Endometrial receptivity in the light of modern assisted reproductive technologies

Enhancing Endometrial Health in Assisted Reproductive Technology (ART): Evaluating Autologous Endometrial Cells and Platelets-Rich Plasma (PRP) via Hysteroscopic Injections

This review article examines the effectiveness of incorporating autologous endometrial cells and platelet-rich plasma (PRP) through hysteroscopic injections within the field of assisted reproductive technology (ART). This study assesses the outcomes of these injections on the susceptibility of the endometrium, the dynamics of the uterus, and the frequencies of pregnancy in individuals with refractory thin endometrium. Based on a complete examination of several trials, it becomes apparent that autologous PRP injections provide encouraging turnouts in augmenting endometrial thickness, raising endometrial receptivity, and, in the end, raising chances of being pregnant and successful delivery. The research highlights the promise of autologous PRP and minimally changed endometrial cellular treatments in enhancing outcomes in ART, especially for people who have had problems with implantation. This article gives a whole evaluation of the medical use of and upgrades regarding the utilization of infusions of PRP and autologous endometrial cells under hysteroscopic control to deal with infertility issues related to endometrial health through the synthesis of contemporary studies.

Juvenile idiopathic arthritis

Juvenile idiopathic arthritis (JIA) is an umbrella term for arthritis of unknown origin, lasting for >6 weeks with onset before 16 years of age. JIA is the most common chronic inflammatory rheumatic condition of childhood. According to the International League Against Rheumatism (ILAR) classification, seven mutually exclusive categories of JIA exist based on disease manifestations during the first 6 months of disease. Although the ILAR classification has been useful to foster research, it has been criticized mainly as it does not distinguish those forms of chronic arthritis observed in adults and in children from those that may be unique to childhood. Hence, efforts to provide a new evidence-based classification are ongoing. Similar to arthritis observed in adults, pathogenesis involves autoimmune and autoinflammatory mechanisms. The field has witnessed a remarkable improvement in therapeutic possibilities of JIA owing to the availability of new potent drugs and the possibility to perform controlled trials with support from legislative interventions and large networks availability. The goal of drug therapy in JIA is to rapidly reduce disease activity to inactive disease or clinical remission, minimize drug side effects and achieve a quality of life comparable to that of healthy peers. As JIA can influence all aspects of a child's and their family's life, researchers increasingly recognize improvement of health-related quality of life as a key treatment goal.

Efficiency and safety of laser-assisted hatching on vitrified-warmed blastocyst transfer cycles: a prospective control trial

To clarify the efficiency and safety of laser-assisted hatching (LAH) application on vitrified-warmed blastocyst transfer (VBT) cycles, we designed the non-randomized concurrent control trial included 4039 VBT cycles in the Center for Reproductive Medicine, Cheeloo College of Medicine, Shandong University, during the even days from November 2014 to December 2015. The VBT cycles were divided into LAH group (n = 1932) and non-LAH group (n = 2107) according to the date of blastocyst thawing. Laser-partial zona pellucida dissection was performed on all blastocysts thawed on that day every 4 days, and those blastocysts were assigned to the LAH group. There were a higher biochemical pregnancy rate (66.87% vs 63.69%; P = 0.034; rate ratio for LAH vs non-LAH group [RR], 1.050; 95% confidence interval [CI], 1.004-1.098) and an increased live birth rate (48.81% vs 45.51%; P = 0.036; RR, 1.072; 95% CI, 1.005-1.145) with comparable ectopic pregnancy, twin or multiple pregnancies, spontaneous abortion and birth defect rates of the LAH group than those of the non-LAH group. Subgroup analysis showed that live birth rate, birth defect rate, and other pregnancy outcomes were comparable for patients younger than 35 years when blastocyst transfer, patients with endometrium thickness less than 0.9 cm during ovulation or the initiation of progesterone treatment, ICSI blastocysts, AC or BC blastocysts according to Gardner morphological criteria and day 5 blastocysts of the LAH group than it of non-LAH group. LAH could be performed selectively on vitrified-warmed blastocysts before transfer for better pregnancy outcomes. Trial registration number: ChiCTR2000032975. Date of registration: May 17, 2020. Retrospectively registered.

In the secretory endometria of women, luminal epithelia exhibit gene and protein expressions that differ from those of glandular epithelia

OBJECTIVE

To characterize the transcriptome of luminal epithelia (LE) of fertile secretory endometria and compare the results with those from glandular epithelia (GE).

DESIGN

Endometrial samples were collected at 2 and 7 days after initial blood LH surge in separate menstrual cycles. LE were obtained with the use of laser microdissection. mRNA was amplified with the use of linear polymerase chain reaction and hybridized to Agilent 4×44 microarrays. Gene analysis was used to identify differentially expressed mRNAs. Immunohistochemistry was used to assess nine proteins.

SETTING

One IVF clinic.

PATIENT(S)

Seven Caucasian fertile cycling women.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Cycle dating with the use of blood endocrinologic markers, microarrays of laser-microdissected LE, immunohistochemical analysis.

RESULT(S)

One hundred sixty-one (of 401) differentially expressed mRNAs in LE were identified from the metabolism pathway. Increased selective protein expression in LE at 7 days after initial LH surge was observed. LE mRNA expression was the converse of that in GE. The two cell types each had a different significant biologic pathway identified.

CONCLUSION(S)

Our results introduce a new concept that LE differentially expressed mRNAs are in the converse direction to that of GE, indicating different biologic processes despite the GE being continuous with the luminal monolayer. This probable distinction of biologic roles has not been noted previously. Further investigations must take cognizance of this observation.

Effects of variations in serum estradiol concentrations on secretory endometrial development and function in experimentally induced cycles in normal women

Eighteen normal women underwent pituitary down-regulation with leuprolide, followed by a 10-day treatment with 0.2 mg/d transdermal estradiol (E(2)) with subsequent allocation to one of two 10-day estradiol regimens plus 40 mg daily intramuscular P: supraphysiologic (0.2 mg/d transdermal E(2) mg/d vaginal micronized E(2)) or subphysiologic (no exogenous E(2) treatment). Average E(2) and P in the supraphysiologic, physiologic, and subphysiologic groups were 1,175.9 pg/mL and 17.5 ng/mL, 136.9 pg/mL and 21.2 pg/mL, and 23.8 ng/mL and 22.0 ng/mL, respectively, and there were no differences between groups in endometrial histology or expression of biomarkers of receptivity.

Integrins in the endometrium

The endometrium expresses many of the same integrins displayed by other tissues. Endometrial epithelial cells maintain the ‘classic’ epithelial integrins, including α2, α3, α6, and β4, while the stroma expresses the fibronectin receptor, α5β1. During the menstrual cycle, the endometrium undergoes dynamic changes in morphology in preparation for implantation. With these histological changes are concomitant alterations in integrin expression that appear to ‘frame’ the window of implantation, by the co-expression of glandular αvβ3 and α4β1 during days 20 to 24 of the menstrual cycle. The changes in integrin expression shift from epithelial to stroma predominance late in the menstrual cycle, extending into early pregnancy. Decidual integrins that appear upregulated in pregnancy include α1β1, α3β1, α6β1 and αvβ3. Markers of uterine receptivity hold promise for a better understanding of the implantation process and may help to explain many different types of infertility. These markers will be essential for monitoring and improving infertility therapies. The importance of integrins in the human endometrium now seems well established and promises to be an area of great clinical and basic science activity in the future.

Effects of assisted hatching method and age on implantation rates of IVF and ICSI

The objective of this study was to investigate whether a change in assisted hatching (AH) technique from total to partial penetration of the zona pellucida improved the outcome of IVF and intracytoplasmic sperm injection cycles where AH was indicated. This was an observational study conducted from the beginning of January 2000 to the end of April 2005. Total AH was performed in 312 cycles, while partial AH was performed in 592 cycles. In women of all ages, implantation, clinical pregnancy and live birth rates were higher in the partial AH group than in the total AH group (12.6 versus 7.2%, P = 0.0001; 22.3 versus 15.7%, P = 0.02; 18.2 versus 12.5%, P = 0.03 respectively). The benefit of partial AH was most marked in women under 38 years old (i.e. the recurrent implantation failure group). The authors conclude that partial AH is associated with higher implantation and pregnancy rates than total AH, especially in women under 38 years old who suffer from recurrent implantation failure.

Endometrial and subendometrial perfusion are impaired in women with unexplained subfertility

BACKGROUND

We used three-dimensional power Doppler angiography (3D-PDA) to examine the periodic changes in endometrial development and subendometrial vascularity during the normal menstrual cycle in 29 women with unexplained subfertility and 19 controls.

METHODS

3D-PDA was performed on alternate days from day 3 of the cycle until ovulation and then every 4 days until menses. VOCAL (Virtual Organ Computer-aided AnaLysis) and shell-imaging were used to define and to quantify the power Doppler signal within the endometrial and subendometrial regions producing indices of their relative vascularity.

RESULTS

Women with unexplained subfertility demonstrated significant changes with time (P<0.001) in the indices of vascularity within the endometrium and subendometrium during the menstrual cycle characterized by a pre-ovulatory peak and post-ovulatory fall. These changes mirrored those observed in the control group but were significantly reduced in the endometrium and subendometrium during the mid-late follicular phase and early luteal phase. There were no differences in endometrial thickness or volume between the groups or in the plasma concentrations of estradiol or progesterone.

CONCLUSIONS

Endometrial and subendometrial vascularity are significantly reduced in women with unexplained subfertility during the mid-late follicular phase irrespective of estradiol or progesterone concentrations and endometrial morphometry.

Osteopontin: roles in implantation and placentation

Osteopontin (OPN) is an acidic member of the small integrin-binding ligand N-linked glycoprotein (SIBLING) family of extracellular matrix proteins/cytokines that undergoes extensive posttranslational modification, including phosphorylation, glycosylation, and cleavage, yielding molecular mass variants ranging in size from 25 to 75 kDa. The result is a versatile protein(s) with multiple functions arising from its role as a mediator of cell-cell and cell-extracellular matrix (ECM) communication that encompass both normal and tumorigenic developmental processes, immunological responses during inflammation and wound healing, and biomineralization. Studies in primates, pigs, sheep, and rodents have revealed that OPN is a major constituent of the uterine-placental microenvironment with influence as 1) a component of histotroph required for adhesion and signal transduction at the uterine-placental interface throughout pregnancy, 2) a gene product expressed by uterine stroma contributing to a decidualization-like transformation that correlates with the degree of conceptus invasiveness, and 3) a product of resident uterine and placental immune cells that may regulate their behavior and cytokine production. This minireview summarizes information regarding uterine and placental expression of OPN that has accumulated over the past 15 yr, and we briefly describe structural/functional properties of this protein that are likely relevant to its role(s) during pregnancy. Comparative studies have offered insights into the potential hormonal/cytokine, cellular, and molecular mechanisms underlying OPN-mediated adhesion, remodeling, and cell-cell/cell-ECM communication within the uterus and placenta. OPN has the potential to profoundly impact pregnancy, and investigators are now challenged to focus on the mechanistic nature of the functions of this multifaceted and major component of the uterine-placental microenvironment.

Differences in glycosylation and sperm-egg binding inhibition of pregnancy-related glycodelin

Glycodelin is a glycoprotein produced in many glands, particularly those of reproductive tissues. It appears as different glycoforms in amniotic fluid (glycodelin-A) and seminal plasma (glycodelin-S), but only glycodelin-A inhibits gamete adhesion. In the present study, glycodelin from secretory-phase endometrium, first-trimester pregnancy decidua, and midtrimester amniotic fluid was studied with respect to physicochemical properties, including glycosylation patterns and inhibitory activity of sperm-egg binding. Purified glycodelins from all these sources were similar in isoelectric focusing and in lectin immunoassays using lectins from Wisteria floribunda and Sambucus nigra. Likewise, the glycodelins inhibited sperm-egg binding in a dose-dependent manner, as measured by hemizona-binding assay. However, subtle quantitative physicochemical and biological differences were found between glycodelins from different sources as well as within the same tissue/fluid between different individuals. Differences were most pronounced between endometrial glycodelins from nonpregnancy and first-trimester pregnancy. The glycan structures studied by fast-atom bombardment mass spectrometry of individual amniotic fluid glycodelin-A samples also showed interindividual quantitative differences. In conclusion, glycodelins from different female reproductive tract tissues and amniotic fluid share substantial similarity, allowing all of them to be called glycodelin-A. However, these glycodelins exhibit quantitative physicochemical and functional differences between different sources and individuals.

Routine laser assisted hatching results in significantly increased clincal pregnancies

PURPOSE

To elucidate the appropriateness of current indications for assisted hatching (AH) in cleavage stage human embryos and to confirm our preliminary findings that only young patients (about 67%) benefit from AH.

METHODS

Prior to transfer, 2 of 3 embryos selected for ET were subjected to laser assisted hatching (LAH). Control group consisted of patients matched by similar characteristics and protocol except LAH was not performed.

RESULTS

The clinical pregnancy rate in women < or = 36 years was 64.9% (24/37) for embryos subjected to LAH but was significantly lower (p = 0.029) in the control (33.3%; 10/30). The implantation rate in women < or = 36 years in the test group was 38.1% (40/105) that was significantly higher than that of the control group (17.5%, 14/80; p = 0.0039).

CONCLUSIONS

LAH is beneficial for women < or = 36 years but not for women > or = 37 years, for embryos with thin zonae (< or = 16 micron) but not with thick zonae (> or = 17 micron), and for those with repeated failures (37-50%).

Ultrasonography as a predictor of embryo implantation after in vitro fertilization: a controlled study

OBJECTIVE

To investigate the predictive value of ultrasonographic parameters as prognostic indicators of implantation after IVF when measured on the day of embryo transfer.

DESIGN

Comparative, observational study.

SETTING

University teaching hospital.

PATIENT(S)

Two hundred eighty patients undergoing IVF.

INTERVENTION(S)

Ovarian stimulation, IVF.

MAIN OUTCOME MEASURE(S)

Variables related to patients' clinical characteristics, treatment characteristics, ovarian response, ovum retrieval, outcome of IVF and ICSI, embryo transfer, ultrasonographic and Doppler endometrial measurements, and uterine blood flow that have been proposed as potential predictive factors of implantation. All transvaginal ultrasonographic assessments were performed on the day of embryo transfer.

RESULT(S)

Among 240 patients finally evaluable, 67 (group 1) became pregnant after IVF, and 173 (group 2) failed to conceive. The 111 nonpregnant patients who had the same embryo score per replacement (group 3) as did patients in group 1 were selected for comparison purposes. The only significant differences between groups 1 and 3 were the type A endometrium and the absence of a protodiastolic notch in the uterine arteries, both of which were more frequently found in group 1. However, a considerable overlap existed between conception and nonconception cycles regarding both variables.

CONCLUSION(S)

Ultrasonographic parameters as predictors of implantation in assisted reproduction have a limited value in the clinical setting.

Adjuvant L-arginine treatment in controlled ovarian hyperstimulation: a double-blind, randomized study

BACKGROUND

Enhanced vascularization appears to be important for follicular selection and maturation in both spontaneous and stimulated IVF cycles. Nitric oxide, formed in vivo from L-arginine, may play a key role in follicular maturation and ovulation.

METHODS

To evaluate the role of L-arginine supplementation in controlled ovarian hyperstimulation, 37 IVF patients were divided into two groups according to ovarian stimulation protocols: group I, GnRH agonist plus pure (p)FSH plus oral L-arginine (n = 18); and group II, GnRH agonist plus pFSH plus placebo (n = 19). Hormonal, ultrasonographic and Doppler evaluations were performed, and plasma and follicular fluid nitrite/nitrate concentrations were monitored.

RESULTS

Thirty-two patients completed the study. In group I (n = 16), plasma L-arginine concentrations increased from (basal) 87 +/- 12 micromol to 279 +/- 31 micromol (P = 0.002) on the day of beta-HCG administration. In this group, pFSH treatment was shorter (P = 0.039) than in group II (n = 16). The number of the follicles > or =17mm was lower (P = 0.038) in group I than group II. The "good quality" embryos were fewer in number (P = 0.034) and pregnancy rate, both per patient (P = 0.024) and per embryo transfer (P = 0.019), was lower in group I. In the L-arginine group, an increased follicular fluid concentration of nitrite/nitrate was observed. On day 8 of the cycle, elevated plasma estradiol levels were associated with decreased blood flow resistances of perifollicular arteries. Follicular fluid concentrations of nitrite/nitrate were inversely correlated with embryo quality (r = -0.613; P = 0.005) and perifollicular artery pulsatility index (r = -0.609; P = 0.021).

CONCLUSIONS

L-Arginine supplementation may be detrimental to embryo quality and pregnancy rate during controlled ovarian hyperstimulation cycles.

On the mechanisms of action of short-term levonorgestrel administration in emergency contraception

The effects of short-term administration of levonorgestrel (LNG) at different stages of the ovarian cycle on the pituitary-ovarian axis, corpus luteum function, and endometrium were investigated. Forty-five surgically sterilized women were studied during two menstrual cycles. In the second cycle, each women received two doses of 0.75 mg LNG taken 12 h apart on day 10 of the cycle (Group A), at the time of serum luteinizing hormone (LH) surge (Group B), 48 h after positive detection of urinary LH (Group C), or late follicular phase (Group D). In both cycles, transvaginal ultrasound and serum LH were performed from the detection of urinary LH until ovulation. Serum estradiol (E2) and progesterone (P(4)) were measured during the complete luteal phase. In addition, an endometrial biopsy was taken at day LH + 9. Eighty percent of participants in Group A were anovulatory, the remaining (three participants) presented significant shortness of the luteal phase with notably lower luteal P4 serum concentrations. In Groups B and C, no significant differences on either cycle length or luteal P4 and E2 serum concentrations were observed between the untreated and treated cycles. Participants in Group D had normal cycle length but significantly lower luteal P4 serum concentrations. Endometrial histology was normal in all ovulatory-treated cycles. It is suggested that interference of LNG with the mechanisms initiating the LH preovulatory surge depends on the stage of follicle development. Thus, anovulation results from disrupting the normal development and/or the hormonal activity of the growing follicle only when LNG is given preovulatory. In addition, peri- and post-ovulatory administration of LNG did not impair corpus luteum function or endometrial morphology.

Laser zona pellucida thinning--an alternative approach to assisted hatching

BACKGROUND

The purpose of this study was to assess the efficacy and hatching characteristics of in-vitro cultured human embryos subjected to laser zona pellucida thinning.

METHOD

Zona thinning was performed on 110 embryos using a non-contact 1.48 microm diode laser and the hatch rate in vitro was compared with 42 control embryos. Variation of zona thickness and degree of zona expansion was assessed. Scanning electron microscopy was performed on embryos entrapped during hatching to identify the site of hatching.

RESULTS

The rate of hatching was significantly higher in laser thinned blastocysts compared with control embryos (68 versus 33% respectively, P < 0.01). Laser thinning increased the variation of zona thickness in embryos from 11.6-27.3%. Natural zona thinning occurred in 92% of laser thinned hatching blastocysts and 100% of control embryos.

CONCLUSION

These results suggest that laser zona thinning is effective and may provide significant advantages over conventional assisted hatching techniques, which create holes.

Use of integrins to date the endometrium

OBJECTIVE

To compare traditional histologic dating criteria of the endometrium with immunohistochemical criteria based on epithelial integrin expression during the menstrual cycle.

DESIGN

Prospective clinical study.

SETTING

An academic teaching hospital.

PATIENT(S)

Fertile and infertile women undergoing endometrial biopsy.

MAIN OUTCOME MEASURE(S)

Immunohistochemical staining intensity and distribution (HSCORE) of three integrins and traditional histologic endometrial dating.

RESULT(S)

In 1,501 endometrial specimens, phase assignment-based integrin staining was 95% and 85% concordant with histology for the proliferative and early secretory phase, respectively, but only 54% and 49% concordant for the middle and late secretory phase, respectively. The greatest disagreement occurred during the midluteal phase. Of 1,090 patients who underwent sampling 6-10 days after detection of a urinary LH surge (corresponding to cycle days 20-24), multiple logistic regression analysis revealed that endometriosis was positively correlated and male factor infertility was negatively correlated with absent beta3 integrin subunit expression. Diagnosis and absent epithelial alpha4beta1 expression were not related. Patient age was not correlated with the incidence of abnormalities in integrin expression.

CONCLUSION(S)

Traditional histologic dating of the endometrium has remained the gold standard for nearly 50 years. Although the use of marker proteins provides additional information and may reflect endometrial function or receptivity, such markers cannot yet replace traditional methods of endometrial assessment.

Ultrasound-guided soft catheter embryo transfers will improve pregnancy rates in in-vitro fertilization

Attempts to improve clinical pregnancy rates after in-vitro fertilization (IVF) and embryo transfer are constantly being made. Two changes in technique of embryo transfer of potential clinical importance were evaluated over two contiguous time periods in order to observe any corresponding change in clinical pregnancy (CP) rate per transfer: (i) embryo transfer catheter; (ii) ultrasound guidance. Catheter choices were hard: Tefcat, Tom Cat, or Norfolk; or soft: Frydman or Wallace. Ultrasound visualization was considered to be excellent/good when the catheter could be followed from the cervix to the fundus by transabdominal ultrasound with retention of the embryo-containing fluid droplet; fair/poor if visualization could not document the sequence of events. Embryo transfers were performed in 518 cycles. CP rates per transfer using soft and hard catheters was 36 and 17% (P < 0.000) respectively. CP rates per transfer for transfers performed with and without ultrasound guidance were 38 and 25% (P < 0.002) respectively. A statistically significant difference was also noted when visualization ranks were compared. CP rates per transfer in all excellent/good ultrasound-guided transfers was 41.5 versus 16.7% for fair/poor transfers (P < 0.038). In conclusion, performance of embryo transfer with a soft catheter under ultrasound guidance with good visualization resulted in a significant increase in clinical pregnancy rates.

Adjuvant L-arginine treatment for in-vitro fertilization in poor responder patients

The objective of the present study was prospectively and randomly to evaluate the role of L-arginine in improving uterine and follicular Doppler flow and in improving ovarian response to gonadotrophin in poor responder women. A total of 34 patients undergoing assisted reproduction was divided in two groups according to different ovarian stimulation protocols: (i) flare-up gonadotrophin-releasing hormone analogue (GnRHa) plus elevated pure follicle stimulating hormone (pFSH) (n = 17); and (ii) flare-up GnRHa plus elevated pFSH plus oral L-arginine (n = 17). During the ovarian stimulation regimen, the patients were submitted to hormonal (oestradiol and growth hormone), ultrasonographic (follicular number and diameter, endometrial thickness) and Doppler (uterine and perifollicular arteries) evaluations. Furthermore, the plasma and follicular fluid concentrations of arginine, citrulline, nitrite/nitrate (NO2-/NO3-), and insulin-like growth factor-1 (IGF-1) were assayed. All 34 patients completed the study. In the L-arginine treated group a lower cancellation rate, an increased number of oocytes collected, and embryos transferred were observed. In the same group, increased plasma and follicular fluid concentrations of arginine, citrulline, NO2-/NO3-, and IGF-1 was observed. Significant Doppler flow improvement was obtained in the L-arginine supplemented group. Three pregnancies were registered in these patients. No pregnancies were observed in the other group. It was concluded that oral L-arginine supplementation in poor responder patients may improve ovarian response, endometrial receptivity and pregnancy rate.

The luteal phase of cycles utilizing controlled ovarian hyperstimulation and the possible impact of this hyperstimulation on embryo implantation

OBJECTIVE

Our purpose was to evaluate the early luteal phase of assisted reproductive cycles utilizing controlled ovarian hyperstimulation and to compare these results with those obtained in unstimulated cycles.

STUDY DESIGN

We undertook a descriptive study analyzing luteal phase serum progesterone levels, endometrial histologic features, and endometrial surface ultrastructure by scanning electron microscopy of cycles utilizing controlled ovarian hyperstimulation. Study samples were obtained from 7 oocyte donors undergoing controlled ovarian hyperstimulation for the purpose of follicle aspiration in oocyte donation. Control (unstimulated) serum progesterone samples were obtained from 19 patients undergoing in vitro fertilization in unstimulated cycles. Prospective recipients of oocyte donation (n = 20) undergoing mock cycles of exogenous estradiol and progesterone acted as controls for the endometrial biopsies.

RESULTS

Serum progesterone levels on the day of human chorionic gonadotropin administration were twofold higher in the study group than in the unstimulated group (1.1 +/- 0.6 vs 0.5 +/- 0.2 ng/ml, mean +/- SD, p < 0.01). On the day of follicle aspiration, progesterone levels were much higher in the study group (8.5 +/- 2.2 vs 0.5 +/- 0.1 ng/ml, p < 0.001). Histologic dating of endometrial biopsies revealed that the study group was advanced by nearly 2 days as compared with the group having artificial cycles. Pinopods, ultrastructural markers of the implantation window, were present in only one of seven study cycles as compared with all of the four artificial cycles.

CONCLUSIONS

The early luteal phase of cycles undergoing controlled ovarian hyperstimulation is characterized by markedly elevated serum progesterone levels during the periovulatory period, advanced endometrial histologic features, and an absence of endometrial pinopods at the time of embryo implantation. We speculate that these high levels of progesterone in the early luteal phase cause premature endometrial luteinization and a premature appearance of the implantation window, thus providing an explanation for the observed decrease in endometrial receptivity.

Effects of clomiphene citrate on the endometrial thickness and echogenic pattern of the endometrium

OBJECTIVE

To study the effects of clomiphene citrate (CC) on the endometrium by ultrasound and to reveal the echogenic difference between the control cycle and the CC cycle.

DESIGN

Retrospective study of patients before and during a CC treatment.

SETTING

Department of Obstetrics and Gynecology, Yamaguchi University School of Medicine, Ube, Yamaguchi, Japan.

PATIENT(S)

Seventy-nine infertile women who had a spontaneous ovulation and a normal luteal function.

INTERVENTION(S)

Patients received 50 mg/d CC between days 5 and 9 of the menstrual cycle.

MAIN OUTCOME MEASURE(S)

Endometrial thickness, echogenic pattern of the endometrium, serum E2 content, and E2 and P receptor contents in the endometrium.

RESULT(S)

Endometrial thickness was significantly thinner during the CC cycle (7.6 +/- 1.4 mm, mean +/- SD, n = 79) than during the control cycle (8.5 +/- 1.7 mm, n = 79) on late proliferative days, but there was no significant difference on midsecretory days (10.8 +/- 2.2 mm during the CC cycle, n = 79; 11.2 +/- 2.2 mm during the control cycle, n = 79). The echogenic patterns, however, were different between the two cycles on midsecretory days. Moreover, the incidence in which patients showed a grade 3 endometrium on midsecretory days was significantly higher during the conceived CC cycle compared with the not-conceived CC cycle. Serum E2 levels were significantly higher, but E2 receptor contents in the endometrium were significantly lower during the CC cycle (67 +/- 46 fmol/mg, n = 13) compared with the control cycle (123 +/- 89 fmol/mg, n = 15) on late proliferative days.

CONCLUSION(S)

Clomiphene citrate affected the echogenic pattern of the endometrium, and most of the endometrium showed a grade 3 pattern on midsecretory days during the conceived CC cycle. Under the CC treatment, the comfortable endometrium for embryos might be different from the control cycle.

Transvaginal Doppler study of uterine artery blood flow in in vitro fertilization-embryo transfer cycles

OBJECTIVE

To verify whether uterine artery impedance, measured as pulsatility index and resistance index is related to the outcome of in IVF-ET cycles.

DESIGN

Prospective study of infertile women participating in an IVF-ET program.

SETTING

University Hospital.

PATIENTS

Two hundred women (24 to 40 years of age), who had one to three good quality embryos transferred to the uterus after a standardized IVF cycle.

INTERVENTION

Transvaginal color Doppler and a blood sample on the day of ET.

MAIN OUTCOME MEASURES

Uterine artery pulsatility index and resistance index, endometrial thickness, serum E2 and P concentrations, clinical pregnancy rate (PR).

RESULTS

Pulsatility indices and resistance indices were lower in conception (2.45 +/- 0.54 and 0.85 +/- 0.04, respectively) than in nonconception cycles (2.66 +/- 0.39 and 0.87 +/- 0.04, respectively), although the overlap of the values is considerable. Overall PR was 35% per ET, and it decreased significantly when pulsatility index was > 3.0 (15%) and resistance index > 0.92 (13%), being lowest when pulsatility index was > 3.3 and resistance index > 0.95 (10%). Such a high impedance was detected in 9% of nonconception cycles.

CONCLUSION

In IVF-ET cycles the uterus is likely to be unreceptive when uterine artery pulsatility index is > 3.3 and resistance index > 0.95 before ET, but this occurs only in 9% of the cycles.

Luminal and glandular endometrial epithelium express integrins differentially throughout the menstrual cycle: implications for implantation, contraception, and infertility

PROBLEM

Integrins belong to a family of cell adhesion molecules that are present on virtually all cells. The temporal and spatial expression of these important proteins on the human endometrium suggests that certain integrins may participate in the cascade of molecular events leading to successful implantation.

METHODS

Using immunohistochemistry, we studied the expression of 12 different integrins in up to 600 samples of human endometrium throughout the menstrual cycle. Intensity and distribution of staining was determined using the semiquantitative HSCORE, with specific focus on the differences between glandular and luminal expression.

RESULTS

We noted that the glandular and luminal epithelium undergo independent alterations in integrin expression throughout the menstrual cycle. Specifically, glandular epithelium express certain integrins only during the window of implantation, while luminal epithelium down-regulate certain integrins during this time. The expression of one integrin (the alpha v beta 3 vitronectin receptor) on both luminal and glandular epithelium coincides with the time of embryo attachment; aberrant expression of this integrin is associated with infertility.

CONCLUSION

It appears that the endometrium is a unique tissue with regard to the number of integrins that undergo temporal and spatial changes during the menstrual cycle. These data may offer new directions for the development of a novel contraceptive approach targeted to the endometrium as well as a better understanding of occult causes of infertility in women.

Comparison of transdermal versus oral estradiol on endometrial receptivity

OBJECTIVE

To compare the effects of oral micronized E2 with transdermal E2 on endometrial receptivity in women undergoing oocyte donation.

DESIGN

Prospective, randomized, crossover trial. Serum E2 and P concentrations were measured on cycle days 14 and 22 (luteal day +8). Endometrial biopsies were obtained on day 22 and read in a blinded fashion for histology and beta-3-integrin expression.

SETTING

University-based donor oocyte program.

PATIENTS

Twenty-seven patients presenting for donor oocytes.

MAIN OUTCOME MEASURES

Endometrial histology and beta-3-integrin expression.

RESULTS

The endometrial glandular histology in women given oral micronized E2 was delayed by a mean of 1.6 days in comparison to that of women given transdermal E2. Seventy percent of women given oral E2 displayed a lag > or = 4 days whereas 29.6% given transdermal E2 displayed a similar lag. Serum E2 levels were 1,194 +/- 108.8 pg/mL (mean +/- SEM; conversion factor to SI unit, 3.671) in women on oral micronized E2 and 117.4 +/- 14.0 pg/mL in those on transdermal E2.

CONCLUSION

The supraphysiologic serum E2 levels associated with oral micronized E2 may have a deleterious impact on endometrial receptivity. The development of more physiologic hormone replacement protocols may enhance endometrial receptivity and lead to improved clinical pregnancy rates.