Development of embryos from natural cycle in-vitro fertilization: impact of medium type and female infertility factors

Relationship between even early cleavage and day 2 embryo score and assessment of their predictive value for pregnancy

The aim of this study was, firstly, to define the different patterns of early cleavage (EC) observed at 26 h after either IVF or intracytoplasmic sperm injection (ICSI) and, secondly, to assess the predictive value of one of these patterns, even EC (EEC), on pregnancy rate in combination with day 2 embryo score. In the first part of the study, the relationship between three different EC patterns (EEC, uneven EC and EC with fragmentation of the day 2 embryo) and embryo morphology was determined. EEC was shown to be strongly associated with good embryo morphology. In the second part of the study, it was shown that EEC used in combination with embryo score improved selection of embryos for transfer. The presence of EEC significantly (P < 0.001) enhanced mean implantation rate in all transfer categories involving identically scored embryos, in both compulsory single embryo transfers and elective single embryo transfers. Multivariate analysis demonstrated that EEC and embryo score had strong complementary predictive value for pregnancy. Based on these findings, it was concluded that even though they are associated, EEC and embryo score could be combined to increase pregnancy rate, especially in elective single embryo transfer programmes.

Comment améliorer nos résultats en AMP ? La France est-elle en retard ? Stratégie de transfert de l'embryon unique : la place du choix de l'embryon et de la congélation embryonnaire

Multiple embryo transfer is associated with a high frequency of twin pregnancies with costly complications involving both mother and child. As a result high priority is currently being given to the development of single embryo transfer (SET) programs. France seems to be lagging behind Northern European countries in the development of SET and widespread use of SET will depend on convincing physicians that this policy will not have a negative impact on success rate, as has been the case for many protocols described in the literature as well as in our own experience. Our SET program includes patients less than 36 years of age undergoing their first FIV-ICSI. If two embryos showing satisfactory morphology are obtained, one is selected transferred and the other is systematically frozen. Selection for transfer is based on two criteria, i.e. observation of even early cleavage 26 hours after FIV-ICSI and evaluation of embryo morphology score on day 2. Embryo morphology score is based on the presence of four blastomeres and absence of blastomere irregularities and anucleated fragmentation. Last, a prerequisite for SET is an effective freezing program. A pregnancy rate of 13% per thawing was sufficient enough to obtain a cumulative pregnancy rate after SET (N = 205) and subsequent frozen embryo transfer (FET) similar to the cumulative pregnancy rate obtained after double embryo transfer (N = 394) and subsequent FET (46.3 vs 46.7%, NS). Twin delivery rate were respectively 2,6% after SET and 26,6% after double embryo transfer (P < 0.01).

Minimal stimulation using recombinant follicle-stimulating hormone and a gonadotropin-releasing hormone antagonist in women of advanced age

OBJECTIVE

To determine whether minimal stimulation with short-term application of low-dose recombinant follicle-stimulating hormone (FSH) together with a gonadotropin-releasing hormone (GnRH) antagonist represents a cost-effective treatment regimen for patients with elevated FSH levels, aged 40 and above.

DESIGN

Retrospective cohort study.

SETTING

Academically affiliated private in vitro fertilization (IVF) program.

PATIENT(S)

Eighty-five IVF cycles using minimal ovarian stimulation and 85 cycles with a standard long-stimulation protocol, conducted between January 2000 and January 2002, in women aged 40 and above who had slightly increased FSH levels.

INTERVENTION(S)

Patients on the long protocol underwent standard cycle monitoring and stimulation. In contrast, women with minimal stimulation had transvaginal sonography initiated on day 8 of the menstrual cycle and at a follicle size of 13 mm. We administered 0.25 mg of GnRH antagonist and 75 IU recombinant FSH daily until ovulation induction.

MAIN OUTCOME MEASURE(S)

Numbers of oocytes, and rates of cancellation and pregnancy.

RESULT(S)

Minimal stimulation cycles resulted in a clinical pregnancy rate of 8.2% per started cycle and 10% per embryo transfer (ET), whereas the control group yielded a clinical pregnancy rate of 10.6% per started cycle and of 10.7% per ET (not statistically significant).

CONCLUSION(S)

In women aged 40 and above with abnormal FSH levels, minimal stimulation protocol achieves similar pregnancy rates to a standard protocol, and thus represents a cost-effective alternative.

Natural-cycle in vitro fertilization in women aged over 44 years

Women who are 44 years of age or more are usually denied infertility treatment because of their low response to ovarian stimulation and the extremely low pregnancy rate that can be achieved. The object of this study was to assess the place of natural-cycle in vitro fertilization (IVF) in this population. From January 1996 to September 1997, all consecutive women aged 44-47 years who approached our unit seeking infertility treatment with their own oocytes were enrolled in the study. After a counselling session in which the advantage of egg donation was discussed, women who still wished to try to conceive by utilizing their own oocytes were treated according to the following protocol. Ultrasound and hormonal surveillance was carried out starting 5 days prior to the presumed ovulation day, based on previous menstrual history. Ovum pick-up was timed either by detection of the luteinizing hormone surge or by human chorionic gonadotropin administration. In total, 48 treatment cycles were conducted in 20 women. Oocyte retrieval was successful in 22 cycles. Fertilization and cleavage rates of 48% and 100%, respectively, were detected. Nine of the 12 embryos transferred were defined as grade A. One chemical and one ongoing pregnancy were achieved. We conclude that, despite the fact that high-quality embryos can be obtained in this population, the likelihood of pregnancy is low.

Hydrosalpinx and ART: hydrosalpinx--functional surgery or salpingectomy?

The debate on the effect of the hydrosalpinx on medically-assisted reproduction has demonstrated the importance of understanding the complex pathophysiology of the hydrosalpinx in outlining the principles of its clinical management, whether it is by functional surgery or IVF, preceded or not by salpingectomy. New endoscopic techniques are available to accurately assess, both in the operating room and the office, the quality of the tubal mucosa. The direct endoscopic evaluation of the tubal mucosa in hydrosalpinges is at present the most reliable technique to select between functional surgery and preventive salpingectomy. In future, prospective randomized studies on salpingectomy will benefit greatly from accurate clinicopathological data.

The preovulatory serum estradiol pattern in natural IVF/ICSI cycles

PURPOSE

The aim of the study was to find whether inferences to the possible success of natural IVF/ICSI cycles could be drawn from the estradiol (E2) pattern.

METHODS

Sixty-eight women who underwent oocyte recovery in 98 natural cycles were recruited for the study. Daily serum E2 was measured in the preovulatory phase (-3 to +2 day). The E2 pattern was compared among four groups: Group A, unsuccessful egg retrieval; Group B, no fertilization; Group C, no implantation; and Group D, implantation.

RESULTS

There was no difference in mean E2 levels between groups. Only the ratio of E2 on day +1/E2 on day 0 was significantly lower in conception cycles in comparison with nonconception cycles. In cycles with a decreased E2 level on day +1, only the implantation rate was significantly higher in comparison with cycles with an increasing E2 level.

CONCLUSIONS

From the E2 pattern it is possible to make inferences about the likelihood of implantation but not the fertilization or oocyte recovery success.

Developmental failure in preimplantation human conceptuses

The majority of human conceptuses fertilized normally in vitro fail to establish a pregnancy following their replacement in utero. However, since conceptuses are usually transferred after only one or two cell divisions, their developmental outcome is not known. It has been found that a significant number of human oocytes which can be fertilized carry chromosomal abnormalities, even in the absence of ovarian stimulation. After fertilization, preimplantation-stage conceptuses developing in vitro display a high incidence of cellular abnormalities. Similar disruptions of cellular organization have also been noted in conceptuses fertilized in vivo. Thus, developmental abnormalities and the demise of the conceptus prior to the stage of implantation may stem from the poor quality of the oocyte. The conditions encountered in vitro have also been proposed to cause or contribute to the early demise of human conceptuses.

Embryo viability associated with microassisted fertilization

Embryo morphology and cleavage rates represent useful, but not absolute, measures of embryo viability. Oocyte and embryo chromosomal abnormalities affect embryo viability and are reflected to some degree in the morphology of oocytes and embryos. Microassisted fertilization techniques have been successfully used to treat severe male-factor infertility. Zona drilling using acidified Tyrode's solution is detrimental to oocyte and embryo viability and should not be used. Partial zona dissection (PZD) produces viable embryos that have developmental competence no different from that of routine IVF embryos, but the oocytes should be shrunken in hypertonic sucrose prior to PZD to avoid distortion and mechanical damage. The size of the cut in the zona pellucida is also critical and should be kept to a minimum to avoid loss of blastomeres during transfer. It appears from data on embryo quality, pregnancy rates and implantation rates that SUZI embryos have viability comparable to that of routine IVF embryos. Astonishingly, the passage of an injection needle directly into the ooplasm during ICSI has no effect on fertilization or developmental competence, as demonstrated by the excellent clinical pregnancy rates.