gonadotropin-primed IVM cycles, oocyte maturation rates are highest in those showing dispersed and clumped CC patterns.

Advantages of Recombinant Follicle-Stimulating Hormone over Human Menopausal Gonadotropin in Intrauterine Insemination: A Randomized Clinical Trial in Polycystic Ovary Syndrome-Associated Infertility

BACKGROUND

Various gonadotropin preparations have been used for ovarian stimulation in intrauterine insemination (IUI). The purpose of the current study was to compare human menopausal gonadotropin (hMG) and recombinant follicle-stimulating hormone (rFSH) combined with clomiphene citrate (CC) in IUI cycles for polycystic ovary syndrome-associated infertility.

METHODS

In this prospective trial, couples prepared for IUI cycles were randomly allocated either to receive CC and rFSH (group A, n = 132) or CC and hMG (group B, n = 144) for ovarian stimulation. Outcomes including rates of clinical pregnancy, miscarriage, ovarian hyperstimulation syndrome, multiple pregnancy, cancellation and live birth were compared.

RESULTS

The duration of gonadotropin therapy was shorter and total doses of gonadotropins was lower in the rFSH group. The number of stimulated follicles reaching >17 mm diameter was comparable between groups, but the mean follicular diameter was significantly higher in the rFSH group. The endometrium was also significantly thicker at the time of human chorionic gonadotropin administration in the rFSH group. However, pregnancy outcomes, including the rates of clinical pregnancy, ongoing pregnancy, live birth, miscarriage, ovarian hyperstimulation syndrome and cancellation, were similar between groups.

CONCLUSION

IUI cycles in which rFSH is administered may result in shorter duration of treatment, a lower total gonadotropin dose and better follicular and endometrial characteristics on the day of human chorionic gonadotropin injection. © 2015 S. Karger AG, Basel.