Levels of vascular endothelial growth factor are elevated in patients with ectopic pregnancy: is this a novel marker?

Nanomedicines for Improved Management of Ectopic Pregnancy: A Narrative Review

Ectopic pregnancy (EP) - the implantation of an embryo outside of the endometrial cavity, often in the fallopian tube - is a significant contributor to maternal morbidity and leading cause of maternal death due to hemorrhage in first trimester. Current diagnostic modalities including human chorionic gonadotropin (hCG) quantification and ultrasonography are effective, but may still misdiagnose EP at initial examination in many cases. Depending on the patient's hemodynamic stability and gestational duration of the pregnancy, as assessed by history, hCG measurement and ultrasonography, management strategies may include expectant management, chemotherapeutic treatment using methotrexate (MTX), or surgical intervention. While these strategies are largely successful, expectant management may result in tubal rupture if the pregnancy does not resolve spontaneously; MTX administration is not always successful and may induce significant side effects; and surgical intervention may result in loss of the already-damaged fallopian tube, further hampering the patient's subsequent attempts to conceive. Nanomaterial-based technologies offer the potential to enhance delivery of diagnostic imaging contrast and therapeutic agents to more effectively and safely manage EP. The purpose of this narrative review is to summarize the current state of nanomedicine technology dedicated to its potential to improve both the diagnosis and treatment of EP.

Untargeted Metabolomic Biomarker Discovery for the Detection of Ectopic Pregnancy

Ectopic pregnancy (EP) is the leading cause of maternal morbidity and mortality in the first trimester. Using an untargeted metabolomic approach, we sought to identify putative plasma biomarkers using tandem liquid chromatography-mass spectrometry for the detection of tubal EP. This case-control study included the prospective recruitment of 50 tubal EP cases and 50 early intrauterine pregnancy controls. To avoid over-fitting, logistic regression models were developed in a randomly selected discovery group (30 cases vs. 30 controls) and validated in the test group (20 cases vs. 20 controls). In total, 585 mass spectral features were detected, of which 221 molecular features were significantly altered in EP plasma (p < 0.05). Molecular networking and metabolite identification was employed using the Global Natural Products Social Molecular Networking (GNPS) database, which identified 97 metabolites at a high confidence level. Top significant metabolites include subclasses of sphingolipids, carnitines, glycerophosphocholines, and tryptophan metabolism. The top regression model, consisting of D-erythro-sphingosine and oleoyl-carnitine, was validated in a test group and achieved an area under receiving operating curve (AUC) (95% CI) = 0.962 (0.910-1) with a sensitivity of 100% and specificity of 95.9%. Metabolite alterations indicate alterations related to inflammation and abnormal placentation in EP. The validation of these metabolite biomarkers in the future could potentially result in improved early diagnosis.

Evaluation of Different Doses of the Aromatase Inhibitor Letrozole for the Treatment of Ectopic Pregnancy and Its Effect on Villous Trophoblastic Tissue

Letrozole, an aromatase inhibitor, has recently been introduced as a favorable medical treatment for ectopic pregnancy. We aimed at evaluating the effects of different doses of letrozole for termination of ectopic pregnancy and study their effects on villous trophoblastic tissue. Sixty patients with undisturbed ectopic pregnancy were classified into three equal groups. Group I: the control group that contained women who underwent laparoscopic salpingectomy, Group II: patients who received letrozole (5 mg day-1) for 10 days, and Group III: patients who received letrozole (10 mg day-1) for 10 days. Subsequently, the β-hCG levels were determined on the first day and after 11 days of treatment. Group IV consisted of patients of GII and GIII; their β-hCG did not drop below 100 mIU/ml within 11 days, and underwent salpingectomy. Placental tissues from patients undergoing salpingectomy either from the control group or GIV were processed for the evaluation of estrogen (ER) and progesterone (PR) receptors, vascular endothelial growth factor (VEGF), and cleaved caspase 3 (CC-3) expression. Cases exposed to high dose letrozole 10 mg day-1 resulted in a higher ectopic pregnancy resolution rate of 85% (17/20), while the resolution rate of the low dose letrozole-treated group (5 mg day-1) was 65% (13/20), and also showed a significant reduction in β-hCG levels on the 11th day, 25.63 ± 4.29 compared to the low dose letrozole group 37.91 ± 7.18 (P < 0.001), Meanwhile, the letrozole-treated group GIV showed markedly reduced expression of ER, PR, and VEGF and a significant increase in the apoptotic index cleaved caspase-3 compared to the control group (P < 0.001). The utilization of letrozole at a dose of 10 mg day-1 for medical treatment of ectopic pregnancy results in a high-successful rate without any severe side effects. Letrozole depriving the placenta of estrogen that had vascular supporting signals resulted in destroying the vascular network with marked apoptosis.

Serum vascular endothelial growth factor as a marker for tubal pregnancy

OBJECTIVE

The objective of this study was to evaluate whether a single measurement of vascular endothelial growth factor could distinguish between intrauterine pregnancy and ectopic pregnancy and to correlate the levels of vascular endothelial growth factor with serum levels of progesterone andβ-human chorionic gonadotropin in each subgroup.

METHODS

Ninety patients with a positive human chorionic gonadotropin test and either abdominal pain or vaginal bleeding were selected; pregnancies were singletons, spontaneously conceived, 42-56 days of gestational age. All patients had a transvaginal ultrasound examination and were divided into three subgroups: abnormal intrauterine pregnancy, tubal pregnancy, and normal intrauterine pregnancy. Tubal pregnancies were surgically treated and histologically confirmed. Blood samples were collected for the determination of β-human chorionic gonadotropin, progesterone, and vascular endothelial growth factor and their concentrations were compared in each subgroup. Receiver operating characteristic curve was calculated by comparing the subgroup of tubal pregnancy to the other groups. A Fisher discriminant function analysis was performed. The level of significance was 5%.

RESULTS

One-way analysis of variance revealed a significant correlation between the different subgroups and β-human chorionic gonadotropin, progesterone, and vascular endothelial growth factor serum levels (p<0.001). Vascular endothelial growth factor concentration was significantly higher for patients with tubal pregnancy than for other subgroups (p<0.05). β-Human chorionic gonadotropin and progesterone levels were higher in the subgroup with normal intrauterine pregnancies compared with the subgroups with tubal and abnormal intrauterine pregnancies (p<0.05). Serum vascular endothelial growth factor level >188.7 ng/mL predicted tubal pregnancy with 96.7% sensitivity, 95.0% specificity, 90.6% positive predictive value, and 98.3% negative predictive value.

CONCLUSIONS

Serum vascular endothelial growth factor could be a marker in discriminating intrauterine pregnancy from tubal pregnancy; its levels are increased in women with ectopic pregnancy compared with women with normal and abnormal intrauterine pregnancies.

Polymorphisms of vascular endothelial growth factor and recurrent implantation failure: a systematic review and meta-analysis

PURPOSE

To investigate the associations between polymorphisms of vascular endothelial growth factor (VEGF) with recurrent implantation failure (RIF).

METHODS

We performed the systematic review and meta-analysis by searching databases of PubMed, EMBASE, OVID, and CNKI (China National Knowledge Infrastructure) for studies that evaluated the associations between VEGF polymorphisms with RIF. Meta-analysis was performed if the polymorphism was studied by more than two case-control studies. Data were analyzed using R software. Odds ratios (ORs) with 95% confidence intervals (CIs) were reported to assess the associations.

RESULTS

Nine VEGF polymorphisms (-1154G > A, -460T > C, +405G > C, -7C > T, -634C > G, -2578C > A, +936C > T, 5C > T, -583C > T) were systematically reviewed. Meta-analysis was performed on VEGF -1154 G > A polymorphism. Three case-control studies consisted of 683 women were included in the quantitative meta-analysis (305 RIF patients and 378 controls). Results showed that VEGF -1154A allele was significantly associated with RIF (OR 1.39, 95% CI 1.08-1.78, P-value = 0.01). The dominant genetic model showed that VEGF 1154AA plus VEGF 1154AG genotypes were more frequent in RIF patients than VEGF 1154GG genotype (OR 1.56, 95% CI 1.10-2.20, P-value = 0.01). However, the result under the recessive genetic model showed no significant difference (OR 1.67, 95% CI 0.92-3.03, P-value = 0.09).

CONCLUSION

VEGF -1154A allele may serve as one of the predisposing factors of RIF. Women with VEGF 1154 AA/GA genotypes were at higher risk of RIF. However, we should consider the haplotype effect of VEGF polymorphisms in future studies.

Metabolomic identification of novel diagnostic biomarkers in ectopic pregnancy

INTRODUCTION

Ectopic pregnancy (EP) is a potentially life-threatening condition and early diagnosis still remains a challenge, causing a delay in management leading to tubal rupture.

OBJECTIVES

To identify putative plasma biomarkers for the detection of tubal EP and elucidate altered biochemical pathways in EP compared to intrauterine pregnancies.

METHODS

This case-control study included prospective recruitment of 39 tubal EP cases and 89 early intrauterine pregnancy controls. Plasma samples were biochemically profiled using proton nuclear magnetic resonance spectroscopy (¹H NMR). To avoid over-fitting, datasets were randomly divided into a discovery group (26 cases vs 60 controls) and a test group (13 cases and 29 controls). Logistic regression models were developed in the discovery group and validated in the independent test group. Area under the receiver operating characteristics curve (AUC), 95% confidence interval (CI), sensitivity, and specificity values were calculated.

RESULTS

In total 13 of 43 (30.3%) metabolite concentrations were significantly altered in EP plasma (p < 0.05). Metabolomic profiling yielded significant separation between EP and controls (p < 0.05). Independent validation of a two-metabolite model consisting of lactate and acetate, achieved an AUC (95% CI) = 0.935 (0.843-1.000) with a sensitivity of 92.3% and specificity of 96.6%. The second metabolite model (D-glucose, pyruvate, acetoacetate) performed well with an AUC (95% CI) = 0.822 (0.657-0.988) and a sensitivity of 84.6% and specificity of 86.2%.

CONCLUSION

We report novel metabolomic biomarkers with a high accuracy for the detection of EP. Accurate biomarkers could potentially result in improved early diagnosis of tubal EP cases.

Developing a deeper insight into reproductive biomarkers

The development of biomarkers of reproductive medicine is still in its infancy because many black boxes are still present in reproductive medicine. Novel approaches to human infertility diagnostics and treatment must be developed because reproductive medicine has lagged behind in the implementation of biomarkers in clinical medicine. Despite the dearth of the available literature, the current rapid pace of publications suggests that this gap will soon be filled therefore; this review is a précis of the research that has been done so far and will provide a basis for the development of biomarkers in reproductive medicine.

Serum concentration of vascular endothelial growth factor and depth of trophoblastic invasion in ampullary ectopic pregnancy

OBJECTIVE:

To evaluate the association between the depth of trophoblastic infiltration and serum vascular endothelial growth factorconcentration in patients with an ampullary pregnancy.

METHODS:

This prospective cross-sectionalstudy involved 34 patients with an ampullary ectopic pregnancy who underwent salpingectomy between 2012 and 2013. Maternal serum vascular endothelial growth factor concentrations were measured using Luminex technology. Trophoblastic invasion was classified histologically as follows: stage I, limited to the tubal mucosa; stage II, reaching the muscle layer; and stage III,involving the full thickness. The qualitative data were compared using Fisher's exact test. The nonparametric Kruskal-Wallis and Mann-Whitney tests were used to evaluate differences in serum vascular endothelial growth factor among the degrees of trophoblastic invasion. ROC curves were constructed to determine vascular endothelial growth factor cut-off values that predict the degree of tubal invasion based on the best sensitivity and specificity.

RESULTS:

Eight patients had stage I trophoblastic invasion, seven had stage II, and 19 had stage III. The median serum vascular endothelial growth factorconcentration was 69.88 pg/mL for stage I, 14.53 pg/mL for stage II and 9.08 pg/mL for stage III, with a significant difference between stages I and III. Based on the ROC curve, a serum vascular endothelial growth factor concentration of 25.9 pg/mL best differentiated stage I from stages II and III with asensitivity of 75.0%, specificity of 76.9%, and area under the curve of 0.798.

CONCLUSIONS:

The depth of trophoblastic penetration into the tubal wall isassociated with serum vascular endothelial growth factor concentration in ampullary pregnancies.

Ectopic pregnancy risk factors for ART patients undergoing the GnRH antagonist protocol: a retrospective study

BACKGROUND

In-vitro fertilization is a known risk factor for ectopic pregnancies. We sought to establish the risk factors for ectopic pregnancy in GnRH antagonist cycles examining patient and stimulation parameters with an emphasis on ovulation trigger.

METHODS

We conducted a retrospective, cohort study of 343 patients undergoing 380 assisted reproductive technology (ART) cycles with the GnRH antagonist protocol and achieving a clinical pregnancy from November 2010 through December 2015.

RESULTS

Significant risk factors for ectopic pregnancy in the univariate analysis included prior Cesarean section (CS), endometriosis, mechanical factor infertility, longer stimulation, elevated estradiol and progesterone levels, GnRH agonist trigger, higher number of oocytes aspirated, and insemination technique. Independent risk factors for ectopic pregnancy in the multivariate analysis included GnRH agonist trigger, higher number of oocytes aspirated, insemination technique, and prior Cesarean section.

CONCLUSION

Excessive ovarian response, IVF (as opposed to ICSI), prior Cesarean section and GnRH agonist trigger were found to be independent risk factors for ectopic pregnancy. Caution should be exercised before incorporating the GnRH agonist trigger for indications other than preventing OHSS. When excessive ovarian response leads to utilization of GnRH agonist trigger, strategies for preventing ectopic pregnancy, such as a freeze all policy or blastocyst transfer, should be considered. Further studies should elucidate whether adjusting the luteal support can reduce the ectopic pregnancy risk.

Prioritization of Susceptibility Genes for Ectopic Pregnancy by Gene Network Analysis

Ectopic pregnancy is a very dangerous complication of pregnancy, affecting 1%–2% of all reported pregnancies. Due to ethical constraints on human biopsies and the lack of suitable animal models, there has been little success in identifying functionally important genes in the pathogenesis of ectopic pregnancy. In the present study, we developed a random walk–based computational method named TM-rank to prioritize ectopic pregnancy–related genes based on text mining data and gene network information. Using a defined threshold value, we identified five top-ranked genes: VEGFA (vascular endothelial growth factor A), IL8 (interleukin 8), IL6 (interleukin 6), ESR1 (estrogen receptor 1) and EGFR (epidermal growth factor receptor). These genes are promising candidate genes that can serve as useful diagnostic biomarkers and therapeutic targets. Our approach represents a novel strategy for prioritizing disease susceptibility genes.

mRNA expression of VEGF and its receptors in fallopian tubes of women with ectopic pregnancies

BACKGROUND

Establishment of viable pregnancy requires embryo implantation and placentation. Ectopic pregnancy (EP) is a pregnancy complication which occurs when an embryo implants outside of the uterine cavity, most often in a fallopian tube. On the other hand, an important aspect of successful implantation is angiogenesis. Vascular endothelial growth factor (VEGF) is a potent angiogenic factor responsible for vascular development that acts through its receptors, VEGF receptor 1 (VEGFR1) and VEGFR2. This study aims to investigate mRNA expression of VEGF and its receptors in fallopian tubes of women who have EP compared with fallopian tubes of pseudo-pregnant women. We hypothesize that expression of VEGF and its receptors in human fallopian tubes may change during EP.

MATERIALS AND METHODS

This was a case-control study. The case group consisted of women who underwent salpingectomy because of EP. The control group consisted of women with normal fallopian tubes that underwent hysterectomy. Prior to tubal sampling, each control subject received an injection of human chorionic gonadotropin (hCG) to produce a state of pseudo-pregnancy. Fallopian tubes from both groups were procured. We investigated VEGF, VEGFR1 and VEGFR2 mRNA expressions in different sections of these tubes (infundibulum, ampulla and isthmus) by reverse transcription polymerase chain reaction (RT-PCR) and quantitative PCR (Q-PCR).

RESULTS

RT-PCR showed expressions of these genes in all sections of the fallopian tubes in both groups. Q-PCR analysis revealed that expressions of VEGF, VEGFR1 and VEGFR2 were lower in all sections of the fallopian tubes from the case group compared to the controls. Only VEGFR2 had higher expression in the ampulla of the case group.

CONCLUSION

Decreased expressions of VEGF, VEGFR1 and VEGFR2 in the EP group may have a role in the pathogenesis of embryo implantation in fallopian tubes.

Association between ultrasound findings and serum levels of vascular endothelial growth factor in ampullary pregnancy

OBJECTIVE

To assess the association between ultrasound images and serum concentrations of vascular endothelial growth factor (VEGF) in ampullary pregnancies.

DESIGN

Prospective study.

SETTING

University hospital.

PATIENT(S)

Fifty patients with ampullary pregnancy.

INTERVENTION(S)

Criteria for inclusion in the study were: singleton pregnancy from spontaneous conception; diagnosis of tubal pregnancy in the ampullary region; radical surgical treatment (salpingectomy); and measurement of serum VEGF, human chorionic gonadotropin, and progesterone on the day of surgery. An additional criterion was description of an ectopic mass by transvaginal ultrasound, as follows: [1] ectopic gestational sac containing an embryo with cardiac activity; and [2] tubal ring: a paraovarian formation similar to a gestational sac, not containing a viable embryo (an anechoic structure surrounded by a peripheral hyperechogenic halo); an empty ectopic gestational sac; a sac containing an embryo without cardiac activity; or a vitelline vesicle.

MAIN OUTCOME MEASURE(S)

Association between ultrasound images and serum concentrations of VEGF.

RESULT(S)

An association was found between ultrasonographic images and VEGF serum concentrations. Ectopic embryos with cardiac activity were associated with higher levels of serum VEGF.

CONCLUSION(S)

In ampullary pregnancy, higher serum levels of VEGF are associated with the finding of an embryo with cardiac activity on transvaginal ultrasound. Greater production of VEGF likely creates development conditions more conducive to ectopic embryos.

Molecular diagnostics and therapeutics for ectopic pregnancy

Ectopic pregnancies are a serious gynaecological emergency that can be fatal. As such, prompt diagnosis and safe timely treatment is essential. Here, we review the literature on the development of molecularly targeted diagnostics and therapeutics for ectopic pregnancy. A blood-based biomarker that accurately identifies an ectopic pregnancy could be used to offer early diagnostic certainty in cases where ultrasound cannot determine the location of the embryo ('a pregnancy of unknown location'). Molecules examined so far can be broadly grouped into biological themes of relevance to reproduction: (i) Fallopian tube (dys)function, (ii) embryo/trophoblast growth, (iii) corpus luteum function, (iv) inflammation, (v) uterine function and (vi) angiogenesis. While a sensitive and specific biomarker for ectopic pregnancy has yet to be identified, it is possible that improvements in platform technologies or a multi-modal biomarker approach may yield an accurate diagnostic biomarker test. Furthermore, with the advent of better imaging technology, the need for a blood-based biomarker test may be superseded by improvements in ultrasound or magnetic resonance imaging technology. There have been some recent preclinical studies describing molecularly targeted therapeutic approaches for ectopic pregnancy. Notably, bench-to-bedside studies have examined the use of combination gefitinib (orally available epidermal growth factor receptor inhibitor) and methotrexate. Preclinical studies suggest that combination gefitinib and methotrexate is highly effective in inducing placental cell death, and is significantly more effective than methotrexate alone. In early human trials, encouraging preliminary efficacy data have shown that combination gefitinib and methotrexate can rapidly resolve tubal ectopic pregnancies, and large extra-tubal ectopic pregnancies. If a large clinical randomized controlled trial confirms these findings, combination gefitinib and methotrexate could become a new medical treatment option for ectopic pregnancy.

Trophoblastic infiltration in tubal pregnancy evaluated by immunohistochemistry and correlation with variation of Beta-human chorionic gonadotropin

Objective. To evaluate trophoblastic cell proliferation and angiogenesis in tubal pregnancy assessed by immunohistochemical study and their correlation with an average variation of β-hCG in an interval of 48 hours before surgery. Methods. A prospective study was conducted on 18 patients with a diagnosis of tubal pregnancy. The patients were divided into two groups of ectopic pregnancy of which 11 showed rise of β-hCG levels and 7 patients showed declining β-hCG levels in an interval of 48 hours prior to surgery. Trophoblastic cell proliferation and angiogenesis were assessed by Ki-67 and VEGF, respectively. Trophoblastic cell proliferation was assessed by Ki-67 and was classified into three groups (grade I: less than 1/3 of stained nuclei, grade II: 1/3 to 2/3 of the stained nuclei, and grade III: more than 2/3 of the nuclei stained). The cases analyzed for VEGF were divided into three groups (grade I: less than 1/3 of the stained cytoplasm; grade II: 1/3 to 2/3 of the stained cytoplasm; grade III: more than 2/3 of the stained cytoplasm). Statistical analysis was performed using the chi-square, ANOVA, and Kruskal-Wallis tests. Results. The mean variation in the serum β-hCG levels in 48 hours in tubal pregnancy patients correlated with trophoblastic cell proliferation assessed by Ki-67 and showed a decline of 13.46% in grade I, a rise of 45.99% in grade II, and ascension of 36.68% in grade III (P = 0.030). The average variation in the serum β-hCG in 48 hours, where angiogenesis was evaluated by VEGF, showed a decline of 18.35% in grade I, a rise of 32.95% in grade II, and ascension of 37.55% in grade III (P = 0.047). Conclusions. Our observations showed a direct correlation of increased levels of serum β-hCG in 48h period prior to surgery with higher trophoblastic cell proliferation assessed by Ki-67 and angiogenesis assessed by VEGF in tubal pregnancy.

Maternal Serum Macrophage Inhibitory Cytokine-1 as a Biomarker for Ectopic Pregnancy in Women with a Pregnancy of Unknown Location

BACKGROUND

Ectopic pregnancy (EP) occurs in 1-2% of pregnancies, but is over-represented as a leading cause of maternal death in early pregnancy. It remains a challenge to diagnose early and accurately. Women often present in early pregnancy with a 'pregnancy of unknown location' (PUL) and the diagnosis and exclusion of EP is difficult due to a lack of reliable biomarkers. A serum biomarker able to clearly distinguish between EP and other pregnancy outcomes would greatly assist clinicians in diagnosing and safely managing PULs. This study evaluates the ability of maternal serum macrophage inhibitory cytokine-1 (MIC-1) levels to differentiate between EP and other pregnancy outcomes in women with a PUL.

METHODS

Sera were collected from 120 women with a PUL at first clinical presentation and assayed for MIC-1 by ELISA. Results were classified according to ultimate pregnancy outcome and the discriminatory ability of MIC-1 to diagnose EP was assessed.

RESULTS

Serum MIC-1 levels were lower in women with histologically confirmed (definite) EP (dEP) (median 552 ng/mL; interquartile range (IQR) 414-693 ng/mL) compared to women with definite viable intra-uterine pregnancies (dVIUPs) (722 ng/mL; IQR 412-1122 ng/mL), and higher when compared to women with definite non-viable intra-uterine pregnancies (dNVIUPs) (465 ng/mL; IQR 341-675 ng/mL). MIC-1 levels were significantly higher in women with dEP compared to women whose PULs resolved without medical intervention (srPUL) (401 ng/mL; IQR 315-475 ng/mL) (p<0.003). There were no women with an ectopic pregnancy where serum MIC-1>1000 ng/mL.

CONCLUSION

Serum MIC-1 levels in PUL were not able to categorically diagnose EP, however, MIC-1 could distinguish women with an EP that required medical intervention and those women whose PULs spontaneously resolved. A single serum MIC-1 measurement also excluded EP at levels above 1000 ng/mL. MIC-1 may play a role in the development of a combined assay of biomarkers for the diagnosis of EP.

Expressions of candidate molecules in the human fallopian tube and chorionic villi of tubal pregnancy exposed to levonorgestrel emergency contraception

BACKGROUND

Cases of ectopic pregnancy (EP) following levonorgestrel (LNG) emergency contraception (EC) failure were reported, however, the effects of LNG on tubal microenvironment or chorionic villi in EP have not yet been documented.

METHODS

Fifty-five women with tubal pregnancy were divided into two groups according to whether LNG-EC was administrated during the cycle of conception. The serum concentrations of beta-hCG, E2 and P were measured. The mRNA and protein expressions of estrogen and progesterone receptors, leukemia inhibitory factor, vascular endothelial growth factor, inducible nitric oxide synthase, and endocannabinoid receptor - CB1 in the ectopic implantation site and chorionic villi were examined.

RESULTS

Compared to those unexposed to LNG-EC, women with tubal pregnancy exposed to LNG-EC during the cycle of conception had no statistically significances in the serum concentrations of beta-hCG, E2 P, nor in the pathological types of tubal pregnancy or the expressions of ER-alpha, PR, LIF, VEGF, iNOS and CB1.

CONCLUSIONS

The expressions of candidate molecules in the fallopian tube and chorionic villi were not altered by exposure to LNG-EC. A routine therapy with no additional intervention might thus be applied to tubal pregnancy exposed to LNG-EC.

Comparison of the diagnostic values of circulating steroid hormones, VEGF-A, PIGF, and ADAM12 in women with ectopic pregnancy

Background

Several peripheral proteins that might be useful for detecting the presence of ectopic pregnancy (EP) have been evaluated, but none have been proven entirely useful in the clinic. We investigated the presence and the possible changes in circulating molecules that distinguish between normal intrauterine pregnancy (IUP) and tubal ectopic pregnancy.

Methods

Non-pregnant women during the menstrual cycle, women with IUP, and women with tubal EP after informed consent. Serum levels of 17β-estradiol (E2), progesterone (P4), testosterone (T), beta-human chorionic gonadotropin (β-hCG), vascular endothelial growth factor-A (VEGF-A), placental growth factor (PIGF), and a distintegrin and metalloprotease protein 12 (ADAM12) were analyzed. Receiver operating characteristic analysis was used to assess the diagnostic discrimination of EP and gestational age-matched IUP.

Results

E2, P4, PIGF, and ADAM12 levels increased and β-hCG decreased throughout IUP. E2 and VEGF-A levels were significantly different between women with tubal EP and IUP. However, using a serum β-hCG cut-off of less than 1000 mIU/mL, P4 was significantly lower in women with tubal EP compared to IUP. Although E2 was inversely correlated with VEGF-A in women in the early stages of IUP, E2 was not correlated with VEGF-A in women with EP prior to tubal surgery. There were no significant differences in either PIGF or ADAM12 alone between women with tubal EP or IUP. Although no significant correlations were seen between E2 and PIGF or P4 and ADAM12 in women in the early stages of IUP, E2 was positively correlated with PIGF and P4 was positively correlated with ADAM12 in women with EP prior to tubal surgery. Our studies defined associations but not causality.

Conclusions

Individual measurements of serum E2 or VEGF-A levels are strongly related to early pregnancy outcomes for women with IUP and EP, and pregnancy-associated E2 and VEGF-A levels provide diagnostic accuracy for the presence of tubal EP. This study demonstrates that correlation analysis of E2/VEGF-A and E2/PIGF serum levels may be able to distinguish a tubal EP from a normal IUP.

Biomarkers for ectopic pregnancy and pregnancy of unknown location

Early pregnancy failure is the most common complication of pregnancy, and 1% to 2% of all pregnancies will be ectopic. As one of the leading causes of maternal morbidity and mortality, diagnosing ectopic pregnancy and determining the fate of a pregnancy of unknown location are of great clinical concern. Several serum and plasma biomarkers for ectopic pregnancy have been investigated independently and in combination. The following is a review of the state of biomarker discovery and development for ectopic pregnancy and pregnancy of unknown location.

The vascular endothelial growth factor (VEGF) +405 G/C polymorphism and its relationship with recurrent implantation failure in women in an IVF programme with ICSI

PURPOSE

Successful embryo implantation depends on trophoblast proliferation, migration and, lastly, invasion of the endometrium (to anchor the trophoblast to the uterus). This invasion is mediated by locally produced soluble factors. Of these, vascular endothelial growth factor (VEGF) is the best characterized regulator of angiogenesis. Here, we investigate the association between the VEGF + 405 C/G genotype and the recurrence of embryo implantation failure in women undergoing in vitro fertilization (IVF) program with intracytoplasmic sperm injection (ICSI).

METHODS

Forty women with recurrent implantation failure defined by absence of pregnancy after transfer of more than 10 embryos and 131 women control, with at least one live birth after the transfer of fewer than 10 embryos were included. Genomic DNA was analysed with an allele-specific polymerase chain reaction and a Chi-2 test was used to compare the respective VEGF + 405 C/G genotype frequencies in cases and controls.

RESULTS

The frequency of the VEGF +405C/C genotype was higher in women with recurrent implantation failure after ICSI-embryo transfer than in controls (17.5 % and 5.3 %, respectively, p = 0.01).

CONCLUSION

The VEGF +405 G/C polymorphism may influence embryo implantation and VEGF + 405 C/C genotype may predispose to recurrent implantation failure after ICSI-ET.

Increased endometrial placenta growth factor (PLGF) gene expression in women with successful implantation

OBJECTIVE

To analyze the vascularization of the endometrium via hysteroscopy and to assess its correlation with angiogenic factor gene expression and embryo implantation rate.

DESIGN

Cross-sectional study.

SETTING

Public university hospital.

PATIENT(S)

Patients undergoing hysteroscopy for supposed infertility.

INTERVENTION(S)

Endometrial quality assessment according to Sakumoto-Masamoto, performed in the early secretory phase of the cycle. Collection of an endometrial tissue biopsy.

MAIN OUTCOME MEASURE(S)

RNA extraction, reverse transcription, and determination of gene expression of angiogenesis- and implantation-relevant factors using quantitative polymerase chain reaction. Retrieval of pregnancy information from the medical records.

RESULT(S)

Good quantity/quality RNA with infertility history was obtained from 63 participating women. Those with a "good" endometrium and subsequent pregnancy showed increased gene expression for placenta growth factor when compared with patients with a "bad" endometrium and who did not succeed with pregnancy to date. Nonpregnant women with a "good" endometrium presented an intermediate result. No significant differences were observed for several other genes tested, but trends in the same direction were observed.

CONCLUSION(S)

This study demonstrates for the first time that endometrial PLGF expression corresponds to the hysteroscopic appearance of the endometrium, and therefore has potential as a clinically relevant prognosticator for infertility treatment success.

Development of a multiple marker test for ectopic pregnancy

OBJECTIVE

Many serum markers have been proposed to aid in the identification of an ectopic pregnancy, but few have been validated. Most studies have been limited by sample size and design. The goal of this study was to assess putative markers to identify which can be optimally combined.

METHODS

We conducted a case-control study using sera from 100 patients with ectopic pregnancy and 100 patients with intrauterine pregnancy who presented to three urban academic centers between September 2000 and April 2009 with first-trimester pain or bleeding. Samples were analyzed for 12 promising biomarkers. Classification tree analysis was used to examine markers simultaneously with the goal of optimizing the accuracy of ectopic pregnancy diagnosis, and validation was performed using bootstrapping.

RESULTS

Six of the 12 markers were differentially expressed between those with ectopic pregnancy and intrauterine pregnancy (P<.001) with fair diagnostic properties (area under the curve greater than 0.6) when examined individually (inhibin A, progesterone, activin A, vascular endothelial growth factor [VEGF], pregnancy-specific β-1-glycoprotein, and pregnancy-associated plasma protein-A). Six additional markers were found to have limited value. Using a two-step diagnostic algorithm with four markers (progesterone, VEGF, inhibin A, activin A), we diagnosed 42% of the sample with perfect specificity and 98% (93-100%) sensitivity. Overall, a single ectopic pregnancy was misclassified, achieving 99% (96-100%) accuracy.

CONCLUSION

Evaluating a large number of biomarkers simultaneously demonstrates that most of the putative markers of ectopic pregnancy are not useful. However, a select few can distinguish ectopic pregnancy from intrauterine pregnancy with superior accuracy as part of a multiple marker test.

CLINICAL TRIAL REGISTRATION

: ClinicalTrials.gov, www.clinicaltrials.gov, NCT00194168.

Current knowledge of the aetiology of human tubal ectopic pregnancy

BACKGROUND An ectopic pregnancy is a pregnancy which occurs outside of the uterine cavity, and over 98% implant in the Fallopian tube. Tubal ectopic pregnancy remains the most common cause of maternal mortality in the first trimester of pregnancy. The epidemiological risk factors for tubal ectopic pregnancy are well established and include: tubal damage as a result of surgery or infection (particularly Chlamydia trachomatis), smoking and in vitro fertilization. This review appraises the data to date researching the aetiology of tubal ectopic pregnancy. METHODS Scientific literature was searched for studies investigating the underlying aetiology of tubal ectopic pregnancy. RESULTS Existing data addressing the underlying cause of tubal ectopic pregnancy are mostly descriptive. There are currently few good animal models of tubal ectopic pregnancy. There are limited data explaining the link between risk factors and tubal implantation. CONCLUSIONS Current evidence supports the hypothesis that tubal ectopic pregnancy is caused by a combination of retention of the embryo within the Fallopian tube due to impaired embryo-tubal transport and alterations in the tubal environment allowing early implantation to occur. Future studies are needed that address the functional consequences of infection and smoking on Fallopian tube physiology. A greater understanding of the aetiology of tubal ectopic pregnancy is critical for the development of improved preventative measures, the advancement of diagnostic screening methods and the development of novel treatments.

Association study of vascular endothelial growth factor and polymorphisms of its gene with ectopic pregnancy

PROBLEM

In ectopic pregnancy, increased levels of vascular endothelial growth factor are present. The aims of this study were to determine the association between -634C/G, -460T/C, and +936C/T vascular endothelial growth factor (VEGF) polymorphisms and ectopic pregnancy, and to determine whether serum levels of VEGF were affected by genetic factors.

METHOD

of study This is a case-control study wherein 74 women with a history of ectopic pregnancy in a tertiary care center were compared to 134 post-menopausal controls with two pregnancies and no ectopic pregnancy for the genotyping of VEGF polymorphisms. For 35 patients with the diagnosis of ectopic pregnancy, serum concentrations of VEGF were obtained before the treatment. Genotyping of VEGF (-634C/G, -460T/C, and +936C/T) polymorphisms was performed by PCR, followed by endonuclease digestion. ELISA was performed to evaluate the VEGF serum levels.

RESULTS

The -634C/G, -460T/C, and +936C/T VEGF polymorphisms were not associated with ectopic pregnancy (P = 0.170, P = 0.285, and P = 0.700, respectively). The serum levels of VEGF were not associated with the genotype of -634C/G, -460T/C, and +936C/T VEGF polymorphisms (P = 0.702; P = 0.347, and P = 0.256, respectively).

CONCLUSION

There was no association between ectopic pregnancy and -634C/G, -460T/C, and +936C/T VEGF polymorphisms. There was no correlation between VEGF genotype and the expression of VEGF in blood samples.

Serum biomarkers of tubal ectopic pregnancy: current candidates and future possibilities

Ectopic pregnancy remains a considerable cause of maternal morbidity and mortality worldwide. Currently, it is diagnosed using a combination of transvaginal ultrasound and serial serum beta-human chorionic gonadotrophin levels. Diagnosis is often delayed and these tests are time-consuming and costly, both psychologically to the patient and financially to health services. The development of a biomarker that can differentiate a tubal ectopic from an intrauterine implantation is therefore important. In the pre-genomic era, a one-by-one scientific approach has revealed over 20 candidate biomarkers that could be used as a test to diagnose ectopic pregnancy although at present their clinical utility is very limited. These biomarkers cluster into themes: markers of abnormal embryo/trophoblast growth, markers of abnormal corpus luteum function, markers of a growing pregnancy in the Fallopian tube, markers of inflammation and peritoneal irritation, and uterine markers of normal implantation. It is likely that this thematic approach will facilitate the identification of newer biomarkers using microarray technology and inform the development of investigative paradigms using multiple markers at the time of presentation.

Ectopic pregnancy: diagnosis and management

The incidence of ectopic pregnancies is increasing, which may be related to better diagnostic tools as well as the increasing use of assisted reproductive technologies. However, the signs and symptoms of ectopic pregnancy can be similar to other complications of early pregnancy such as miscarriage. Diagnosis often requires serial human chorionic gonadotropin levels along with ultrasound and, in some cases, dilation and curettage. Once a diagnosis has been made, treatment options include medical therapy with methotrexate and surgery, which can often be performed via the laparoscope. Fertility rates after therapy are similar for both medically and surgically treated patients.

Serum markers in the diagnosis of tubal pregnancy

The introduction of highly sensitive methods, such as transvaginal sonography and measurement of serum b-human chorionic gonadotropin, has dramatically improved ectopic pregnancy diagnosis in recent years. Early diagnosis is the key to successful and conservative management of women with ectopic pregnancy; however, approximately 50 percent of such women are initially misdiagnosed, resulting in significant morbidity and mortality. In order to improve diagnosis, several serum markers are being investigated including progesterone, CA 125, pregnancy-associated plasma protein-A, vascular endothelial growth factor, and maternal creatine kinase. Measurement of serum vascular endothelial growth factor, alone or together with other markers, could be a promising method for earlier and more accurate differential diagnosis. However, the clinical applicability of these findings remains to be evaluated in larger prospective studies.

Predicting Outcomes in Pregnancies of Unknown Location

A pregnancy of unknown location (PUL) is a descriptive term used to classify a woman when she has a positive pregnancy test but no intra- or extra-uterine pregnancy is visualized on transvaginal sonography. Expectant management has been shown to be safe for the majority of women with a PUL. Serum progesterone and human chorionic gonadotrophin levels as well as mathematical models play a role in predicting the final outcomes of PULs, which include intrauterine pregnancy, failing PUL and ectopic pregnancy. Other possible predictors of outcome have been studied, but currently no factor has been identified that combines accuracy with reproducibility and simplicity. This article discusses the various aspects of the management of women with PULs. Future work should be aimed at prospectively testing current models in order to predict the outcome of a PUL and minimizing follow-up.

Quality of reporting of test accuracy studies in reproductive medicine: impact of the Standards for Reporting of Diagnostic Accuracy (STARD) initiative

OBJECTIVE

To evaluate the extent to which test accuracy studies published in two leading reproductive medicine journals in the years 1999 and 2004 adhered to the Standards for Reporting of Diagnostic Accuracy (STARD) initiative parameters, and to explore whether the introduction of the STARD statement has led to an improved quality of reporting.

DESIGN

Structured literature search. Articles that reported on the diagnostic performance of a test in comparison with a reference standard were eligible for inclusion. For each article we scored how well the 25 items of the STARD checklist were reported. These items deal with the study question, study participants, study design, test methods, reference standard, statistical methods, reporting of results, and conclusions. We calculated the total number of reported STARD items per article, summary scores for each STARD item, and the average number of reported STARD items per publication year.

SETTING

Not applicable.

PATIENT(S)

Not applicable.

INTERVENTION(S)

Not applicable.

MAIN OUTCOME MEASURE(S)

Quality of reporting.

RESULT(S)

We found 24 studies reporting on test accuracy in reproductive medicine in 1999 and 27 studies in 2004. The mean number of reported STARD items for articles published in 1999 was 12.1 +/- 3.3 (range 6.5-20) and 12.4 +/- 3.2 (range 7-17.5) in 2004, after publication of the STARD statement. Overall, less than half of the studies reported adequately on 50% or more of the STARD items. The reporting of individual items showed a wide variation. There was no significant improvement in mean number of reported items for the articles published after the introduction of the STARD statement.

CONCLUSION(S)

Authors of test accuracy studies in the two leading fertility journals poorly report the design, conduct, methodology, and statistical analysis of their study. Strict adherence to the STARD guidelines should be encouraged.

Presence of Cell-Free Fetal DNA in Plasma of Women with Ectopic Pregnancies,

Background: The quantity of cell-free fetal DNA in the plasma of pregnant women changes during pregnancy and seems to be different in normal and pathologic pregnancies. We investigated the possible diagnostic applications of the detection and measurement of cell-free fetal DNA by comparing quantities found in women with ectopic (EP) or intrauterine (IUP) pregnancies.

Methods: We collected blood samples from 58 women who had positive pregnancy tests and specific complaints and sonographic findings suggestive of EP and from 45 women with confirmed IUP. We performed quantitative real-time PCR analysis of the sex-determining region Y (SRY) gene to detect and measure the amount of cell-free fetal DNA. The diagnosis of EP was confirmed by histologic examination.

Results: SRY was detected in 15 EP and 14 IUP cases. The mean (SD) amount of cell-free fetal DNA was significantly higher (P &lt;0.005) in women with EP [565 (136) genome-equivalents (GE)/mL] than in women with IUP [72 (19) GE/mL] at the same gestational age.

Conclusions: Our results confirm that cell-free fetal DNA is present in plasma of women with EP. The finding of higher amounts of cell-free fetal DNA in EP cases than in IUP cases suggests that this method might be useful for early diagnosis of EP.

Hypoxia regulates vascular endothelial growth factor and soluble fms-like tyrosine kinase-1 secretion by human oviductal epithelial cells and stromal fibroblasts

OBJECTIVE

To evaluate the effect of hypoxia on the production of vascular endothelial growth factor (VEGF) and soluble fms-like tyrosine kinase-1 (sFlt-1) in the human fallopian tube.

DESIGN

The secretion of VEGF and sFlt-1 by cultured oviductal epithelial cells (OECs) and oviductal stromal fibroblasts (OSFs) in response to hypoxia was investigated.

SETTING

Research laboratory at a medical school.

PATIENT(S)

Normal oviducts obtained from seven premenopausal patients were used.

INTERVENTION(S)

Oviductal epithelial cells and OSFs were incubated under normoxic (20% O2) or hypoxic (2% O2) conditions.

MAIN OUTCOME MEASURE(S)

The concentrations of VEGF and sFlt-1 in the culture media of OECs and OSFs were measured by enzyme-linked immunosorbent assays.

RESULT(S)

The secretion of both VEGF and sFlt-1 was detected in cultured OECs and OSFs and was found to have been stimulated under hypoxic conditions in these cells.

CONCLUSION(S)

The present findings suggest that hypoxia in the local environment may stimulate oviductal vascular permeability by inducing the production of VEGF by oviductal cells. Simultaneous up-regulation of sFlt-1 secretion by these cells under hypoxic conditions may prevent excessive up-regulation of vascular permeability. The modulation of the bias of VEGF and sFlt-1 in the fallopian tubes may contribute to the normal and pathological processes of oviductal fluid secretion by regulating oviductal vascular permeability during the menstrual cycle.

Suspected Ectopic Pregnancy

Women who present with pain and bleeding in the first trimester are at risk for ectopic pregnancy, a life-threatening condition. Conditions that predispose a woman to ectopic pregnancy are damaged fallopian tubes from prior tubal surgery or previous pelvic infection, smoking, and conception using assisted reproduction. Many women without risk factors can develop an ectopic pregnancy. A diagnostic algorithm that includes the use of transvaginal ultrasonography, human chorionic gonadotropin (hCG) concentrations, and, sometimes, uterine curettage can definitively diagnose women at risk in a timely manner. The absence of an intrauterine pregnancy above an established cut point of hCG is consistent with an abnormal pregnancy but does not distinguish a miscarriage from an ectopic pregnancy. When the initial hCG value is low, serial hCG values can be used to determine whether a gestation is potentially viable or spontaneously resolving. The minimal rise in hCG for a viable pregnancy is 53% in 2 days. The minimal decline of a spontaneous abortion is 21-35% in 2 days, depending on the initial level. A rise or fall in serial hCG values that is slower than this is suggestive of an ectopic pregnancy. Women diagnosed with an unruptured ectopic pregnancy are potential candidates for medical management with methotrexate. Intramuscular injection with methotrexate can be used to safely treat an ectopic pregnancy with success rates, tubal patency rates, and future fertility that are similar to those obtained with conservative surgery. Success rates using methotrexate are inversely rated to baseline hCG values and are higher using "multidose" compared with "single-dose" regimens. Surgical treatment may be conservative or definitive and should be attempted in most cases via laparoscopy.

The value of a single combined measurement of VEGF, glycodelin, progesterone, PAPP-A, HPL and LIF for differentiating between ectopic and abnormal intrauterine pregnancy

BACKGROUND

To evaluate whether serum concentrations of the non-placental markers vascular endothelial growth factor (VEGF), glycodelin (GLY) and progesterone (P) and the novel placental markers pregnancy-associated plasmaprotein A (PAPP-A), human placental lactogen (HPL) and leukaemia inhibiting factor (LIF) differ in ectopic pregnancy (EP) when compared with abnormal intrauterine pregnancy (aIUP).

METHODS

A prospective clinical study was conducted at the University Hospital of Larissa, Greece. The study included 50 patients admitted with failed pregnancy and suspected ectopic pregnancy that were treated with curettage or laparoscopy and classified as histologically confirmed EPs (n = 27) or histologically confirmed aIUPs (n = 21) (mean gestational age of 7.15 and 7.3 weeks, respectively). Two suspected EPs proved to be normal IUPs and were excluded. VEGF, GLY, P, beta-HCG, PAPP-A, HPL and LIF were measured by enxyme-linked immunosorbent assay (ELISA) methods in a single pre-operative blood sample.

RESULTS

The median VEGF concentration was 227.2 pg/ml in the EP group versus 107.2 pg/ml in the aIUP group (P < 0.001), with a suggested threshold value of 174 pg/ml for their differential diagnosis. LIF, P, PAPP-A, HPL and GLY serum measurements did not differ significantly between EP and aIUP.

CONCLUSION

VEGF serum levels might be a useful marker in differentiating between EPs and aIUPs.

Maternal serum vascular endothelial growth factor levels in early ectopic and intrauterine pregnancies after in vitro fertilization treatment

OBJECTIVE

To determine whether serum levels of vascular endothelial growth factor (VEGF) 11 days after a day-3 embryo transfer were predictive of outcome, in women with normal intrauterine pregnancy (IUP), first-trimester miscarriage (SAB), biochemical (BC), and ectopic pregnancy (EP) after IVF therapy.

DESIGN

Retrospective analysis.

SETTING

University hospital IVF unit.

PATIENT(S)

One hundred eight women who underwent IVF therapy and who were subsequently diagnosed with EP, BC, SAB, or a normal IUP (27 in each category).

INTERVENTION(S)

Serum samples were obtained at 11 days after a day-3 embryo transfer.

MAIN OUTCOME MEASURE(S)

Serum concentrations of VEGF, P, and beta-hCG.

RESULT(S)

Serum concentrations of VEGF were similar in women with BC and EP and higher than in women with normal IUP and SAB (571.8 +/- 61.8, 604.4 +/- 73.4 vs. 448.9 +/- 39.9, 461.8 +/- 39.2 pg/mL, respectively). Also, serum beta-hCG and P levels were significantly higher in women with a normal IUP and SAB. Using a cutoff concentration of >700 pg/mL for VEGF, an EP could be distinguished from an IUP (normal and SAB), with a positive predictive value of 64% and a negative predictive value of 71%.

CONCLUSION(S)

Elevated maternal serum levels of VEGF, as early as 11 days after embryo transfer, are associated with ectopic pregnancies after IVF.

Increased messenger RNA expression of vascular endothelial growth factor and its receptors in the implantation site of the human oviduct with ectopic gestation

OBJECTIVE

To compare the mRNA expression of vascular endothelial growth factor (VEGF) and its receptors (KDR and flt-1) in the implantation and nonimplantation sites of the human oviduct with ectopic gestation.

DESIGN

Prospective observational study.

SETTING

University-based Obstetrics and Gynecology Department.

PATIENT(S)

Ten women undergoing laparoscopic salpingectomy for tubal pregnancy.

INTERVENTION(S)

The mucosal layer was isolated from the implantation and nonimplantation sites of the oviduct tissue with ectopic gestation. Semiquantitative reverse transcriptase-polymerase chain reaction was performed.

MAIN OUTCOME MEASURE(S)

The differences in the mRNA expression of VEGF and its receptors between the implantation and nonimplantation sites of the oviduct tissue.

RESULT(S)

The mRNA expression of VEGF and its receptors, both KDR and flt-1, was significantly higher in the implantation site of the human oviduct with ectopic gestation compared with the nonimplantation site.

CONCLUSION(S)

The results suggest that VEGF may be the angiogenic factor responsible for the implantation and placentation of an ectopic pregnancy in the oviduct.

Novel placental and nonplacental serum markers in ectopic versus normal intrauterine pregnancy

OBJECTIVE

To evaluate whether the serum concentrations of novel placental markers and nonplacental markers differ in ectopic pregnancy when compared with normal intrauterine pregnancy.

DESIGN

Prospective clinical study.

SETTING

University hospital.

PATIENT(S)

Patients with confirmed ectopic pregnancy (EP) and control population with normal intrauterine pregnancy (IUP).

INTERVENTION(S)

Laparoscopy.

MAIN OUTCOME MEASURE(S)

Serum concentrations of placental markers: pregnancy-associated plasma protein A (PAPP-A), pregnancy-specific beta(1)-glycoprotein (SP1), human placental lactogen (HPL), and HCG; and nonplacental markers: glycodelin, vascular endothelial growth factor (VEGF), and P.

RESULT(S)

The multiples of median of all markers (except VEGF) were decreased in EP when compared with the control group. Conversely, the serum values of VEGF were significantly increased in EP. VEGF showed a negative correlation with HCG and SP1, but not with PAPP-A, P, or the nonplacental markers. HCG, PAPP-A, SP1, and HPL strongly correlated with each other. But, in contrast to the above, P only correlated with HCG and, in contrast to the controls, with glycodelin. The combination of three independent markers in the formula VEGF/(PAPP-A x P) was found to be largely superior to the measure of any single marker.

CONCLUSION(S)

The "triple marker analysis" [VEGF/(PAPP-A x P] allows a clear discrimination between normal IUP and EP.

Human embryo implantation: current knowledge and clinical implications in assisted reproductive technology

A pregnancy rate of approximately 15% per cycle renders the process of human reproduction inefficient. The cycle-dependent expression of molecules involved in the embryo-endometrial dialogue has lead to the identification of a 'window of implantation'. This is the unique temporal and spatial expression of factors that allows the embryo to implant (via signalling, appositioning, attachment and invasion) in a specific time frame of 48 h, 7-10 days after ovulation. Integrin molecules, L-selectin ligands, mucin-1, heparin-binding epidermal growth factor and pinopodes are involved in appositioning and attachment. The embryo produces cytokines and growth factors [interleukins, prostaglandins, vascular endothelial growth factor (VEGF)] and receptors for endometrial signals (leukaemia inhibitory factor receptor, colony stimulating factor receptor, insulin-like growth factors and heparin binding epidermal growth factor receptor). The immune system plays an important role. Immunomodulatory factors such as glycodelin, inhibin and interleukin prevent a graft-versus-host reaction. Angiogenesis controlled by VEGF and prostaglandins is needed for formation of a receptive endometrium and a placenta. Identification of these factors has led to their use as markers of implantation that may identify defects causing subfertility. An ideal marker of implantation is sensitive and specific, and easy to obtain without disturbing implantation. Glycodelin and leukaemia inhibitory factor (serum) and integrins and pinopodes (biopsies) are promising candidates.

Vascular endothelial growth factor serum levels are elevated in patients with hereditary hemorrhagic telangiectasia

BACKGROUND

Hereditary hemorrhagic telangiectasia (HHT) is a genetic angiodysplasia affecting multiple organs. Two genes involved in the transduction of TGF-beta signalling are responsible for HHT. An additional role for vascular endothelial growth factor (VEGF) has been proposed. Serum VEGF, which has been evaluated in several diseases characterized by aberrant angiogenesis, has never been measured in patients with HHT.

AIMS

To evaluate VEGF serum levels in HHT patients as compared to normal subjects.

MATERIALS AND METHODS

32 HHT patients (age 47.7 +/- 16.7 years) and a control group of 37 healthy subjects (age 48.2 +/- 15.5 years) were entered in the study. Each patient underwent serum VEGF dosage using a commercial ELISA specific for the human molecule.

RESULTS

The serum level of VEGF in HHT patients was 196.3 +/- 103.2 pg/ml, while it was 152.0 +/- 84.1 pg/ml in the control group. Statistical analysis showed that serum VEGF was significantly higher in HHT patients than in the controls (p < 0.031).

CONCLUSIONS

According to a study performed in a murine model, persistence of the activation phase of angiogenesis might be responsible for an increased production of several angiogenic factors, in particular VEGF, in HHT. Our work is the first to suggest an increased expression of VEGF in the serum of subjects with HHT in agreement with the stimulation of VEGF synthesis proposed in the murine model.

Ectopic pregnancy: an update

This review addresses recent publications that investigate etiology, epidemiology and different modalities in diagnosis and therapy for ectopic pregnancy. A significant proportion of recent work has focused in the development of new diagnostic tools to aid in the early detection of ectopic pregnancy. Diagnostic modalities have included systemic and local markers, vascular endothelial growth factor, vascular cell adhesion molecule-1, urokinase plasminogen activator receptor, cervical fetal fibronectin, and hormonal level determinations. In addition, magnetic resonance imaging, ultrasonography, color flow mapping and endometrial thickness have been evaluated. New studies have investigated controversial issues related to the cost of the medical versus surgical treatment and the use of different medications and techniques for the management of ectopic pregnancy. Most important of all, several lines of investigation have addressed the use of human chorionic gonadotropin, algorithms, and scoring systems as prognostic indicators of successful therapy and to determine the risk of complications. The management of cervical, interstitial and heterotopic pregnancy is evaluated in this review and a summary of recent proposed diagnostic tools and concepts in management is also presented.

Evidence-based management of ectopic pregnancy

In selected cases, medical treatment of ectopic pregnancy with methotrexate is as effective as laparoscopic surgery. However, medical treatment might have a more negative impact on the health-related quality of life than surgical treatment. This is partly because of the long resolution time after medical treatment. New evidence suggests that combining methotrexate and mifepristone can shorten this resolution time.