Combination of IVF and IVM in naturally cycling women

Abstract

This study investigated the combination of an unstimulated IVF cycle with in-vitro maturation (IVM) of additional immature cumulus–oocyte–complexes (COC) from the same cycle collected at the same time as the spontaneous preovulatory follicle. This could potentially improve rates of embryo transfer and pregnancy/live births compared with conventional unstimulated IVF treatment and at the same time eliminate the risk of ovarian hyperstimulation syndrome. This prospective trial included 77 women with regular menstrual cycles. Age at inclusion was between 20 and 37 years. Results showed a retrieval rate of mature oocytes of 50/80 (62.5%) per cycle started and immature COC were collected in 74/80 (92.5%) cycles. The embryo transfer rate was 28/80 (35.0%) with mature oocytes and increased in total to 43/80 (53.8%) with IVM oocytes. Corresponding birth rates per transfer were 3/28 (10.7%) and 4/43 (9.3%). Birth rates per aspiration were 3/76 (3.9%) and 4/76 (5.3%). It is concluded that the protocol described here shows proof of concept, but the impact of the IVM procedure only reached a significant level regarding embryo transfer, not with live births. The reason for this is yet unclear, but asynchrony between endometrial factors and IVM oocytes together with unknown competence of IVM embryos is suspected.

Nondominant small follicles are a promising source of mature oocytes in modified natural cycle in vitro fertilization and embryo transfer

“…These oocytes are matured in vitro before fertilization and eventually used for ET (2). This combination (natural cycle IVM/IVF) enhances the pregnancy rate for natural cycle IVF by 36%, compared with that for natural cycle IVF using only dominant-follicle oocytes (2,3). The rationale for IVM/IVF is the retrieval of immature oocytes from nonselected small follicles before the oocytes have lost their developmental competency (4,5).…”

Follicular fluid and supernatant from cultured cumulus-granulosa cells improve in vitro maturation in patients with polycystic ovarian syndrome

“…Previous studies have shown that, upon IVM, nearly 50% of immature oocytes reach maturation after 24-28 hours (28). Heterogeneous embryological outcomes have been reported concerning maturation (33%-82%), fertilization (19%-80%), and cleavage rate (7%-96%) after IVM (29)(30)(31)(32)(33)(34)(35). In the case of PCOS, IVM is a mild adjunct approach to IVF to achieve in vitro oocyte maturation and enhance oocyte competency for embryonic development until implantation.…”

Modified natural cycle in in vitro fertilization

“…The live birth rate was 8.6% per oocyte from nondominant follicles and 19.3% per oocyte from dominant follicles, showing that secondary follicles can lead to successful pregnancies (19). For immature oocytes, in vitro maturation (IVM) is well described in the literature and has led to successful pregnancies (20,21). Whereas most experience with IVM comes from polycystic ovary syndrome patients, IVM can be applied to mnIVF cycles to substantially increase the oocyte yield and overall chances of success (18)(19)(20)(21)(22).…”

“…For immature oocytes, in vitro maturation (IVM) is well described in the literature and has led to successful pregnancies (20,21). Whereas most experience with IVM comes from polycystic ovary syndrome patients, IVM can be applied to mnIVF cycles to substantially increase the oocyte yield and overall chances of success (18)(19)(20)(21)(22). Although initial data showed a potential association of IVM with chromosomal abnormalities (23), recent studies report no major differences in abnormalities and complication rates between IVF and IVM pregnancies (24).…”