Treatment of hydrosalpinx in relation to IVF outcome: a systematic review and meta-analysis

The outcome of embryo transfer after three different procedures for laparoscopic correction of hydrosalpinx

OBJECTIVE

To compare the effect of three different surgical approaches: simple terminal salpingostomy, bilateral proximal tubal ligation plus terminal salpingostomy, and bilateral salpingectomy.

METHODS

A retrospective analysis was conducted on the clinical data of 292 patients who underwent laparoscopic surgery for hydrosalpinx and embryo transfer within 2 years postoperatively from January 2018 to August 2021. The patients were divided into three groups: Group A (68 cases) underwent simple terminal salpingostomy, Group B (199 cases) underwent ligation plus terminal salpingostomy, and Group C (25 cases) underwent bilateral salpingectomy.

RESULTS

Age, body mass index, surgical time, intraoperative bleeding, length of hospital stay, and infertility type showed no significant differences among the different surgical groups (P > 0.05), except for the age 30-39 group, which showed statistically significant differences in surgical time (P < 0.001) and length of hospital stay (P < 0.001); the age 40 or above group showed statistically significant differences in intraoperative bleeding (P = 0.008). A total of 336 oocyte retrievals and 451 embryo transfers were successfully performed in the 292 patients within 2 years postoperatively.

CONCLUSION

The choice of surgical approach for hydrosalpinx does not affect pregnancy rates after embryo transfer within the same age group.

Comparison of salpingectomy and tubal occlusion for hydrosalpinx in in-vitro fertilization outcome

The occurrence of hydrosalpinx can reduce the success rate of assisted reproductive technology. The laparoscopic salpingectomy and tubal occlusion have been shown to improve in-vitro fertilization (IVF) outcomes in this disease. The primary goal of this review was to assess and compare the IVF outcome following salpingectomy or tubal occlusion in the published literature. The authors included studies with at least one of the following outcomes: days of controlled ovarian hyperstimulation, retrieved oocyte number, fertilization rates, clinical pregnancy rate, miscarriage rate, or ectopic pregnancy rate. In conclusion, proximal tubal occlusion outperforms salpingectomy in terms of fertilization rate while offering no evident advantages in terms of days of controlled ovarian hyperstimulation, retrieved oocytes number, IVF results, or problems in treating hydrosalpinx patients prior to IVF. These data may help clinicians choose the best therapy for patients with hydrosalpinx prior to IVF.

Comparisons of different treatment outcomes in IVF/ET patients with hydrosalpinx: a retrospective study

AIMS

To explore suggestions for clinicians on the most effective treatment for hydrosalpinx undergoing IVF-ET.

MATERIALS AND METHODS

We reviewed 936 women with hydrosalpinx and 6715 tubal infertile women without hydrosalpinx who underwent IVF/ICSI between January 2014 and August 2019 in our center. Hydrosalpinx patients received different treatments including laparoscopic surgery (only salpingectomy and proximal tubal occlusion/ligation were included), ultrasonic-guided aspiration and hysteroscopic tubal occlusion. Outcomes were analyzed by One-way ANOVA, Chi-Square test and logistic regression.

RESULTS

The live birth rate (LBR) of laparoscopic surgery was significantly higher compared with hydrosalpinx aspiration (48.3% vs 39.6%, p = .024). The cumulative live birth rate (CLBR) of subsequent laparoscopic surgery was significantly higher compared with subsequent hysteroscopic occlusion (65.1% vs 34.1%, p = .001) and no subsequent treatment (65.1% vs 44.9%, p  <  .005). Subsequent laparoscopic surgery significantly improved the CLBR of hydrosalpinx patients who received ultrasonic-guided aspiration and didn't get clinical pregnancy in fresh cycles (Odds Ratio (OR) =1.875; 95%CI = 1.041-3.378, p = .036).

CONCLUSIONS

Laparoscopic surgery leads to significantly higher LBR than ultrasonic-guided aspiration and significantly higher CLBR than hysteroscopic occlusion and no treatment.

Ovarian Follicular Response Is Altered by Salpingectomy in Assisted Reproductive Technology: A Pre- and Postoperative Case-Control Study

Objectives: The goal of this study was to assess the effect of unilateral salpingectomy on the number of mature follicles in the ipsilateral ovary during an assisted reproductive technology (ART) stimulation cycle, as compared to the contralateral ovary. Methods: This was a retrospective, single-center, case-control cohort study conducted from 2017 to 2022. Patients from 18 to 43 years old who underwent at least one ART cycle before and after a unilateral salpingectomy were included. The number of recruited follicles, including mature (≥16 mm) and intermediate follicles (13-15.5 mm), on the salpingectomy side (case) were compared to those present on the contralateral ovary (control) during an ART attempt. To take into account the inter-ovarian variability, the comparison was performed on two ART cycles, performed before then after the salpingectomy. Results: Overall, 24 patients were included in our study. While the number of mature follicles was similar in both ovaries before surgery, the mean number of mature follicles was significantly reduced after salpingectomy in the operated side, as compared to the control side, being, respectively 3.00 vs. 5.08 (p = 0.048). There was no significant difference between the intermediate and total recruited follicles. Conclusions: Our study suggests that salpingectomy may impact the follicle recruitment on the ipsilateral side by altering the vascularization during mesosalpinx coagulation. Gynecologists should be mindful of this concept and accurately set surgical indications. Beyond the indication, this emphasizes the critical role of having infertility surgeons sensitive to fertility preservation for optimal management of ART patients. Further studies with larger patient populations are required to confirm these results.

Tubal Pathologies and Fertility Outcomes: A Review

Anomalies of the fallopian tubes represent one of the most significant elements that might contribute to reproductive issues. They can be inherited or acquired; they are among the most important problems of the profession. Although there is much discussion regarding which therapies for each tubal disease are the most effective and result in the best long-term reproductive outcomes. During the evaluation of an infertile couple, certain anomalies of the fallopian tubes are frequently discovered. These abnormalities were thought, for a long time, to not have an influence on fertility; however, in recent years, researchers have discovered that they seem to play a crucial role in fertility problems. Couples in industrialized countries are postponing childbearing, which raises the risk of women developing tubal diseases before they are ready to become pregnant. These disorders may have a negative impact on a woman's ability to get pregnant. The goals of this study are to conduct research to gain a deeper understanding of the recent advancements that have been made in the field of tubal diseases and to carry out an evaluation of the medical conducts that have the best fertility outcomes. We searched both Medline and PubMed, paying special attention to the most relevant articles that have been added to either database over the course of the last six years.

The influence of timing of oocytes retrieval and embryo transfer on the IVF-ET outcomes in patients having bilateral salpingectomy due to bilateral hydrosalpinx

Objective

The objective of the study was to investigate whether the sequence of oocyte retrieval and salpingectomy for hydrosalpinx affects pregnancy outcomes of in vitro fertilization and embryo transfer (IVF-ET) patients.

Study Design

There were 1,610 bilateral hydrosalpinx patients who underwent laparoscopy salpingectomy and IVF-ET/intracytoplasmic sperm injection (ICSI) from January 2009 to December 2018. They were divided into two groups: oocyte retrieval first group: 235 accepted oocyte retrieval before salpingectomy; operation first group: 1,375 accepted oocyte retrieval after salpingectomy. The basic information and pregnancy outcomes of the two groups were compared. The pregnancy outcomes and influencing factors were analyzed among patients at different starting times of frozen-thawed embryo transfer (FET) or oocyte retrieval after the salpingectomy.

Results

Patients in the oocyte retrieval first group had higher levels of basal follicle stimulating hormone and lower anti-Mullerian hormone levels (P < 0.05). There were no cases of pelvic infection or oocyte and embryo contamination after oocyte retrieval in the oocyte retrieval first group. In the frozen cycle, the clinical pregnancy and miscarriage rates of the oocyte retrieval first group were lower than those in the operation first group (P < 0.05), while the live birth rate was not significantly different (P > 0.05). The live birth rates of patients ≥35 years old in the operation first group and the oocyte retrieval first group were not significantly different (29.3% vs. 23.3%, P = 0.240). After adjusting for age and antral follicle count (AFC), oocyte retrieval 4-6 and 7-12 months after the operation had higher accumulated pregnancy rates [OR 1.439 (1.045-1.982), P = 0.026; OR 1.509 (1.055-2.158), P = 0.024] and higher accumulated live birth rates [OR 1.419 (1.018-1.977), P = 0.039; OR 1.544 (1.068-2.230), P = 0.021]. No significant difference was observed in the pregnancy outcomes of frozen embryo transfer at different times after salpingectomy (P > 0.05).

Conclusion

No contamination of the embryo or infection was observed in patients who underwent oocyte retrieval before the operation. The interval between the operation and frozen embryo transfer did not affect the pregnancy outcomes. After adjusting for age and AFC, patients who underwent oocyte retrieval 4-6 and 7-12 months after the operation had higher accumulated pregnancy rates and live birth rates.

Prior salpingectomy impairs the retrieved oocyte number in in vitro fertilization cycles of women under 35 years old without optimal ovarian reserve

STUDY OBJECTIVE

The impairment of the ovarian response in in vitro fertilization (IVF) cycles after salpingectomy remains contentious. Therefore, we investigated whether a history of salpingectomy affects the number of oocytes retrieved in women undergoing IVF in comparison with the number in women without underlying tubal disease.

DESIGN

Case-control study (Canadian Task Force Classification II-2).

SETTING

A tertiary hospital-affiliated fertility center.

PATIENTS

Fifty-four women aged <35 years with a history of salpingectomy and 59 age-matched women without tubal disease.

INTERVENTIONS

Gonadotropin-releasing hormone antagonist protocol for controlled ovarian stimulation and transvaginal oocyte retrieval.

MEASUREMENTS AND MAIN RESULTS

The antral follicle count (AFC), anti-Müllerian hormone (AMH) levels, and the number of retrieved oocytes were significantly lower in women with prior salpingectomy than in women without tubal disease. Day-3 follicle-stimulating hormone (FSH) levels, total gonadotropin dosage, and stimulation days did not significantly differ between the groups. The indications of salpingectomy (i.e., hydrosalpinx and ectopic pregnancy) did not differ significantly in terms of ovarian response or reserve among women with salpingectomy history. A history of salpingectomy and other factors related to ovarian response in IVF, such as age, AMH, AFC, day-3 FSH, and total gonadotropin dose, were significantly correlated with the number of oocytes retrieved by univariate regression analysis. In the multivariate-adjusted model after controlling all the above-mentioned variables, only AFC and AMH levels continued to exhibit significant associations with the number of retrieved oocytes. In a subgroup analysis, the negative impact of prior salpingectomy on the number of retrieved oocytes was especially significant in women with suboptimal ovarian reserves (defined as AMH < 4 ng/mL), regardless of the indication of salpingectomy or whether salpingectomy was bilateral or unilateral.

CONCLUSION

A negative effect on the number of retrieved oocytes in the subsequent IVF cycle after salpingectomy is more likely in women aged <35 years with suboptimal ovarian reserve. Nevertheless, postsurgical AMH and AFC levels still possess a more direct predictive value on ovarian response than the history of salpingectomy.

Diagnostic laparoscopy prior to IVF cycle improves outcome in patients with unilateral distal tubal occlusion

OBJECTIVE

To assess the impact of laparoscopy before in vitro fertilization (IVF) treatment on live birth rates in patients with distal unilateral tubal obstruction (UTO).

METHODS

Retrospective cohort study which was conducted in tertiary ART center in Ankara University Hospital between January 2008- January 2019. Inclusion criteria were distal UTO at HSG, patients who were 18-40 years age and baseline serum FSH levels between 3-15 IU/ml. Exclusion criteria were patients who had previous tubal surgery and, hormonal dysfunction such as hyperprolactinemia or hypothyroidism at the time of the IVF cycle.

RESULTS

49 patients who underwent 117 IVF treatment cycles were included in the final analysis. Among those 17 patients (34 IVF cycles) in the study group who underwent laparoscopy prior to IVF cycles, and 32 patients (83 IVF cycles) in the control group who directly underwent IVF cycle with no prior laparoscopy. Eleven pathologies (64.7%) were detected and treated at laparoscopies of 17 patients with distal UTO. Both the clinical pregnancy and the live birth rates were also significantly higher in the study group when compared to the control group (29.4% vs. 12%, P=.031; 26.5% vs. 9.6%, respectively; P=.039).

CONCLUSIONS

Patients with distal UTO generally have a pelvic pathology and laparoscopy prior to IVF cycles can improve the treatment outcome.

Tubal patency assessment using sequential transvaginal ultrasound and hysterosalpingo-foam sonography after methotrexate treatment for tubal pregnancy

RESEARCH QUESTION

What is the efficacy of sequential two-dimensional transvaginal ultrasound (2D-US) and hysterosalpingo-foam sonography (HyFoSy) after methotrexate (MTX) treatment for tubal pregnancy among patients who desire a future pregnancy?

DESIGN

A prospective trial conducted between May 2019 and November 2020. Patients who had a suspected tubal ectopic pregnancy diagnosed by ultrasound and treated by MTX were included. These patients underwent sequential transvaginal 2D-US assessment of the pelvic organs and a complementary HyFoSy for tubal patency. The primary outcome was tubal obstruction in the affected side.

RESULTS

A total of 360 women underwent sequential transvaginal 2D-US assessment of the pelvic organs and a complementary HyFoSy for tubal patency. Of these, 40 (11.1%) women fulfilling the inclusion criteria were enrolled. In six out of 40 (15%), hydrosalpinx of the affected tube was found during the initial transvaginal ultrasound examination and were excluded from further investigation. In the remaining 34 (85%) patients, HyFoSy was carried out. Tubal block was found in 10 out of 34 (29.4%) patients. Of these, eight out of 34 (23.5%) and two out of 34 (5.9%) had a proximal block of the affected tube and bilateral proximal obstruction, respectively. Hysterosalpingography confirmed the tubal obstruction in all the affected cases. No procedure-related complications were documented.

CONCLUSIONS

Forty per cent of women who were treated by MTX for tubal pregnancy were diagnosed with tubal obstruction. We recommend that sequential transvaginal ultrasound and HyFoSy become part of routine follow-up for these women, thus offering them timely referral to the appropriate specialist.

Approaches to Improve Endometrial Receptivity in Case of Repeated Implantation Failures

Repeated implantation failures are a constant challenge in reproductive medicine with a significant impact both on health providers and on infertile couples. Several approaches have been proposed so far as effective; however, accumulative data have clarified that most of the treatment options do not have the evidence base for a generalized application to be suggested by the relevant societies. Implantation failures are attributed to either poor quality embryos or to defected endometrial receptivity. The current review aims to summarize in a systematic way all the new trends in managing RIF via interference with endometrial receptivity. The authors focus mainly, but not exclusively, on endometrial injury prior to embryo transfer and endometrial priming with autologous cells or biological agents. To this direction, a systematic search of the Pubmed database has been conducted taking into account the emerged evidence of the last two decades. All the suggested interventions are herein presented and analyzed in terms of reproductive outcomes. It is evident that properly powered and designed randomized trials are needed to support a new standard approach in RIF treatment that will safely be incorporated in national and international guidelines.

Secondary hydrosalpinx in adolescents: a challenging decision-making process for surgical choice and future fertility preservation

Hydrosalpinx in pre-pubertal children and non-sexually active adolescents is a rare finding with several etiology and negative impact on future female fertility. The therapeutic approach in these specific populations is debated and it must consider its etiology and adult guidelines focused on fertility issues, which suggest laparoscopic salpingectomy. We described two adolescent cases (15 years asymptomatic and 13 years with abdominal pain) presenting a monolateral hydrosalpinx secondary to surgery for Hirschsprung's disease and complicated appendicitis, respectively. Both patients underwent to uncomplicated robotic-assisted salpingectomy, with uneventful follow-up and preserved ovarian function. Robotic-assisted salpingectomy for hydrosalpinx secondary to previous surgical conditions is a safe and careful approach for adolescents in order to preserve ovarian vascularization, function and future fertility.

TUBAL FACTOR INFERTILITY: POSSIBLE OPTIONS OF REPRODUCTIVE FUNCTION RESTORATION

Relevance. Despite the assisted reproductive techniques being widely used in modern gynaecology, the challenge of restoring fallopian tube patency in patients with hydrosalpinx, distal tubal occlusion, peritubal and periovarial adhesions remains relevant.Objective. The aim of this study was to evaluate the effectiveness of laparoscopic surgery in restoring fertility in patients with tubal factor infertility.Materials and methods. We included 99 patients, who underwent laparoscopic surgery for tubal factor infertility. During the follow-up we assessed the rate of spontaneous pregnancy and pregnancy after IVF.Results. Pregnancy occurred in 41 (41.4%) patients with a history of tubal factor infertility. Moreover, after reconstructive plastic surgery on the fallopian tubes out of 66 patients, in 17 cases (25.8%) pregnancy occurred spontaneously. In 33 patients tubectomy was performed due to impossibility of adequate fallopian tube reconstruction. In 24 (24.2%) patients, pregnancy occurred after IVF (after salpingo-ovariolysis or after tubectomy). The frequency of pregnancy after IVF in these patients was 1,5 times higher than in patients that underwent IVF in the same medical institution during the same period (42.5% and 27.8%, respectively).Conclusion. In patients with tubal factor infertility younger than 35 with preserved ovulation and the absence of pathospermia in a partner, laparoscopy is an effective method for restoring patency of the fallopian tubes. If a severe falopian tube lesions are present in patients with infertility, bilateral tubectomy should be considered, since bilateral tubectomy in such patients increases the effectiveness of IVF.

Management of Hydrosalpinx in the Era of Assisted Reproductive Technology: A Systematic Review and Meta-analysis

OBJECTIVE

To conduct a systematic review and meta-analysis evaluating the effect of hydrosalpinx on pregnancy outcomes, to compare different types of management of hydrosalpinx and their impact on pregnancy rates as well as on the ovarian reserve.

DATA SOURCES

Electronic search using Pubmed, EMBASE, Ovid MEDLINE, Google Scholar, ClinicalTrials.gov, and Cochrane Central Register of Controlled Trials and including all published studies that examined tubal infertility and its management (assisted reproductive technology or surgery) as well as the effects on ovarian reserve. The following medical subject headings (Mesh) terms combinations were used: "fallopian tube disease," hydrosalpinx," "tubal or salpinx occlusion or obstruction," "in vitro fertilization," "fallopian tube surgery," "salpingectomy," "salpingostomy," "infertility," "subfertility," "sterility" and "ovarian reserve."

METHODS OF STUDY SELECTION

All randomized trials, cohort, and case controls studies were included. We excluded review articles, meeting abstracts, case series and case reports, and abstracts without access to full texts. The search was limited to trials in humans and published in English.

TABULATION, INTEGRATION, AND RESULTS

Our electronic search initially retrieved 6354 articles. Finally, 19 studies were included in the quantitative evaluation of the effects of hydrosalpinx: 23 in the qualitative evaluation and 5 in the quantitative evaluation of different types of hydrosalpinx treatments; and 17 in the quantitative evaluation of ovarian reserve. The presence of a hydrosalpinx was associated with decreased rates of implantation and clinical pregnancy, and increased rates of ectopic pregnancy and miscarriage. Management of hydrosalpinx with salpingectomy, tubal occlusion, or hydrosalpinx aspiration led to better in vitro fertilization pregnancy rates. We found no difference in ovarian response to stimulation after salpingectomy except a decrease in antimüllerian hormone compared to no surgery.

CONCLUSIONS

The presence of hydrosalpinx is associated with decreased pregnancy rate and increased rates of ectopic pregnancy and miscarriage. Management of hydrosalpinx, regardless of the type of treatment, leads to an increased chance of pregnancy.

Comparison of the efficacy between bilateral proximal tubal occlusion and total salpingectomy on ovarian reserve and the cholinergic system: an experimental study

Background and aim

To compare the effects of bilateral proximal tubal occlusion and bilateral total salpingectomy on ovarian reserve and the cholinergic system via rat experiment.

Materials and methods

Twenty-one adult female rats were randomly divided into the following three groups:G1 (n = 7), sham group;G2 (n = 7), bilateral total salpingectomy group; and G3 (n = 7), bilateral proximal tubal occlusion group. Four weeks later, the abdomen of the rats was opened. The right ovarian tissues were stored in 10% formaldehyde, whereas the left ovarian tissues were stored at –80 °C in aluminum foil. Serum samples were evaluated for antimullerian hormone. The right ovary was used for histological and immunoreactive examination, and the left ovary was used for tissue MDA analysis. Tissue samples were analyzed for MDA levels with spectrophotometric measurement, apoptosis with TUNEL staining, fibrosis score with Mason trichrome staining, ovarian reserve with HE staining, and cholinergic receptor muscarinic 1 (CHRM1) level with immunoreactivity method.

Results

Compared to G1 and G3, the number of corpus luteum with secondary follicles was significantly lower in G2, whereas the number of ovarian cysts and fibrosis and apoptosis scores increased significantly. The CHRM1 immunoreactivity was significantly lower in G2 than in G1 and G3.

Conclusions

Compared to the bilateral proximal tubal occlusion performed by using bipolar cautery, bilateral total salpingectomy in rats leads to a significant damage in ovarian histopathology and the cholinergic system.

Endometriosis and the Fallopian Tubes: Theories of Origin and Clinical Implications

Endometriosis is a common, oestrogen driven chronic condition, where endometrium-like epithelial and stromal cells exist in ectopic sites. At present, no curative treatments are available and the existing evidence for disease progression is conflicting. The pathogenesis is still unknown and evidently complex, as mechanisms of initiation may depend on the anatomical distribution of endometriotic lesions. However, amongst the numerous theories and plethora of mechanisms, contributions of the fallopian tubes (FT) to endometriosis are rarely discussed. The FT are implicated in all endometriosis associated symptomatology and clinical consequences; they may contribute to the origin of endometriotic tissue, determine the sites for ectopic lesion establishment and act as conduits for the spread of proinflammatory media. Here, we examine the available evidence for the contribution of the human FT to the origin, pathogenesis and symptoms/clinical consequences of endometriosis. We also examine the broader topic linking endometriosis and the FT epithelium to the genesis of ovarian epithelial cancers. Further studies elucidating the distinct functional and phenotypical characteristics of FT mucosa may allow the development of novel treatment strategies for endometriosis that are potentially curative.

Effects of three abnormal conditions of fallopian tube on outcomes of the in vitro fertilization and embryo transfer technique

AIM

The aim of this study was to demonstrate whether salpingitis affects the outcomes of in vitro fertilization and embryo transfer (IVF-ET).

METHODS

The retrospective study includes patients from 2013 to 2018 who received their first IVF-ET treatment during this period. On the basis of their tubal conditions, the patients were subgrouped as: hydrosalpinx (group A), salpingitis (group B), tubal occlusion (group C). It had a total of 726 cycles, of which 208 cycles were in group A, 201 cycles in group B and 317 cycles in group C. The outcomes of the IVF-ET treatment were compared amongst the three groups.

RESULTS

Group C had the highest number of retrieved oocytes as compared to the groups A and B, and the rate of the high-quality embryos at day 3 (66-68 h after insemination) was higher in the groups C and A compared to the group B. The blastocyst formation rate was significantly higher in group C compared to that of the group B. Group C had higher rates of implantation, clinical pregnancy and live birth compared to both groups A and B, while the birth weight of newborns did not differ amongst the three groups.

CONCLUSION

Salpingitis has adverse effects on the success rate of the IVF-ET treatment, exemplified by lower implantation, clinical pregnancy and live birth rates compared to tubal occlusion, it may be necessary to carry out appropriate management of salpingitis before IVF-ET treatment.

Suboptimal endometrial-embryonal synchronization is a risk factor for ectopic pregnancy in assisted reproduction techniques

RESEARCH QUESTION

What are the main risk factors associated with ectopic pregnancy and what is the true incidence of ectopic pregnancies in an IVF programme?

DESIGN

Retrospective single-centre study of 12,429 blastocyst transfers (8182 fresh and 4247 frozen embryo transfers) conducted between January 2010 and December 2017. IVF outcome was analysed, and ectopic pregnancy risk evaluated according to patient's characteristics and assisted reproductive technology treatment factors.

RESULTS

Of 5061 patients reporting a positive pregnancy test, 43 were diagnosed with ectopic pregnancy (0.85%). Neither female age (36.7 versus 35.8 years), body mass index, quality of transfer nor stimulation protocol affected the ectopic pregnancy rate, but history of previous ectopic pregnancy (OR 3.26; P = 0.0080), tubal surgery, or both (OR 6.20; P < 0.0001) did. The incidence of ectopic pregnancy was increased in women with uterine malformations (OR 3.85; P = 0.0052), uterine pathologies (OR 5.35; P = 0.0001), uterine surgeries (OR 2.29; P = 0.0154) or sub-optimal endometrial build-up (OR 4.46 to 5.31; P < 0.0001). Transfer of slow-developing blastocysts (expressed by expansion) significantly increased the risk of ectopic pregnancy (OR 2.59; P = 0.0102).

CONCLUSIONS

Unfavourable uterine environment, including uterine pathologies, uterine or tubal surgery and suboptimal endometrial build-up were related to ectopic pregnancy. Low expansion grade of blastocysts was identified as an additional putative risk factor for ectopic pregnancy, indicating the importance of proper embryonal-maternal synchronization. The overall ectopic pregnancy rate after blastocyst transfer was low, comparable with reported ectopic pregnancy rates in spontaneous conceptions. Proper evaluation of tubal and uterine pathologies, optimizing endometrial preparation and the transfer of expanded blastocysts in a frozen embryo transfer cycle, might be beneficial.