Selection of patients for natural cycle in vitro fertilization combined with in vitro maturation of immature oocytes

Fertilization, embryo development, and clinical outcome of immature oocytes obtained from natural cycle in vitro fertilization

“…In a case series reported by Chian et al [7] three pregnancies were achieved after the combination of natural cycle IVF/M and transfer of resulting embryos. Lim et al [10] reported good pregnancy rates after performing natural cycle IVF/M. Based on these studies, Chian and Lim have suggested that developmental competence of immature oocytes is not detrimentally affected by the presence of any size of the DF during the follicular phase and the embryos produced from the immature oocytes could contribute to an increased chance of a pregnancy.…”

“…In this study, therefore, we collected data from patients who had the same protocol of natural cycle IVF/M as previously reported [8,10] and analyzed the embryological and clinical results of natural cycle IVF for women who had normal ovaries. We compared embryos produced from oocytes matured in vivo and in vitro and found that sibling immature oocytes could mature in vitro, fertilize and some of them could develop to good quality embryos similar to the animal model that was reported by Chian [16].…”

“…Transvaginal ultrasound scans were repeated on day 7-9 and repeated at 1-3-day intervals until the leading follicle reached over 12 mm in diameter and the endometrial thickness was≥6 mm. At this point 10,000 IU hCG was administered [9,10].…”

“…Recently, the concept of "natural cycle IVF combined with IVM (IVF/M)" has been proposed, which suggests that natural cycle IVF might be combined with immature oocyte retrieval and IVM [7][8][9][10][11]. In addition to the embryo produced by the mature oocyte from the DF, embryos produced by the IVM oocytes will also be available, therefore possibly increasing the chances of pregnancy in a natural cycle.…”

“…Administrating hCG when the DF reaches 14 mm diameter Capsule Although immature oocytes from natural cycle IVF can fertilize normally and can be used to increase the number of embryos available for transfer, the embryos derived from the immature oocytes in natural cycles IVF have a poorer reproductive potential. [8] or more recently 12-14 mm [9][10][11] to obtain mature oocytes and viable sibling immature oocytes has been recommended. However, evidence is lacking on whether the immature oocytes retrieved after the follicle gains dominance (> 12 mm) in a natural cycle actually contribute to the pregnancy rate.…”