Luteal phase start of low-dose FSH priming of follicles results in an efficient recovery, maturation and fertilization of immature human oocytes

In-vitro maturation of immature oocytes for infertile women with PCOS

Immature oocyte retrieval followed by in-vitro maturation (IVM) is a promising potential treatment option, especially for women who are infertile through polycystic ovarian syndrome (PCOS). Although the pregnancy and implantation rates of IVM treatment are not as high as conventional IVF treatment, IVM treatment has many advantages for infertile women with PCOS, because this group of patients is extremely sensitive to stimulation with exogenous gonadotrophins and is at increased risk of developing ovarian hyperstimulation syndrome (OHSS). Different protocols have been used before immature oocyte retrieval, indicating that there are beneficial effects with FSH or LH priming on oocyte maturation. To date, the clinical pregnancy and implantation rates obtained from IVM treatment in infertile women with PCOS are approximately 30-35% and 10-15% respectively. Therefore, as an option, IVM treatment can be offered to women with PCOS instead of conventional IVF treatment with ovarian stimulation.

Maturation in vitro des ovocytes : bilan et perspectives dans l’espèce humaine

Mature oocytes are rare and highly specialized cells. In vitro maturation of human oocytes is an emerging assisted reproductive technology allowing to produce more mature oocytes without ovarian stimulation. Whereas in vitro maturation is technically more demanding than conventional in vitro fertilization for the laboratory, it carries many potential advantages, for example, in terms of lower treatment heaviness and removal of risk of severe ovarian hyperstimulation syndrome for the patients. Although the technology is still experimental, oocytes in vitro maturation has been successfully used and pregnancies and live births have been reported. Despite these successes, the overall efficiency of in vitro maturation remains low and this procedure must still be improved. The different steps of in vitro maturation process are shown and discussed as well as results in terms of pregnancy and live birth rates.

Time interval between FSH priming and aspiration of immature human oocytes for in-vitro maturation: a prospective randomized study

This prospective randomized controlled study was performed to examine the influence of coasting for 2 days versus 3 days following a fixed daily dose of FSH for 3 days. The outcome was 2-fold. In the first experiment (n = 50 cycles), the incidence of apoptosis in granulosa cells was compared. In the second experiment (n = 28 cycles), the rates of maturation, fertilization, cleavage, pregnancy and implantation were compared. In addition, clinical pregnancy rate per aspiration was registered. Granulosa cells were collected from follicular aspirates and pooled for each patient. The APOPTAG Detection Kit was used for staining of the granulosa cells and detection of apoptosis. Oocytes were matured in vitro for 28-30 h before intracytoplasmic sperm injection. The incidence of apoptosis in granulosa cells did not differ between granulosa cells obtained after 2 days coasting (n = 25 cycles) compared with granulosa cells obtained after 3 days coasting (n = 25 cycles) (26.2 versus 26.2%). When oocytes obtained after coasting for 2 days (n = 12 cycles) were compared with oocytes obtained after coasting for 3 days (n = 16 cycles), no significant difference was found between rates of maturation (63 versus 65%), fertilization (60 versus 68%), cleavage (86 versus 92%) or implantation [5/12; 42 versus 1/12 (8%)]. A higher clinical pregnancy rate per aspiration [5/16 (31%) versus 1/12 (8%)] was obtained after coasting for 3 days compared with coasting for 2 days. The difference was not significant. This randomized study showed no difference in apoptosis of granulosa cells and no difference in developmental competence of oocytes obtained after coasting for 3 days compared with 2 days coasting.

FSH priming improves oocyte maturation, but priming with FSH or hCG has no effect on subsequent embryonic development in an in vitro maturation program

AIM

To determine whether maturation and subsequent blastocyst development of in vitro matured oocytes can be improved by in vivo follicle stimulating hormone (FSH) or human chorionic gonadotrophin (hCG) priming, using a mouse model.

EXPERIMENTAL DESIGN

Five groups of oocytes were used: in vivo control, in vitro matured (IVM) control, IVM after 24 h in vivo priming with FSH, IVM after 48 h in vivo priming with FSH and IVM after 16 h in vivo priming with hCG. In vitro fertilization (IVF) was performed on all groups. Oocyte maturation, fertilization, blastocyst development rates and blastocyst cell numbers were assessed for all groups.

RESULTS

Significant improvement in oocyte maturation was observed in the two FSH priming groups compared with the IVM control group (P<0.005 and P<0.001, respectively). There were no significant differences in fertilization between all five groups. Blastocyst development was significantly higher in the in vivo control compared to the IVM groups (P<0.001). No significant differences were observed in blastocyst cell numbers among all five groups.

CONCLUSIONS

While FSH priming improves the maturation rate of IVM oocytes, FSH or hCG priming does not improve development to the blastocyst stage.

Maternal serum supplementation in culture medium benefits maturation of immature human oocytes

This study compared the rates of maturation, fertilization, cleavage and pregnancy among oocytes matured in medium containing either human serum albumin (HSA) or maternal serum. Immature oocytes were obtained from 51 consecutive regularly cycling women <38 years of age. Immature oocytes were aspirated transvaginally on cycle day 8-9 after priming with FSH (Gonal-F 150 IU/day for 3 days, initiated on day 3). Oocytes were matured in Dyrkningsmedie til IVM supplemented with recombinant FSH (rFSH) 0.075 IU/ml and HCG 0.5 IU/ml for 28-30 h. In group I (n = 63 oocytes obtained from the first 23 cycles) the culture medium was supplemented with 2% (w/v) HSA. In group II (n = 74 oocytes obtained from the following 28 cycles) the medium was supplemented with 10% (v/v) heat-inactivated maternal serum. Intracytoplasmic sperm injection (ICSI) was performed on all methaphase II oocytes. Significantly increased rates of maturation 47/74 (63%) vs. 26/63 (41%) (P < 0.05), pregnancy 6/28 (21%) vs. 0/23 (0%) (P < 0.05) and implantation 6/20 (30%) vs. 0/15 (0%) (P < 0.05) were obtained from oocytes matured in culture medium with maternal serum supplementation compared with oocytes matured in medium supplemented with HSA. These results indicate that factors other than albumin in maternal serum play an important role in maturation and subsequent developmental capacity of human oocytes.

In vitro maturation and fertilization of oocytes from unstimulated normal ovaries, polycystic ovaries, and women with polycystic ovary syndrome

OBJECTIVE

To investigate differences in immature oocyte maturation, fertilization, and pregnancy rates among women with unstimulated normal ovaries, polycystic ovaries (PCOs), or PCOS.

DESIGN

Prospective observational study.

SETTING

University fertility clinic.

PATIENT(S)

One hundred forty-four women undergoing 180 in vitro oocyte maturation treatment cycles.

INTERVENTION(S)

Transvaginal immature oocyte recovery from unstimulated ovaries 36 hours after hCG priming. In vitro oocyte maturation and fertilization. Fresh embryo transfer.

MAIN OUTCOME MEASURE(S)

Immature oocytes collected, metaphase II oocytes, and embryos produced. Implantation and pregnancy rates.

RESULT(S)

The overall oocyte maturation and fertilization rates attained were 80.3% (1,222 of 1,522) and 76.5% (935 of 1,222), respectively. Significantly fewer immature oocytes were retrieved from normal ovaries (5.1 +/- 3.7) compared with the PCO (10.0 +/- 5.1) or PCOS (11.3 +/- 9.0) groups. Fertilization and cleavage rates were comparable among the three groups. The implantation, pregnancy, and live birth rates per transfer for normal ovaries were 1.5%, 4.0%, and 2.0%, respectively; for PCOs 8.9%, 23.1%, 17.3%, respectively; and for women with PCOS 9.6%, 29.9%, and 14.9%, respectively.

CONCLUSION(S)

Immature oocytes retrieved from normal ovaries, PCOs, or women with PCOS, when using hCG priming before oocyte retrieval, have a similarly high maturation, fertilization, and cleavage potential. In vitro maturation is a useful treatment option, particularly for women with PCOs.

Pregnancy/implantation rates as related to age following transfer of frozen embryos produced by ICSI

A study has suggested that one drawback of ICSI is that if these embryos are cryopreserved they have lower implantation rates after thawing and transfer as compared to other frozen embryos derived from conventional oocyte insemination. Other studies have not shown such adverse effects on pregnancy rates following frozen embryo transfer (ET) of embryos formed by ICSI. The study presented here evaluated the largest number of frozen ET cycles of embryos following ICSI, which were compared to couples having frozen ET with embryos formed by conventional insemination. In women age 39 and younger, the clinical, viable, pregnancy rates and implantation rates were very similar. Similar rates were reached for the older group. These data convincingly demonstrate that fertilization by ICSI does not adversely effect the implanting capacity of frozen-thawed embryos.