Pregnancy after transfer of embryos which were generated from in-vitro matured oocytes

Abstract

In-vitro maturation of human oocytes is an important technique in assisted reproduction due to its potential for reducing the use of fertility drugs. We offered this technique as an alternative to cancelling the cycle to a patient who was at risk of ovarian hyperstimulation syndrome (OHSS) after treatment with gonadotrophin-releasing hormone analogue (GnRHa) and human menopausal gonadotrophin (HMG). The patient had 40 visible antral follicles with a maximum diameter of 13 mm and an oestradiol concentration of 14,000 pmol/l on cycle day 12. Immature oocytes were aspirated transvaginally under ultrasound guidance. Ten cumulus-enclosed oocytes were harvested and nine of them completed nuclear maturation to metaphase II after 48 h in culture. By 18 h after an intracytoplasmic sperm injection (ICSI) procedure, seven of these metaphase II stage oocytes displayed two distinct pronuclei and two polar bodies. All fertilized oocytes but one underwent cleaveage; four of these were transferred 2 days later. Endometrial priming was initiated with 8 mg oestradiol valerate daily from the day of oocyte retrieval and 50 mg progesterone was injected i.m. daily starting 2 days after that. A single intrauterine sac was seen containing one fetus with positive fetal heart beat on ultrasound at 7 weeks of gestation. Unfortunately, the pregnancy ended at 24 weeks shortly after premature rupture of membranes; a live healthy-looking girl was delivered who died 18 days later.

Gamete and Embryo Manipulation

“…83 Additional studies support these observations, showing that in vitro matured oocytes can be normally fertilized, however embryos derived from these oocytes rarely result in pregnancies. 84,85 These results suggest that rescue of MI oocytes of patients with few MII oocytes may increase the number of embryos for transfer; however, the chance to improve pregnancy rates by this procedure is minimal. Germinal vesicle-stage oocytes require overnight (30 hours) incubation in order to reach the MII stage.…”

“…Few pregnancies have been reported from oocytes that were retrieved at the GV stage although standard IVF treatment with controlled ovarian hyperstimulation was performed. 84,86 Because of the poor results, GV oocytes are usually discarded. Denuded and rinsed oocytes are incubated until the time of microinjection.…”

Oocyte Maturation in Humans: the Potential Relevance to Reproductive Medicine

“…This group of patients are most suitable because they have the highest risk of hyperstimulation from gonadotropins and they have a large crop of follicles for oocyte harvest. Whereas there is evidence that GV oocytes removed from women with PCOS have a lower maturation potential than oocytes harvested from women with regular menstrual cycles, acceptable pregnancy rates have been achieved in this particular group of patients [22,40,41].…”

“…IVM has been used successfully to treat patients in whom human chorionic gonadotropin (hCG) has been withheld both unintentionally because of patient forgetfulness and intentionally in individuals at risk of severe ovarian hyperstimulation syndrome [39,40], but the prime candidates for IVF are women with PCOS [9,22,41]. This group of patients are most suitable because they have the highest risk of hyperstimulation from gonadotropins and they have a large crop of follicles for oocyte harvest.…”

In vitro maturation may prevent the cancellation of in vitro fertilization cycles in poor responder patients: A case report

“…Under these circumstances, in vitro maturation (IVM), fertilization and embryo transfer may provide an alternative to cancellation of these cycles. Moreover, the development of the in vitro maturation technique could provide a new strategy for assisted reproduction, enabling cost reduction and minimizing concerns about a possible association between the use of ovulation-inducing drugs and their side effects (1). The IVM technique was first demonstrated by Pincus and Enzmann (1935) and later by Edwards (1969).…”