NaturalIn VitroFertilization Cycles

Impact of embryo quality and endometrial thickness on implantation in natural cycle IVF

Purpose

The aim of this study is to assess the effect of the endometrial thickness and embryo quality on the implantation potential in natural cycle IVF (NC-IVF).

Methods

A retrospective single-center study was performed on 552 single embryo transfers after NC-IVF. The ‘quality' of the embryos was evaluated trough the number and regularity of blastomeres, degree of fragmentation, and nuclear content of cells. Endometrial thickness was measured in millimeters with transvaginal ultrasound on the day of hCG application.

Results

Our findings showed a statistically significant difference in successful implantation until a plateau of 10 mm is reached (p = 0.001). Only one pregnancy was achieved where endometrial thickness was less than 7 mm, and this resulted in an early miscarriage. The predictors of favorable implantation were fragmentation (≤ 10%, p < 0.05) and the number of blastomeres (preferably 8-cell, p < 0.01) on day 3. Embryo quality (R = 0.052) and endometrial thickness (R = 0.18) were closely related to pregnancy rate. The overall implantation rate per embryo transfer was 18.8%.

Conclusions

Embryo quality and endometrial thickness have a significant impact on implantation in NC-IVF. Highest implantation potential has an 8-cell embryo with ≤ 10% fragmentation in the third day following oocyte retrieval. Endometrial thickness of at least 7 mm seems to be the optimal edge of successful pregnancy.

Natural cycle IVF: evaluation of 463 cycles and summary of the current literature

PURPOSE

Natural cycle (NC) IVF/ICSI has proven to be an alternative to conventional IVF/ICSI cycles.

METHODS

Within our retrospective, observational study (n = 159) infertile couples underwent (n = 463) cycles of NC-IVF/ICSI from May 2007 until December 2011. Oocyte pick-up was performed within a pure natural cycle excluding any hormonal stimulation except of hCG for ovulation induction. Oocytes were fertilized by IVF/ICSI and embryo transfer took place 2 or 3 days later. In addition, the current literature was analysed concerning pregnancy rates in NC-IVF/ICSI cycles.

RESULTS

Oocyte pick-up was performed in n = 463 NC and was successful in n = 342 cases (IVF n = 135, ICSI n = 207). 203 oocytes were fertilized (IVF n = 87, ICSI n = 116, FR 59.4 %) and lead to 192 embryo transfers. Finally, 25 pregnancies were reached (PR 13.0 % per transfer) resulting in four biochemical pregnancies, 7 (33.3 %) miscarriages, one pregnancy of unknown outcome and 13 live births. Within the current literature (n = 27 studies), PR in NC-IVF/ICSI cycles varied between 10.2 and 50 %.

CONCLUSIONS

Within our study, pregnancy rates in pure NC-IVF/ICSI remained below 15 %. Although this may be linked to unfavourable preconditions like patients' age >40 years, low ovarian reserve or long duration of infertility, further improvement is necessary to increase pregnancy rates.

Mild ovarian stimulation for in vitro fertilization: one perspective from the USA

PURPOSE

To provide a perspective regarding mild ovarian stimulation, taking into account particular issues relevant in the United States

METHODS

Literature review and editorial commentary

RESULTS

Mild ovarian stimulation for IVF has some proven and some theoretical advantages over conventional stimulation, such as lower risk of ovarian hyperstimulation syndrome and lower cost per fresh IVF cycle. However, cumulative live birth rate, including transfers from fresh and frozen embryos, is likely to be lower with mild stimulation. The cost-effectiveness of mild stimulation IVF in the United States has not been established.

CONCLUSIONS

Mild ovarian stimulation is an appropriate option to consider for certain patient groups or based on patient preference. However, significant potential disadvantages limit its widespread acceptability for patients in the United States at this time.

Modified natural cycle for in vitro fertilization and embryo transfer in normal ovarian responders

Controlled ovarian hyperstimulation (COH) using a gonadotrophin-releasing hormone (GnRH) analogue plus gonadotrophins is used widely in in vitro fertilization (IVF), but there can be significant complications. Sixty women with a normal ovarian response participated in a comparison of COH (triptorelin [GnRH agonist] 0.1 mg/day SC from day 21 of the menstrual cycle [before the IVF cycle] and recombinant follicle-stimulating hormone (FSH) 150 - 300 IU/day from day 2 of the IVF cycle, when triptorelin was reduced to 0.05 mg/day) with a modified natural cycle (MNC) treatment (human menopausal gonado trophin [HMG] 150 IU/day IM if serum oestradiol was ≤ 50 pg/ml on day 2 or 3 of the menstrual cycle). The groups did not differ significantly in implantation rate (21.1% and 22.6%, respectively) and clinical pregnancy rate (30.0% and 30.0%, respectively). When comparing successful pregnancies, MNC patients had significantly lower values than COH patients for total amount of gonadotrophin (HMG and recombinant FSH) used, number of oocytes retrieved and medication cost. It is concluded that MNC seems to be a feasible treatment option, with low medication cost, relatively low risk of complications and, possibly, greater patient acceptability.

Morphological selection of gametes

Methods of selecting gametes before the intracytoplasmic sperm injection (ICSI) technique are of paramount importance, especially where for religious, ethical or legal reasons the production of supernumerary embryos has to be avoided. In these circumstances, in fact, the research has to be focused on the identification of early markers of embryo quality at the oocyte and sperm stage before fertilisation. Oocyte quality can be influenced by several factors such as controlled ovarian hyperstimulation protocols, pharmaceutical preparations and perifollicular vascularisation. Several intracytoplasmic and extracytoplasmic abnormalities have been described, but whether these abnormalities might be predictive of oocyte competence is controversial and the selection methods proposed are still poorly effective. Recently, we have observed that oocyte morphological abnormalities might be indicators of oocyte competence. An abnormal first polar body (but not fragmented), a large perivitelline space, increased cytoplasmic granularity, and the presence of a centrally located granular area seem to have a negative effect on the oocyte potential to fertilise, cleave, and/or develop into a viable embryo. Sperm morphology can be more accurately observed at high magnification using an inverted microscope equipped with Normarski optics (1000x magnification under mineral oil) and a digital system in order to reach a final magnification of approximately 6300x. Single sperm nuclear abnormalities based on strict selection criteria seems to have a clear negative association with ICSI outcome. The possibility of observing the spermatozoa in real time at higher magnification might also be a good opportunity to study the relationship between particular sperm defects and ICSI outcome. In addition to morphology, it has been suggested that spermatozoa selection might be performed on the basis of its biochemical ability to bind to solid hyaluronic acid. However, it must be underlined that prospective randomised studies are necessary to confirm the preliminary results regarding the efficacy of the described criteria proposed, to morphologically select gametes prior to in vitro insemination.

Gene expression profiling of human peri-implantation endometria between natural and stimulated cycles

OBJECTIVE

To investigate the effect of high serum E(2) levels in gonadotropin-stimulated cycles (hCG+7) on the gene expression patterns of human endometrium compared with natural cycles on the seventh day of LH surge (LH+7) and elucidate the underlying molecular changes that may be related to endometrial receptivity.

DESIGN

Observational study.

SETTING

University Hospital.

PATIENTS(S)

Infertile patients with normal menstrual cycles undergoing IVF treatment.

INTERVENTION(S)

Gonadotropin stimulation and endometrial biopsy.

MAIN OUTCOME MEASURE(S)

Gene expression by microarray and quantitative polymerase chain reaction (qPCR).

RESULT(S)

Endometrial samples from natural (n = 5) and stimulated (n = 8) cycles were collected. Patients in the stimulated cycles were classified as moderate (n = 4) or excessive (n = 4) responders if their serum E(2) levels on the day of administration of hCG were <or=20,000 pmol/L or >20,000 pmol/L, respectively. The RNA transcripts were profiled by Affymetrix HG-U133A microarray. Clustering and principal component analysis demonstrated a significant difference (>or=2-fold) in the expression patterns of 411 genes among the three groups. Putative estrogen response elements or progesterone response elements were identified in the promoter regions of 49 differentially expressed genes of diverse biologic functions. The qPCR confirmed the microarray result in 47 endometrial samples.

CONCLUSION(S)

High serum E(2) and/or progesterone modulate the gene expression profiles of human endometrium and may affect endometrial receptivity.

A prospective, randomised, controlled clinical study on the assessment of tolerability and of clinical efficacy of Merional (hMG-IBSA) administered subcutaneously versus Merional administered intramuscularly in women undergoing multifollicular ovarian stimulation in an ART programme (IVF)

BACKGROUND

Multifollicular ovarian stimulation (MOS) is widely used in IVF and the compliance to treatment is deeply influenced by the tolerability of the medication(s) used and by the ease of self-administration. This prospective, controlled, randomised, parallel group open label, multicenter, phase III, equivalence study has been aimed to compare the clinical effectiveness (in terms of oocytes obtained) and tolerability of subcutaneous (s.c.) self-administered versus classical intramuscular (i.m.) injections of Merional, a new highly-purified hMG preparation.

METHODS

A total of 168 normogonadotropic women undergoing IVF were enrolled. Among them, 160 achieved pituitary suppression with a GnRH-agonist long protocol and were randomised to MOS treatment with Merional s.c. or i.m. They started MOS with a standard hMG dose between 150-300 IU, depending upon patient's age, and underwent a standard IVF procedure.

RESULTS

No statistically significant difference in the mean number of collected oocytes (primary endpoint) was observed between the two study subgroups (7.46, SD 4.24 vs. 7.86, SD 4.28 in the s.c. and i.m. subgroups, respectively). As concerns the secondary outcomes, both the pregnancy and the clinical pregnancy rates were comparable between subgroups. The incidence of adverse events was similar in the two groups (2.4% vs. 3.7%, respectively). Pain at injection site was reported only the i.m. group (13.9% of patients).

CONCLUSION

Merional may be used by s.c. injections in IVF with an effectiveness in terms of retrieved oocytes that is equivalent to the one obtained with i.m administration and with a better local tolerability. With the limitations due to the sample size af this study, s.c. and i.m. administration routes seem to have the same overall safety.

The problem of IVF cost in developing countries: has natural cycle IVF a place?

Infertility represents a national health problem in some African countries. Limited financial health resources in developing countries are a major obstacle facing infertility management. IVF is the definitive line of treatment for many couples. Stimulation cycles are associated with risks of ovarian hyperstimulation syndrome and multiple pregnancy. This study evaluates the client acceptability of stimulated versus natural cycle IVF among couples attending one infertility clinic, with respect to cost and pregnancy outcome. Of the patients who were indicated for IVF, 15% (16/107) cancelled, due mostly (12/16, 75%) to financial reasons. The majority of patients who completed their IVF treatment (82/91, 90.1%) felt the price of the medical service offered was high, and 68.1% (62/91) accepted the idea of having cheaper drugs with fewer side effects but with possibly lower chances of pregnancy. Natural cycle IVF has emerged as a potential option that might be suitable for patients worldwide, especially in developing countries.

Natural cycle as first approach in aged patients with elevated follicle-stimulating hormone undergoing intracytoplasmic sperm injection: a pilot study

BACKGROUND

Poor ovarian response to standard in vitro fertilization-embryo transfer (IVF-ET) protocols or different regimens of treatment, as consequence of a diminished ovarian reserve, correlates strictly with patient age, elevated follicle-stimulating hormone (FSH) and reduced antral follicle count. The aim of the present pilot study was to evaluate the outcome of patients with poor prognostic features undergoing IVF-ET with natural cycles as a first approach and not as a consequence of a previous failure treatment.

MATERIALS AND METHODS

Eighteen aged patients (mean +/- standard deviation 40.2 +/- 0.7 years, range 37-43 years) with elevated serum FSH and reduced antral follicle count underwent intracytoplasmic sperm injection (ICSI) after spontaneous ovulation.

RESULTS

A total of 26 natural cycles with ICSI were analyzed. Pregnancy was observed in three patients, of which two were ongoing as assessed by fetal heart beat at ultrasound scan performed 4-5 weeks after ET.

CONCLUSION

The overall pregnancy rates achieved (11.5% per cycle, 20.0% per ET) are comparable with those of conventional IVF-ET in aged patients, and not impaired by a single embryo transferred. Better embryo quality, as a consequence of natural selection of oocytes, better endometrium receptivity and monthly repeatability of the procedure, can balance the relatively low chance to perform ET.