Live birth from a blastocyst derived from a conjoined oocyte in a frozen embryo transfer cycle: a case report and a literature review.

The significance of conjoined oocytes in the clinical in vitro fertilization (IVF) laboratory setting has been questionable due to the extremely limited data available. This issue is discussed by presenting one case for conjoined oocyte observed in the program of the assisted reproduction and by including a review of corresponding literature. This report describes a successful clinical pregnancy with subsequent live birth from a conjoined oocyte. To our knowledge, there are only three reported cases of successful live birth from conjoined oocytes, but this is the first case of live birth from a blastocyst derived from a conjoined oocyte fertilized using intracytoplasmic sperm injection (ICSI) in a frozen embryo transfer cycle. Moreover, this study reports the first time that live birth of a conjoined oocyte is achieved without removing the degenerated immature oocyte prior to transfer. It demonstrates that the degenerated immature oocyte has no adverse effect on subsequent embryo development and pregnancy outcome. In addition, we reviewed the literature to evaluate the origin, incidence, safety, and significance of conjoined oocytes in reproductive health. We further confirm previous reports that demonstrate that a mature oocyte from conjoined-oocyte complexes can be fertilized by standard IVF or ICSI and lead to the development of a blastocyst, subsequent pregnancy, and live birth.

Fertilization and development of oocytes with separated and conjoined zona pellucida recovered from polyovular follicles: description of two cases and a literature review.

Recovery of more than one oocyte from a single follicle during laparoscopic egg collection has been reported sporadically and accepted as confirmation of the presence of polyovular or binovular follicles in the human ovary at reproductive age. Most of these reports include conjoined oocytes that share common or fused zona pellucida, and are generally accepted as evidence for true polyovularity due to its certain characteristics. In this study, we report one case of a conjoined oocyte and another case of the recovery of two separate oocytes in a cumulus cell complex and details of their early embryonic development. To our knowledge, this report of the recovery of two separate oocytes without zonal contact is the first in the literature. We reviewed the relevant literature to evaluate information regarding the origin, incidence and significance of polyovularity in reproductive health.

Live birth resulting from a conjoined oocyte confirmed as euploid using array CGH: a case report.

The significance of conjoined oocytes in the clinical IVF laboratory setting has been of question due to the extremely limited data available. The most reliable criterion for true binovularity is the inclusion of two oocytes within a common zona pellucida or their fusion in the zonal region. This is a relatively rare event and owing to the limited number of embryo transfers performed and information on their outcomes, it is highly probable that these oocytes would be discarded without attempts at fertilization and subsequent embryo culture. To our knowledge, this is the first reported pregnancy resulting from a conjoined oocyte. Our experience involved a blastocyst transfer of a genetically screened embryo, performed after removal of the germinal vesicle from the conjoined oocyte/embryo on day 3. A clinical pregnancy with a gestational sac and fetal heartbeat was achieved and a healthy baby girl was delivered via Caesarean section at 37 weeks' gestation.