Effectiveness on fertility outcome of tubal flushing with different contrast media: systematic review and network meta-analysis

Contrast media for hysterosalpingography: systematic search and review providing new guidelines by the Contrast Media Safety Committee of the European Society of Urogenital Radiology

OBJECTIVES

Hysterosalpingography (HSG) is widely used for evaluating the fallopian tubes; however, controversies regarding the use of water- or oil-based iodine-based contrast media (CM) remain. The aim of this work was (1) to discuss reported pregnancy rates related to the CM type used, (2) to validate the used CM in published literature, (3) to discuss possible complications and side effects of CM in HSG, and (4) to develop guidelines on the use of oil-based CM in HSG.

METHODS

A systematic literature search was conducted for original RCT studies or review/meta-analyses on using water-based and oil-based CM in HSG with fertility outcomes and complications. Nine randomized controlled trials (RCTs) and 10 reviews/meta-analyses were analyzed. Grading of the literature was performed based on the Oxford Centre for Evidence-Based Medicine (OCEBM) 2011 classification.

RESULTS

An approximately 10% higher pregnancy rate is reported for oil-based CM. Side effects are rare, but oil-based CM have potentially more side effects on the maternal thyroid function and the peritoneum.

CONCLUSIONS

1. HSG with oil-based CM gives approximately 10% higher pregnancy rates. 2. External validity is limited, as in five of nine RCTs, the CM used is no longer on the market. 3. Oil-based CM have potentially more side effects on the maternal thyroid function and on the peritoneum. 4. Guideline: Maternal thyroid function should be tested before HSG with oil-based CM and monitored for 6 months after.

CLINICAL RELEVANCE STATEMENT

Oil-based CM is associated with an approximately 10% higher chance of pregnancy compared to water-based CM after HSG. Although side effects are rare, higher iodine concentration and slower clearance of oil-based CM may induce maternal thyroid function disturbance and peritoneal inflammation and granuloma formation.

KEY POINTS

• It is unknown which type of contrast medium, oil-based or water-based, is the optimal for HSG. • Oil-based contrast media give a 10% higher chance of pregnancy after HSG, compared to water-based contrast media. • From the safety perspective, oil-based CM can cause thyroid dysfunction and an intra-abdominal inflammatory response in the patient.

[Pregnancy after intrauterine insemination following hysterosalpingo-foam-sonography or hysterosalpingography]

OBJECTIVE

To compare clinical pregnancy rates following intrauterine insemination performed after hysterosalpingography (HSG) or hysterosalpingo-foam-sonography (HyFoSy).

MATERIAL AND METHODS

This is a retrospective study including 242 intrauterine insemination (IUI) performed between 2015 and 2020 at the fertility center of the Reunion Island. Among these inseminations, 121 with previous HSG and 121 with previous HyFoSy were matched. The main outcome of interest was clinical pregnancy rate. Secondary outcomes were birth rate and time to pregnancy after tubal patency test.

RESULTS

The pregnancy rate after insemination was 9.9% for the HSG group and 11.6% for the HyFoSy group, with no statistically significant difference between the groups (P=0.66). The live birth rate was similar in the two groups (7.4% for HSG and 10.7% for HyFoSy; P=0.37). Over half (57.1%) of the pregnancies occurred within 6 months after HyFoSy, whereas only 8.3% after HSG.

CONCLUSION

IUI results are not influenced by HyFoSy compared to HSG with regard to the pregnancy rates. Use of HyFoSy in infertility assessment allows global evaluation and more rapid adapted management. This approach could optimize management of patients undergoing IUI.

Impact of oil-based contrast agents in hysterosalpingography on fertility outcomes in endometriosis: a retrospective cohort study

BACKGROUND

Previous studies have suggested that oil-based contrast agents used during hysterosalpingography (HSG) in infertile patients can enhance fertility. However, limited research has investigated the effect of oil-based contrast medium specifically in individuals with endometriosis-related infertility.

OBJECTIVE

This study aims to explore the impact of oil-based contrast medium on fertility outcomes in women with endometriosis-related infertility.

METHODS

Conducted at the First Affiliated Hospital of Guangxi Medical University (January 2020 to June 2022), the study included 512 patients undergoing HSG. Patients were categorized into oil-based and non-oil-based groups, and after propensity score matching, demographic characteristics were compared. Main outcomes included clinical pregnancy rates, live birth rates, early miscarriage rates, and ectopic pregnancy rates.

RESULTS

In our analysis, the Oil-based group showed significantly better outcomes compared to the Non-oil-based group. Specifically, the Oil-based group had higher clinical pregnancy rates (51.39% vs. 27.36%) and increased live birth rates (31.48% vs. 19.93%). This trend held true for expectant treatment, IUI, and IVF/ICSI, except for surgical treatment where no significant difference was observed. After adjusting for various factors using propensity score matching, the Non-oil-based group consistently exhibited lower clinical pregnancy rates compared to the Oil-based group. The Odds Ratio (OR) was 0.38 (95%CI: 0.27-0.55) without adjustment, 0.34 (0.22-0.51) in multivariable analysis, 0.39 (0.27-0.57) using inverse probability of treatment weighting (IPTW), and 0.22 (0.14-0.35) in propensity score matching.

CONCLUSION

Oil-based contrast medium used in HSG for women with endometriosis-related infertility is associated with higher clinical pregnancy rates and live birth rates compared to Non-oil-based contrast medium.

Ultrasound-guided Lipiodol® hysterosalpingography: A prospective study on pregnancy and complication rates

BACKGROUND

Fluoroscopic hysterosalpingography (HSG) with Lipiodol® is safe and has a therapeutic effect on fertility: transient in endometriosis-related infertility and sustained in unexplained infertility. Ultrasound is replacing fluoroscopy as the preferred imaging modality for HSG due to comfort and radiation safety (no ionising radiation). The safety of ultrasound-guided Lipiodol® HSG is uncertain.

AIMS

Prospectively observe pregnancy and complication rates after ultrasound-guided Lipiodol® HSG.

MATERIALS AND METHODS

A single-centre prospective study of women with unexplained infertility undergoing ultrasound-guided Lipiodol® uterine bathing and tubal flushing after tubal patency confirmed with ExEm® Foam HyFoSy (hysterosalpingo-foam-sonography). Pregnancy outcomes at six months and serum and urinary thyroid function at one, three and eight weeks were recorded. Pain scores were recorded during and immediately after HSG. Descriptive statistics are reported.

RESULTS

Fifty-two participants were enrolled between July 2019 and April 2021, median age 33 years (range 21-45). Only 45 (87%, 45/52) completed the Lipiodol® HSG; 5/7 experienced intravasation during initial HyFoSy. Of 30 women at follow-up, 57% had biochemical (17/30, 95% CI 37%-75%), 53% clinical (16/30 95% CI 34%-72%) and 35% ongoing pregnancies (11/30, 95% CI 20%-56%). The rate of subclinical hypothyroidism (SCH) at two months was 41% (7/17). One intravasation event occurred during Lipiodol® HSG (2%, 1/45). Median pain score was 5/10 (range 0-9, interquartile range 2.5-7). No anaphylaxis, infection or oil embolism was observed.

CONCLUSION

Outpatient ultrasound-guided Lipiodol® HSG was safe, with pregnancy rates comparable to previous studies of fluoroscopic guidance. Rates of intravasation and SCH were also similar, confirming the need to monitor thyroid function.

Assessment of contrast intravasation in patients investigated by fluoroscopic hysterosalpingograms: A two-year retrospective audit in Western Australia

INTRODUCTION

Intravasation on hysterosalpingogram (HSG) is defined by the flow of injected contrast from the uterine cavity into adjacent myometrial vessels. Evidence suggests intravasation can result in consequences such as pulmonary and cerebral embolisms. However, adverse events are poorly reported across published studies. Reported intravasation ranges from 0.0% to 13%, with higher rates attributed to oil-soluble contrast medium (OSCM) use. Recent reviews of OSCM's fertility-enhancing benefits have prompted rapid clinical uptake by fertility specialists worldwide. This instigates increased concern for intravasation and its associated sequelae. We aim to assess the prevalence of intravasation in fluoroscopic HSGs and its reporting in Western Australia (WA).

METHODS

A two-year retrospective analysis of all fluoroscopic HSGs in one public teaching hospital within WA was conducted. All HSGs were retrieved from the public radiology information system and a blinded method was utilised to verify the presence and grading of intravasation in captured HSG images. Grading of intravasation was attributed by anatomical spread: 1 to myometrium, 2 to parametrium and 3 to para-iliac vessels. Results were subsequently compared with reported intravasation to assess for discrepancies.

RESULTS

Of 308 successful HSGs, an intravasation rate of 7.1% was identified. Of these cases, 45% were reported and 32% were graded. Majority (73%) of intravasation events were classified as grade 1, with 9.0% and 18% of cases classified as grade 2 and 3, respectively.

CONCLUSION

Under-reporting of intravasation emphasises a need for increased vigilance of radiologists. Standardised classification can provide interpretational consistency and should be considered to improve safety in future practice.

Effect of interval time between hysterosalpingography and intrauterine insemination on the pregnancy outcome of infertile patients

Background

Hysterosalpingography (HSG) is the most commonly applied tubal patency test in clinical practice. Although some studies have found an increased pregnancy rate after HSG, no studies to date have specifically characterized the effect of interval time between HSG and IUI on pregnancy outcome.

Objectives

To investigate the effect of interval time between HSG and intrauterine insemination (IUI) on live birth rates of infertile patients.

Methods

Retrospective cohort study. The reproductive medical record system was used to identify patients who completed ≥1 IUI cycle between January 2017 and October 2021. According to the interval time between HSG and IUI, patients were divided into three groups: <6months interval group,6-12 months interval group and >12 months interval group. The generalized estimating equation with Poisson distribution was used to estimate the risk ratios (RRs) and 95% confidence intervals (CIs) of different groups.

Results

A total of 413 patients completed 701 IUI cycles during the study period, <6months interval group, 415 cycles; 6-12 months interval group, 138 cycles; >12 months interval group, 148 cycles. The live birth rate of <6 months group was higher than other two groups (17.35% vs. 12.32% vs. 8.11%, P=0.017); Similarly, the clinical pregnancy rate of <6 months group was also higher than other two groups (19.76% vs. 14.49% vs.11.49%, P=0.049). When adjusted separately for FSH, AMH, infertility type, duration of infertility, infertility diagnosis, total motile count (TMC) of sperm, medications, endometrium size and dominant follicle size, the live birth rate of >12 months group severally significantly decreased by 60% (adjusted RR = 0.40, 95% CI [0.19-1.40]). The cumulative clinical pregnancy and live birth rates of <6 months group were higher than other two groups (P<0.05), but the cumulative pregnancy rate among three groups were not statistically different (log rank test: P=0.06).

Conclusion

The interval time between hysterosalpingography and IUI is related to pregnancy outcome. The clinical pregnancy and live birth rates were the highest when the time interval was less than 6 months. Therefore, IUI should be recommend as soon as possible after HSG if the patient couple meets the IUI indication.

Comparison of fertility outcomes between oil‑based and water‑based contrast media during hysterosalpingography: A meta‑analysis

Water-based and oil-based contrast media are both widely used in clinical practice for patients receiving hysterosalpingography (HSG). However, minor controversy exists about whether the oil-based contrast medium has a superior fertility-enhancing effect during HSG. The present meta-analysis intended to comprehensively compare the fertility outcomes of patients receiving either an oil-based or a water-based contrast medium during HSG. Web of Science, PubMed, Excerpta Medica Database, Cochrane, China National Knowledge Infrastructure, Wanfang Data and China Science and Technology Journal Database were examined for literature comparing the fertility enhancement between oil-based and water-based contrast media during HSG up to November 10, 2022 and there was no cut off for studies published earlier than any given year. Data for clinical pregnancy, ongoing pregnancy, live birth, miscarriage and ectopic pregnancy were extracted and analyzed. A total of 11 studies with 2,462 patients receiving oil-based contrast medium and 2,830 patients receiving water-based contrast medium during HSG were included. Relative risks (RRs) and 95% confidence intervals (CIs) were presented for outcome assessment, and the random effects model was utilized for all analyses. Publication bias was analyzed using Egger's and Begg's tests. The results indicated that the rate of clinical pregnancy was increased using oil-based contrast medium compared with water-based contrast medium [relative risk (RR) (95% CI), 1.29 (1.07, 1.54); P=0.006]. In addition, the rate of ongoing pregnancy [RR (95% CI), 1.39 (1.22, 1.59); P#x003C;0.001] and live birth [RR (95% CI), 1.41 (1.07, 1.87); P=0.016] were also increased using oil-based contrast medium compared with water-based contrast medium. However, miscarriage [RR (95% CI), 1.06 (0.61, 1.86); P=0.833] and ectopic pregnancy [RR (95% CI), 0.66 (0.18, 2.36); P=0.518] were not affected by using oil-based or water-based contrast medium. Begg's test and Egger's test suggested that no publication bias of clinical pregnancy, ongoing pregnancy, live birth, miscarriage and ectopic pregnancy existed (all P>0.05), which indicated the stability of the present meta-analysis. In conclusion, the oil-based contrast medium enhances fertility outcomes compared with the water-based contrast medium in patients receiving HSG.

Alternatives to in vitro fertilization

There have been concerns on the potential overuse of in vitro fertilization (IVF) in view of the lack of evidence on effectiveness in certain populations, potential short and long-term safety risks, and economic considerations. On the other hand, the use of alternatives to IVF seems to be underappreciated in clinical practice as well as research. In this review, we summarized the up-to-date evidence on the effectiveness, safety as well as cost-effectiveness of different alternatives to IVF, including expectant management, intrauterine insemination, tubal flushing, in vitro maturation as well as intravaginal culture. We also discussed the trend of IVF use over the last decade and the available tiers of service because of intravaginal culture, and revisited the roles of different alternatives to IVF in modern reproductive medicine from both clinical and research perspectives.

Intravasation complicating hysterosalpingo-foam sonography (HyFoSy) using ExEm® Foam

BACKGROUND

Transvaginal hysterosalpingo-foam sonography (HyFoSy) assesses tubal patency in an outpatient setting and without ionising radiation, unlike traditional hysterosalpingography (HSG) under fluoroscopy. Like HSG, HyFoSy may be complicated by uterine intramural contrast leak, leading to venous intravasation. Intravasation of particulate contrast agents risks pulmonary or cerebral emboli.

AIMS

We aimed to assess the intravasation rate of HyFoSy using ExEm® Foam and association with endometrial thickness, ExEm® Foam volume, uterine length, adenomyosis severity, uterine morphology or pain score.

METHODS

An ethics-approved retrospective study on all HyFoSy examinations between 23 January 2018 and 27 October 2021 on sub-fertile patients, trying to conceive. Initial transvaginal sonography confirmed anatomy, uterine morphology, adenomyosis severity and endometrial thickness. Subspecialist radiologists performed HyFoSy with sonographer assistance. Intravasation was identified in real time but also checked for afterwards. Patients were asked to rate instillation pain/discomfort from one to ten immediately afterward.

RESULTS

Four hundred and thirty-six (n = 436) patients met inclusion criteria. Thirty (6.9%) experienced intravasation. Endometrial thickness and pain score were associated with intravasation. For every millimetre increase in endometrial thickness, the odds of intravasation decreased by 26% (P = 0.010). For every point increase on the pain scale, the odds of intravasation increased by 22% (P = 0.032). There was no evidence of an association between instilled ExEm® Foam volume or the other previously published parameters with intravasation.

CONCLUSION

A 6.9% rate of intravasation was observed. Both endometrial thickness and pain score were significantly associated with intravasation. There was no evidence of an association between ExEm® Foam volume and intravasation.

The effectiveness of immediate versus delayed tubal flushing with oil-based contrast in women with unexplained infertility (H2Oil-timing study): study protocol of a randomized controlled trial

BACKGROUND

In women with unexplained infertility, tubal flushing with oil-based contrast during hysterosalpingography leads to significantly more live births as compared to tubal flushing with water-based contrast during hysterosalpingography. However, it is unknown whether incorporating tubal flushing with oil-based contrast in the initial fertility work-up results to a reduced time to conception leading to live birth when compared to delayed tubal flushing that is performed six months after the initial fertility work-up. We also aim to evaluate the effectiveness of tubal flushing with oil-based contrast during hysterosalpingography versus no tubal flushing in the first six months of the study.

METHODS

This study will be an investigator-initiated, open-label, international, multicenter, randomized controlled trial with a planned economic analysis alongside the study. Infertile women between 18 and 39 years of age, who have an ovulatory cycle, who are at low risk for tubal pathology and have been advised expectant management for at least six months (based on the Hunault prediction score) will be included in this study. Eligible women will be randomly allocated (1:1) to immediate tubal flushing (intervention) versus delayed tubal flushing (control group) by using web-based block randomization stratified per study center. The primary outcome is time to conception leading to live birth with conception within twelve months after randomization. We assess the cumulative conception rate at six and twelve months as two co-primary outcomes. Secondary outcomes include ongoing pregnancy rate, live birth rate, miscarriage rate, ectopic pregnancy rate, number of complications, procedural pain score and cost-effectiveness. To demonstrate or refute a shorter time to pregnancy of three months with a power of 90%, a sample size of 554 women is calculated.

DISCUSSION

The H2Oil-timing study will provide insight into whether tubal flushing with oil-based contrast during hysterosalpingography should be incorporated in the initial fertility work-up in women with unexplained infertility as a therapeutic procedure. If this multicenter RCT shows that tubal flushing with oil-based contrast incorporated in the initial fertility work-up reduces time to conception and is a cost-effective strategy, the results may lead to adjustments of (inter)national guidelines and change clinical practice.

TRIAL REGISTRATION NUMBER

The study was retrospectively registered in International Clinical Trials Registry Platform (Main ID: EUCTR2018-004153-24-NL).

A meta-analysis of fertility and adverse outcomes in oil- and water-based contrast for hysterosalpingography

Infertility is the inability to conceive after one year of regular unprotected intercourse. There is a debate about the therapeutic effect of hysterosalpingography (HSG) and whether the selection of contrast materials makes a difference in the chance of subsequent conception. In this study, we aimed to compare the fertility-enhancing outcomes and adverse effects of oil and water-based contrasts in patients who underwent HSG. This systematic review and meta-analysis was conducted following the PRISMA guidelines. We searched the Web of Science, PubMed, and Scopus until September 2022. We included all primary randomized controlled trials evaluating the fertility-enhancing benefits of HSG in oil-based versus water-based contrast media in women of childbearing age with infertility. Eleven studies with 4,739 patients were selected. The pregnancy rate in the oil group was significantly higher than that in the water group [odds ratio (OR)=1.51 (1.23, 1.86), p<0.0001]. Our meta-analysis favored the oil group in abdominal pain and vaginal bleeding with the odd ratios of 0.73 (0.58, 0.91), (p=0.006) and 0.91 (0.46, 1.81), (p=0.79), respectively. Water-based contrast was associated with less intravasation [OR=2.09 (1.09-4.02), p=0.03]. There were no differences between the contrasts for miscarriage [OR=1.02 (0.71, 1.46), p=0.92], and ectopic pregnancy [OR=0.84 (0.27, 2.63), p=0.77]. HSG with oil-based contrast was related to a higher pregnancy rate, live birth rate, and intravasation rate. While HSG using a water-based contrast medium was associated with increased abdominal discomfort, vaginal bleeding, and the visual-analogue scale pain score.

Is Hysterosalpingo-Contrast Sonography (HyCoSy) Using Sulfur Hexafluoride Microbubbles (SonoVue) Sufficient for the Assessment of Fallopian Tube Patency? A Systematic Review and Meta-Analysis

This study aimed to evaluate the diagnostic value of HyCoSy using sulfur hexafluoride microbubbles for fallopian tubal patency assessment in infertile females. Twenty-four studies, including 1358 females with 2661 detected fallopian tubes published from January 2003 to May 2019, were identified. The pooled sensitivity was 93% (95% CI: 90-95%), while the specificity was 90% (95% CI: 87-92%). The area under the receiver-operating characteristic curve was 0.96 (95% CI: 94-98%). The specificity of the four-dimensional HyCoSy subgroup was higher than the 2D/3D subgroup; an increased dose of contrast agent did not affect the specificity, with only a slightly reduced sensitivity.

Fertility-enhancing effect of oil-based contrast agents during hysterosalpingography and the variation of this effect within a 3-year follow-up period in infertile patients

Objective

The previous study has indicated the fertility-enhancing effect of oil-based contrast agents during hysterosalpingography (HSG) in infertile patients. However, the variation of this effect with the time frame is seldom reported. The current study aimed to explore fertility improvement using oil-based contrast agents and the change of this improvement during the 3-year follow-up period in infertile patients.

Materials and methods

Infertile women who underwent HSG with oil-based contrast agents (N = 500) or water-based contrast agents (N = 500) were enrolled. Spontaneous pregnancy rate and time to pregnancy were assessed at months (M)1, M2, M3, M6, M12, M24, and M36 after HSG.

Results

The spontaneous pregnancy rate was 79% in the oil-based group and 70.2% in the water-based group. The cumulative spontaneous pregnancy rate was increased in the oil-based group when compared with the water-based group (p = 0.015). Fertility-enhancing effect of HSG was increased in the oil-based group when compared with the water-based group at all time points {M1 [odds ratio (OR)]: 1.536}; M2 (OR: 1.455); M3 (OR: 1.494); M6 (OR: 1.356); M9 (OR: 1.288); M12 (OR: 1.249); M24 (OR: 1.131); and M36 (OR: 1.125). While this superiority of the fertility-enhancing effect of HSG in the oil-based group (vs. the water-based group) was decreased with the time frame. Similar findings were also observed based on the physiological cycles.

Conclusion

The HSG procedure with oil-based contrast agents shows a fertility-enhancing effect when compared to water-based contrast agents. This improvement could last at least 1 year while dropping to the normal level within the subsequent 2 years.

Modern assessment of the uterine cavity and fallopian tubes in the era of high-efficacy assisted reproductive technology

The high efficacy of modern assisted reproductive technology (ART) and increase in the number of noninfertile patients who are using ART for family building in the United States call into question the relevance of the standard, one-size-fits-all infertility evaluation. Here, we explore whether all patients presenting for ART need uterine cavity and tubal assessment and what tests are most appropriate, efficient, and cost-effective in current times.

Lipiodol flushing under ultrasound guidance at time of hystero-salpingo contrast sonography (HyCoSy): A retrospective observational study

BACKGROUND

Up to 30% of female infertility can be attributed to tubal abnormalities. Assessment of fallopian tube patency forms a component of the basic assessment of infertility. Tubal patency can be checked through hysterosalpingogram (HSG) under radiologic guidance with oil- or water-based contrast medium (OBCM or WBCM), or hystero-salpingo contrast sonography (HyCoSy) under ultrasound guidance with WBCM. Tubal flushing with OBCM has been shown to improve fertility rates.

OBJECTIVES

To study the feasibility and tolerability of performing Lipiodol (ethiodised oil) flush concurrently with HyCoSy. To examine the in vivo sonographic visibility of Lipiodol vs normal saline.

MATERIALS AND METHODS

Retrospective observational study of patients with subfertility referred for Lipiodol flushing under ultrasound guidance between August 2017-September 2020 at six private ultrasound practices in Sydney, Australia.

RESULTS

There were 412 patients who were referred for Lipiodol flushing. Of these, 86 patients did not have concurrent Lipiodol flush at HyCoSy performed due to strict exclusion criteria. Of the 326 patients who proceeded with Lipiodol flushing at HyCoSy, all cases were successful, with no cases of extravasation. There were no major complications. In vivo sonographic visualisation of Lipiodol was similar to that of the commonly used agitated 0.9% saline (n = 20; mean visibility score 4.3 ± 0.9 vs 4.0 ± 1.2).

CONCLUSION

Our study has shown that Lipiodol flushing at time of HyCoSy as a single procedure is feasible and tolerable to patients. Flushing with Lipioidol during HyCoSy is likely as sonographically visible as 0.9% saline.

Oil-based versus water-based contrast media for hysterosalpingography in infertile women of advanced age, with ovulation disorders or a high risk for tubal pathology: study protocol of a randomized controlled trial (H2Oil2 study)

Background

In women with unexplained infertility, tubal flushing with oil-based contrast during hysterosalpingography (HSG) increases ongoing pregnancy and subsequent live birth rates when compared to tubal flushing with water-based contrast. It is currently unclear whether an HSG with oil-based contrast also results in more ongoing pregnancies and live births in women of advanced age, women with ovulation disorders, and women with potential tubal pathology when compared to an HSG with water-based contrast.

Methods

We plan an international, multicentre, open-label, randomized controlled trial (RCT) studying three groups of infertile women who have an indication for tubal patency testing according to their treating physician and additionally; (1) are 39 years of age or older, (2) have an ovulation disorder or (3) have a high risk for tubal pathology based on their medical history. Women with an allergy for iodinated contrast medium are excluded, as are women with diabetes, hyperprolactinemia or untreated hyper- or hypothyroidism, and women with a partner with severe male infertility. After informed consent, women will be randomly allocated to the intervention, tubal flushing with the use of oil-based contrast during HSG or the control group, tubal flushing with the use of water-based contrast during HSG in a 1:1 ratio by the web-based system Castor. The primary endpoint will be ongoing pregnancy leading to live birth with conception within six months after randomization. Secondary outcomes are other pregnancy outcomes, used fertility treatments, adverse events and cost-effectiveness. Based on the expected ongoing pregnancy rate of 17% in the control group and 27% in the intervention group, the sample size will be 930 women (465 per group). Study inclusion is expected to be complete in four years.

Discussion

This multicentre RCT will establish whether, for women of advanced age, women with ovulatory disease, and women who have a high risk for tubal pathology, there is a fertility enhancing effect of tubal flushing with oil-based contrast during HSG and whether the use of this contrast medium is cost-effective.

Trial Registration The study was prospectively registered in the Netherlands Trial Register on August 1st 2019 as ‘H2Oil2’ (reference number NL7925, https://www.trialregister.nl/trial/7925).

Supplementary Information

The online version contains supplementary material available at 10.1186/s12905-022-01707-z.

Spontaneous pregnancy rates in infertile women after sequential hydrosonography and hysterosalpingo-foam sonography

OBJECTIVE

To determine the clinical pregnancy rate following sequential hydrosonography and hysterosalpingo-foam sonography (HyFoSy) in tubal patency assessment among women undergoing infertility work-up.

STUDY DESIGN

Prospective follow-up of women referred to our department between July 2019 and October 2020. Sequential hydrosonography and HyFoSy were carried out.

RESULTS

Out of 250 having the procedure, 100 women were excluded from study due to limited infertility, semen abnormal or not examined, evaluation for social egg freezing or they were single. Of the remaining 150 women, 48 (32%) conceived during a 10-24 months follow-up period: 17 (11%) conceived naturally and 7 (4.7%) by IUI. The mean time to conception was 5.5 ± 5.4 months and the pregnancy rate was 52% within 6 months. Among the spontaneous pregnancies 47% occurred within a month and 76% within 3 months.

CONCLUSION

Sequential hydrosonography and HyFoSy is a promising method for assessing the uterine cavity and tubal patency in women undergoing infertility workup. The findings suggest that the procedure may increase the chance of a spontaneous pregnancy following the procedure. Given the other known advantages of sequential hydrosonography and HyFoSy, this test is worth including in the initial workup for infertile patients.

Ethiodized poppyseed oil-based contrast medium is superior to water-based contrast medium during hysterosalpingography regarding image quality improvement and fertility enhancement: A multicentric, randomized and controlled trial

BACKGROUND

The efficacy of ethiodized poppyseed oil in hysterosalpingography (HSG) image quality and fertility enhancement has been revealed, but whether this HSG modality has similar effects in the Chinese population is still unclear.

METHODS

Between July 18, 2017, and December 29, 2019, this multicentric, randomized, two-arm, clinical trial was performed involving 15 medical centers. Infertile women meeting HSG indications were randomly assigned to an oil group and a water group. The coprimary outcome included HSG image quality during HSG and fertility-enhancing effects of HSG. This study was registered on ClinicalTrials.gov (NCT03370575).

FINDINGS

A total of 1026 subjects were randomly assigned to an oil group (N = 508) and a water group (N = 518). HSG image quality revealed that the oil group had outstanding visualization (all P < 0.001); total image quality scores for uterus opacification or uterine outline (2.9 ± 0.4 vs. 2.7 ± 0.5), fallopian tube outline (2.3 ± 0.8 vs. 1.7 ± 0.7), fimbrial rugae (1.7 ± 1.0 vs. 1.3 ± 0.8), fallopian tube spillage (2.1 ± 0.9 vs. 1.6 ± 0.8), peritoneal distribution (2.6 ± 0.9 vs. 2.1 ± 1.0) and diagnostic quality (11.6 ± 3.4 vs. 9.5 ± 3.1) (all P < 0.001) were higher in the oil group than in the water group. Regarding fertility-enhancing evaluation, the oil group showed an increased cumulative on-going pregnancy rate, on-going pregnancy within 6 months (29.1% vs. 20.1%), clinical pregnancy (39.5% vs. 29.1%) and live birth ≥ 24 weeks of gestation (36.1% vs. 27.7%) but a shorter time to pregnancy than the water group (all P < 0.01). Concerning adverse events, the oil group showed a lower occurrence rate of abdominal pain and vaginal bleeding after HSG (both P < 0.01).

INTERPRETATION

Ethiodized poppyseed oil-based contrast is superior to water-based contrast during HSG in terms of image quality improvement and fertility enhancement. This study indicates the priority of the application of ethiodized poppyseed oil-based contrast during the HSG procedure in infertile patients.

FUNDING

No funding was received.

OUP accepted manuscript

STUDY QUESTION

Does hysterosalpingo-foam sonography (HyFoSy) lead to similar pregnancy outcomes, compared with hysterosalpingography (HSG), as first-choice tubal patency test in infertile couples?

SUMMARY ANSWER

HyFoSy and HSG produce similar findings in a majority of patients and clinical management based on the results of either HyFoSy or HSG, leads to comparable pregnancy outcomes. HyFoSy is experienced as significantly less painful.

WHAT IS KNOWN ALREADY

Traditionally, tubal patency testing during fertility work-up is performed by HSG. HyFoSy is an alternative imaging technique lacking ionizing radiation and iodinated contrast medium exposure which is less expensive than HSG. Globally, there is a shift towards the use of office-based diagnostic methods, such as HyFoSy.

STUDY DESIGN, SIZE, DURATION

This multicentre, prospective, comparative study with a randomized design was conducted in 26 hospitals in The Netherlands. Participating women underwent both HyFoSy and HSG in randomized order. In case of discordant results, women were randomly allocated to either a management strategy based on HyFoSy or one based on HSG.

PARTICIPANTS/MATERIALS, SETTING, METHODS

We included infertile women between 18 and 41 years old who were scheduled for tubal patency testing during their fertility work-up. Women with anovulatory cycles not responding to ovulation induction, endometriosis, severe male infertility or a known iodine contrast allergy were excluded. The primary outcome for the comparison of the HyFoSy- and HSG-based strategies was ongoing pregnancy leading to live birth within 12 months after inclusion in an intention-to-treat analysis.

MAIN RESULTS AND THE ROLE OF CHANCE

Between May 2015 and January 2019, 1026 women underwent HyFoSy and HSG. HyFoSy was inconclusive in 97 of them (9.5%), HSG was inconclusive in 30 (2.9%) and both were inconclusive in 9 (0.9%). In 747 women (73%) conclusive tests results were concordant. Of the 143/1026 (14%) with discordant results, 105 were randomized to clinical management based on the results of either HyFoSy or HSG. In this group, 22 of the 54 women (41%) allocated to management based on HyFoSy and 25 of 51 women (49%) allocated to management based on HSG had an ongoing pregnancy leading to live birth (Difference −8%; 95% CI: −27% to 10%). In total, clinical management based on the results of HyFoSy was estimated to lead to a live birth in 474 of 1026 women (46%) versus 486 of 1026 (47%) for management based on HSG (Difference −1.2%; 95% CI: −3.4% to 1.5%). Given the pre-defined margin of −2%, statistically significant non-inferiority of HyFoSy relative to HSG could not be demonstrated (P = 0.27). The mean pain score for HyFoSy on the 1–10 Visual Analogue Scale (VAS) was 3.1 (SD 2.2) and the mean VAS pain score for HSG was 5.4 (SD 2.5; P for difference < 0.001).

LIMITATIONS, REASONS FOR CAUTION

Since all women underwent both tubal patency tests, no conclusions on a direct therapeutic effect of tubal flushing could be drawn.

WIDER IMPLICATIONS OF THE FINDINGS

HyFoSy or HSG produce similar tubal pathology findings in a majority of infertile couples and, where they differ, a difference in findings does not lead to substantial difference in pregnancy outcome, while HyFoSy is associated with significantly less pain.

STUDY FUNDING/COMPETING INTEREST(S)

The FOAM study was an investigator-initiated study funded by ZonMw, The Netherlands organization for Health Research and Development (project number 837001504). ZonMw funded the whole project. IQ Medical Ventures provided the ExEm-foam^® kits free of charge. The funders had no role in study design, collection, analysis and interpretation of the data. K.D. reports travel and speaker fees from Guerbet. F.J.M.B. reports personal fees as a member of the external advisory board for Merck Serono, The Netherlands, and a research support grant from Merck Serono, outside the submitted work. C.B.L. reports speakers’ fee from Ferring in the past, and his department receives research grants from Ferring, Merck and Guerbet. J.S. reports a research agreement with Takeda on MR of motility outside the submitted work. M.V.W. reports leading The Netherlands Satellite of the Cochrane Gynaecology and Fertility Group. B.W.J.M. is supported by an NHMRC Investigator grant (GNT1176437). B.W.J.M. reports consultancy for Guerbet and research funding from Merck and Guerbet. V.M. reports non-financial support from IQ medicals ventures, during the conduct of the study; grants and personal fees from Guerbet, outside the submitted work. The other authors do not report conflicts of interest.

TRIAL REGISTRATION NUMBER

NTR4746/NL4587 (https://www.trialregister.nl)

TRIAL REGISTRATION DATE

19 August 2014

DATE OF FIRST PATIENT’S ENROLMENT

7 May 2015

Live birth after additional tubal flushing with oil-based contrast versus no additional flushing: a randomised, multicentre, parallel-group pragmatic trial in infertile women with at least one patent tube at hysterosalpingo-foam sonography (HYFOIL study)

INTRODUCTION

Tubal patency testing is an essential part in the fertility workup of many subfertile women. Hysterosalpingography (HSG) has long been the test of choice in many clinics. There is evidence from a large randomised multicentre trial and from a recent meta-analysis that women who had HSG using oil soluble contrast medium (OSCM) had higher rates of ongoing pregnancy compared with women who underwent this procedure using water contrast. However, the field is moving away from HSG and nowadays hysterosalpingo-foam sonography (Hyfosy) using ultrasound guidance is considered as the first line office tubal patency test. Therefore, a large multicentre randomised clinical trial (RCT) will be initiated to evaluate if flushing the fallopian tubes with OSCM after a normal Hyfosy showing at least one patent fallopian tube will increase the live birth rate as compared with no flushing.

METHODS AND ANALYSIS

We plan a multicentre two arm, 1:1 randomised, open-label pragmatic comparative trial in 12 Belgian centres. After informed consent, we will randomise infertile women between 18 and 40 years of age, undergoing Hyfosy as part of the fertility workup to Hyfosy with additional tubal flushing with OSCM versus Hyfosy without additional flushing. Infertility is defined as lack of conception despite 12 months of unprotected intercourse, or three cycles of donor insemination without pregnancy or three ovulatory ovulation induction cycles without pregnancy, all three in combination with at least one patent tube on Hyfosy. Primary endpoint will be live birth with conception within 6 months after randomisation.

ETHICS AND DISSEMINATION

Approval on 11 May 2021 by the Ethics Committee from ZNA Hospital Antwerp who was the central Ethics Committee for the Clinical Trial Regulation Pilot (Pilot 412) in the 12 centres. The findings from this RCT will be disseminated in peer-reviewed publications and presentations at scientific international meetings.

TRIAL REGISTRATION NUMBERS

EudraCT number: 2020-002135-30 and NCT04379973.

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.

Magnetic Resonance Imaging Feature Analysis and Evaluation of Tubal Patency under Convolutional Neural Network in the Diagnosis of Infertility

To explore the diagnostic value of MRI image features based on convolutional neural network for tubal unobstructed infertility, 30 infertile female patients were first selected as the research objects, who admitted to the hospital from May 2018 to January 2020. They all underwent routine MRI examinations and CNN-based MR-hysteron-salpingography (HSG) examinations, in order to discuss the diagnostic accuracy of the two examinations. In the research, it was necessary to observe the patients' imaging results, calculate the diagnosis rate of the two examination results, and analyze the application effect of the CNN algorithm, thereby selecting the best reconstruction method. In this study, the analysis was conducted on the basis of no statistical difference in the baseline data of the included patients. The results of undersampling reconstruction at 2-fold, 4-fold, and 6-fold showed that CNN for data consistency layer (CNN_DC) had a better effect, and its peak signal-to-noise ratio (PSNR) was lower sharply than that of the other two reconstruction methods, while the normalized mean square error (NMSE) and structural similarity index measure (SSIM) were higher markedly than the values of the other two reconstruction methods. The diagnostic rate of routine MRI examination of the fallopian tube and other parts of the uterus was lower than or equal to that of MR-HSG examination by CNN. Routine MRI examinations of fallopian tube imaging artifacts were large, and the definition was reduced, which increased the difficulty of identification. However, MR-HSG examination by CNN indicated that the imaging artifacts were low, the clarity was high, and the influence of noise was small, which was conducive to clinical diagnosis and identification. For endometriosis, the accuracy of MR-HSG was 33.33% and the accuracy of MRI was 46.67%. CNN MR-HSG inspection method was significantly better than the conventional MRI inspection method (P < 0.05). Therefore, the results of this study revealed that MR-HSG examination by CNN had a clear imaging effect and obvious inhibition effect on background signals and rapid image generation without the need for reconstruction with the same spatial resolution, which improved the imaging quality and could provide a reference value for clinical diagnosis and subsequent related studies.

Evaluating Fallopian Tube Patency: What the Radiologist Needs to Know

Impaired tubal patency accounts for up to 35% of cases of subfertility and infertility. Hysterosalpingography (HSG) or hysterosalpingo-contrast sonography (HyCoSy) represents a first-line test in evaluating fallopian tube patency. Despite the association of HSG with ionizing radiation, HSG is a reference standard in assessing fallopian tube patency and tubal conditions such as tubal occlusion, salpingitis isthmica nodosa, and hydrosalpinx. HSG is widely available and utilizes either a water-soluble contrast medium (WSCM) or an oil-soluble contrast medium (OSCM). Compared with WSCM, HSG with OSCM results in a higher incidence of non-in vitro fertilization pregnancies and, therefore, may be preferred in women younger than 38 years with unexplained subfertility. HSG may also be helpful in assessment after sterilization or before fallopian tube recanalization. US-based tubal tests are free of ionizing radiation and include HyCoSy, with either air-saline or microbubble US contrast material, and hysterosalpingo-foam sonography (HyFoSy), a tubal patency test that utilizes a gel foam. A comprehensive US infertility evaluation of the pelvis and fallopian tubes can be achieved in one setting by adding coronal three-dimensional imaging of the uterus, saline infusion sonohysterography, and HyCoSy or HyFoSy to routine pelvic US. MR HSG and virtual CT HSG also depict tubal patency and uterine and adnexal pathologic conditions and may be considered in select patients. While laparoscopic chromopertubation remains the standard for tubal patency evaluation, its disadvantages are its invasiveness and cost. Knowledge of the different fallopian tube tests and radiologic appearance of normal and abnormal fallopian tubes results in fewer pitfalls, accurate interpretation, and optimal patient care. Online supplemental material is available for this article. ^©RSNA, 2021.

Cost-effectiveness modelling of three different hysterosalpingography diagnostic strategies in addition to standard fertility management for couples with unexplained infertility in the United Kingdom

Previous studies have demonstrated hysterosalpingography (HSG) in general, and specifically with an oil-soluble contrast medium, directly increases pregnancy rates. Decision modelling was performed to compare fertility management using three HSG diagnostic strategies: (i) water-soluble contrast medium (WSCM)-HSG; (ii) Lipiodol® Ultra Fluid (LUF)-HSG; and (iii) No HSG, for women aged ≤39 years with unexplained infertility. Four reimbursement scenarios were modelled to reflect the various funding arrangements across the regions of the United Kingdom. Compared with WSCM-HSG, the live birth rates after 24 months increased by 3.4% with LUF-HSG and decreased by 2.7% with no HSG. From a patient perspective, fertility management with LUF-HSG is the most cost-effective strategy with cost-savings ranging from £299 to £857 per patient depending on the funding arrangement for IVF. From an NHS perspective, fertility management with LUF-HSG is cost-effective when 2 or more IVF cycles are NHS-funded. If none of the IVF cycles are NHS-funded, fertility management with LUF-HSG can be considered cost-effective if society is willing to pay £8,353 for an additional live birth. The findings from this analysis suggest that fertility management with WSCM-HSG is cost-effective compared to no HSG and LUF-HSG is the most cost-effective with increased live birth rates after 24 months.

The value of transvaginal 4-dimensional hysterosalpingo-contrast sonography in predicting the necessity of assisted reproductive technology for women with tubal factor infertility

Background

More than 50 million women suffer from infertility worldwide, among whom 30% have associated fallopian tube pathology. Fortunately, the diagnostic accuracy of tubal patency has been enhanced with the consistent development of ultrasound imaging technology, especially the invention of transvaginal 4-dimensional hysterosalpingo-contrast sonography (TV 4D HyCoSy). However, detailed imaging data for evaluating the tubal condition for spontaneous conception and assessing the necessity of assisted reproductive technology (ART) have yet to be amassed.

Methods

Patients with tubal factor infertility (TFI) who received TV 4D HyCoSy were recruited for this study. They were divided into two groups according to the method of conception: the natural pregnancy group (patients who naturally conceived within 3 months after TV 4D HyCoSy) and the assisted reproduction group (patients who failed to conceive naturally within the 3 months but successfully conceived through ART). Logistic regression analysis was performed to examine the data obtained from participants' medical history and TV 4D HyCoSy investigation.

Results

Of the initial 1,433 women, 348 were excluded due to exclusion criteria or lack of follow-up. A total of 1,085 TFI patients were finally included, with individuals in the natural pregnancy group accounting for 27.74% (n=301), and those in the ART group accounting for 37.33% (n=405). The age was younger and the duration of infertility was shorter in the group of women who conceive spontaneously after TV 4D HyCoSy (P<0.05). In terms of imaging data, their endometrial thickness was thinner, right fallopian tube wall was more intact, morphology of the right fallopian tube was smoother, and their ovarian motility (bilateral), fallopian tube visualization (bilateral) and overflow condition of the contrast agent from the fimbriae of fallopian tube (bilateral) were better. In addition, the resistance of the contrast agent injection was less likely to be persistent, reflux was less likely to happen and 0/1 dispersion of the contrast agent around the ovary (bilateral) were more likely to be annular (P<0.05).

Conclusions

The imaging data gathered from TV 4D HyCoSy in TFI patients were comprehensive, which suggested that TV 4D HyCoSy could have potential to be used to assess the necessity of post-HyCoSy ART intervention in patients with TFI. This could be of benefit in reducing the incidence of overtreatment and potential complications of ART.

Therapeutic effects of hysterosalpingography contrast media in infertile women: what do we know about the H2O in the H2Oil trial and why does it matter?

Recent interest in the use of oil-soluble contrast media (OSCM) for hysterosalpingography (HSG) and other tubal flushing procedures is largely the result of publication of the large, multicentre, randomized controlled H2Oil trial in the New England Journal of Medicine in 2017, addressing the long-held suspicion that pregnancy rates following HSG with OSCM are higher than if a water-soluble contrast media (WSCM) is used. However, the findings of this trial have been compromised by the WSCM selected for comparison with OSCM. The chosen WSCM belongs to a superceded class of ionic media, with an iodine concentration, osmolality and viscosity all lying at the extreme end of the range for water-soluble radiographic contrast. The requirement for safe, cheap, versatile WSCM for intravascular use during computerized tomography, angiography and interventional procedures has resulted in considerable refinement of WSCM, with current widespread use of non-ionic, low osmolality or iso-osmolar WSCM in radiology, including for HSG. However, the use of the earlier ionic, high osmolality agents such as that selected for the H2Oil trial persists for HSG in some centres, despite potential adverse effects on the endometrium and fallopian tubal epithelium compared with more modern, less toxic WSCM. Knowledge of the variety of physical and chemical characteristics of the available WSCM is essential for interpretation of the current literature and establishing the most effective and safe water-soluble agent to use for HSG. Design of future clinical trials to establish the potential superiority of OSCM over WSCM for fertility enhancement must include the use of the readily available, inexpensive modern WSCM. While the fertility rates following OSCM HSG have been shown to be high in women with idiopathic infertility, more robust trials are required before the widespread use of OSCM for HSG or other modalities such as ultrasound and laparoscopy should be adopted.

Thyroid function in neonates conceived after hysterosalpingography with iodinated contrast

STUDY QUESTION

Does exposure to preconceptional hysterosalpingography (HSG) with iodinated oil-based contrast affect neonatal thyroid function as compared to iodinated water-based contrast?

SUMMARY ANSWER

Preconceptional HSG with iodinated contrast did not influence the neonatal thyroid function.

WHAT IS KNOWN ALREADY

HSG is a commonly applied tubal patency test during fertility work-up in which either oil- or water-based contrast is used. Oil-based contrast contains more iodine compared to water-based contrast. A previous study in an East Asian population found an increased risk of congenital hypothyroidism (CH) in neonates whose mothers were exposed to high amounts of oil-based contrast during HSG.

STUDY DESIGN, SIZE, DURATION

This is a retrospective data analysis of the H2Oil study, a randomized controlled trial (RCT) comparing HSG with the use of oil- versus water-based contrast during fertility work-up. After an HSG with oil-based contrast, 214 women had an ongoing pregnancy within 6 months leading to a live birth compared to 155 women after HSG with water-based contrast.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Of the 369 women who had a live born infant, 208 consented to be approached for future research and 138 provided informed consent to collect data on the thyroid function tests of their offspring (n = 140). Thyroid function tests of these children were retrieved from the Dutch neonatal screening program, which includes the assessment of total thyroxine (T4) in all newborns, followed by thyroid-stimulating hormone only in those with a T4 level of ≤ -0.8 SD score. Furthermore, amount of contrast medium used and time between HSG and conception were compared between the two study groups.

MAIN RESULTS AND THE ROLE OF CHANCE

Data were collected from 140 neonates conceived after HSG with oil-based (n = 76) or water-based (n = 64) contrast. The median T4 concentration was 87.0 nmol/l [76.0-96.0] in the oil group and 90.0 nmol/l [78.0-106.0] in the water group (P = 0.13). None of the neonates had a positive screening result for CH.The median amount of contrast medium used was 9.0 ml [interquartile range (IQR), 6.0-11.8] in the oil-group and 10.0 ml [IQR, 7.5-14.0] in the water group (P = 0.43). No influence of the amount of contrast on the effect of contrast group on T4 concentrations was found (P-value for interaction, 0.37).

LIMITATIONS, REASONS FOR CAUTION

A relatively small sample size and possible attrition at follow-up are limitations of this study. Although our results suggest that the use of iodinated contrast media for HSG is safe for the offspring, the impact of a decrease in maternal thyroid function on offspring neurodevelopment could not be excluded, as data on maternal thyroid function after HSG and during conception were lacking.

WIDER IMPLICATIONS OF THE FINDINGS

As HSG with oil-based contrast does not affect thyroid function of the offspring, there is no reason to withhold this contrast to infertile women undergoing HSG. Future studies should investigate whether HSG with iodinated contrast influences the periconceptional maternal thyroid function and, consequently, offspring neurodevelopment.

STUDY FUNDING/COMPETING INTEREST(S)

This study received no funding. The original H2Oil RCT was an investigator-initiated study that was funded by the two academic institutions (Academic Medical Center and VU University Medical Center) of the Amsterdam UMC. The funders had no role in study design, collection, analysis and intrepretation of the data. I.R. reports receiving travel fee from Guerbet. C.B.L. reports speakers fee from Ferring in the past and research grants from Ferring, Merck and Guerbet. K.D. reports receiving travel fee and speakers fee from Guerbet. B.W.M. is supported by a NHMRC Practitioner Fellowship (GNT1082548). B.W.M. reports consultancy for ObsEva, Merck KGaA and Guerbet and travel and research grants from Merck KGaA and Guerbet. V.M. reports receiving travel fee and speakers fee as well as research grants from Guerbet. The other authors do not report conflicts of interest.

TRIAL REGISTRATION NUMBER

Netherlands Trial Register NTR 7526 (Neonates born after the H2Oil study), NTR 3270 (original H2Oil study), www.trialregister.nl.

Gynaecological and IVF procedures billed through the Medicare Benefits Schedule (MBS) during the COVID-19 pandemic

Background

In response to the COVID‐19 pandemic in Australia, restrictions to elective surgeries were implemented nationwide.

Aims

To investigate the response to these restrictions in elective gynaecological and In vitro fertilisation (IVF) procedures during the first wave of the COVID‐19 pandemic.

Materials and Methods

We analysed the Medicare Item Reports for the number of elective gynaecological (labioplasty, vulvoplasty; prolapse and continence; operative hysteroscopy; hysterectomy; fertility) and IVF procedures claimed in Australia between January–June 2020 and compared these to January–June 2019.

Results

The number of included gynaecological and IVF procedures performed in January–June 2020 decreased by −13.71% and −12.56%, respectively, compared to January–June 2019. The greatest reductions were in May 2020 (gynaecology −43.71%; IVF −51.63% compared to May 2019), while April 2020 reported decreases of −37.69% and −31.42% in gynaecological and IVF procedures, respectively. In April 2020, 1963 IVF cycle initiations (−45.20% compared to April 2019), 2453 oocyte retrievals (−26.99%) and 3136 embryo transfers (−22.95%) were billed. The procedures with greatest paired monthly decrease were prolapse and continence surgeries in April (676 procedures; −51.85%) and May 2020 (704 procedures; −60.05%), and oocyte retrievals in May 2020 (1637 procedures; −56.70%).

Conclusions

While we observed a decrease in procedural volumes, elective gynaecological and IVF procedures continued in considerable numbers during the restricted timeframes. In the event of future overwhelming biological threat, careful consideration must be given to more effective measures of limiting access for non‐emergency procedures to conserve essential resources and reduce risk to both the public and healthcare staff.

Safety of oil-based contrast medium for hysterosalpingography: a systematic review

Recent meta-analyses have shown that a hysterosalpingography (HSG) with oil-based contrast increases pregnancy rates in subfertile women. However, the frequency of complications during or after an HSG with oil-based contrast in subfertile women and/or their offspring is still unclear. This systematic review and meta-analysis, without restrictions on language, publication date or study design, was performed to fill this knowledge gap. The results show that the most frequently reported complication was intravasation of contrast, which occurred in 2.7% with the use of oil-based contrast (31 cohort studies and randomized controlled trials [RCT], 95% CI 1.7-3.8, absolute event rate 664/19,339), compared with 2.0% with the use of water-based contrast (8 cohort studies and RCT, 95% CI 1.2-3.0, absolute event rate 18/1006). In the cohort studies and RCT there were 18 women with an oil embolism (18/19,339 HSG), all without serious lasting consequences. Four cases with serious consequences of an oil embolism were described (retinal oil embolism [n = 1] and cerebral complaints [n = 3]); these reports did not describe the use of adequate fluoroscopy guidance during HSG. In conclusion, the most frequently reported complication after an HSG with oil-based contrast is intravasation occurring in 2.7%. In total four cases with serious consequences of oil embolisms in subfertile women were published.

Tubal Flushing Treatment for Unexplained Infertility

Tubal patency testing was initially introduced as a diagnostic test. However, it has been observed that some tubal patency tests also have a therapeutic effect. This therapeutic effect can be influenced by the contrast medium used during tubal flushing. In this review, we discuss current evidence associated with different methods for tubal flushing and their potential impact on reproductive outcomes in women with unexplained infertility. Furthermore, we discuss their diagnostic accuracy, safety, and cost-effectiveness.

Tubal flushing for subfertility

BACKGROUND

Establishing the subgroup analysis of the fallopian tubes (tubes) is a commonly undertaken diagnostic investigation for women with subfertility. This is usually achieved by flushing contrast medium through the tubes and visualising patency on radiographs, ultrasonography or laparoscopy. Many women were noted to conceive in the first three to six months after tubal flushing, raising the possibility that tubal flushing could also be a treatment for infertility. There has been debate about which contrast medium should be used (water-soluble or oil-soluble media) as this may influence pregnancy rates. An important adverse event during tubal flushing is intravasation (backflow of contrast medium into the blood or lymphatic vessels),which could lead to embolism although it is asymptomatic in most cases.

OBJECTIVES

To evaluate the effectiveness and safety of tubal flushing with oil-soluble contrast media (OSCM) and water-soluble contrast media (WSCM) on subsequent fertility outcomes in women with subfertility.

SEARCH METHODS

We searched the Cochrane Gynaecology and Fertility Group Specialised Register of controlled trials, MEDLINE, Embase, CENTRAL, PsycINFO, reference lists of identified articles and trial registries. The most recent search was conducted in April 2020.

SELECTION CRITERIA

Randomised controlled trials (RCTs) comparing tubal flushing with OSCM, WSCM with each other or with no treatment, in women with subfertility.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected the trials, assessed risk of bias and extracted data. We contacted study authors for additional information. The overall quality of the evidence was assessed using GRADE methods.

MAIN RESULTS

Fifteen trials involving 3864 women were included in this systematic review. Overall, the quality of evidence varied from very low to moderate: the main limitations were risk of bias, heterogeneity and imprecision. OSCM versus no treatment Four studies (506 women) were included in this comparison. Tubal flushing with OSCM may increase the odds of live birth (odds ratio (OR) 3.27, 95% confidence interval (CI) 1.57 to 6.85, 3 RCTs, 204 women, I² = 0, low-quality evidence). This suggests that if the chance of live birth following no treatment is assumed to be 11%, the chance following tubal flushing with OSCM would be between 16% and 46%. Tubal flushing with OSCM may increase in the odds of clinical pregnancy (OR 3.54, 95% CI 2.08 to 6.02, 4 RCTs, 506 women, I² = 18%, low-quality evidence). This suggests that if the chance of clinical pregnancy following no treatment is assumed to be 9%, the chance following tubal flushing with OSCM would be between 17% and 37%. No study measured intravasation or other adverse events such as infection, haemorrhage and congenital abnormalities. WSCM versus no treatment Only one study (334 women) was included in this comparison. We are uncertain whether tubal flushing with WSCM increase live birth compared to no treatment (OR 1.13, 95% CI 0.67 to 1.91, 1 RCT, 334 women, low-quality evidence). This suggests that if the chance of live birth following no treatment is assumed to be 21%, the chance following tubal flushing with WSCM would be between 15% and 33%. We are uncertain whether tubal flushing with WSCM increases clinical pregnancy compared to no treatment (OR 1.14, 95% CI 0.71 to 1.84, 1 RCT, 334 women, low-quality evidence). This suggests that if the chance of clinical pregnancy following no treatment is assumed to be 27%, the chance following tubal flushing with WSCM would be between 29% and 40%. One case with pelvic infection was reported in the WSCM group and no case with infection in the no treatment group in a one study (334 women). Meta-analysis was not performed due to the rare events. No study measured intravasation or other adverse events such as infection, haemorrhage and congenital abnormalities. OSCM versus WSCM Six studies (2598 women) were included in this comparison. Three studies reported live birth, including two with higher live birth in the OSCM group (OR 1.64, 95% CI 1.27 to 2.11, 1119 women; OR 3.45, 95% CI 1.97 to 6.03, 398 women); and one with insufficient evidence of a difference between groups (OR 0.92, 95% CI 0.60 to 1.40, 533 women). Given the substantial heterogeneity observed (I² = 86%), meta-analysis was not performed. Tubal flushing with OSCM probably increased in the odds of intravasation (asymptomatic) compared to tubal flushing with WSCM (OR 5.00, 95% CI 2.25 to 11.12, 4 RCTs, 1912 women, I² = 0, moderate-quality evidence). This suggests that if the chance of intravasation following tubal flushing with WSCM is assumed to be 1%, the chance following tubal flushing with OSCM would be between 2% and 9%. Tubal flushing with OSCM may increase the odds of clinical pregnancy (OR 1.42, 95% CI 1.10 to 1.85, 6 RCTs, 2598 women, I² = 41%, low-quality evidence). This suggests that if the chance of clinical pregnancy following tubal flushing with WSCM is assumed to be 26%, the chance following tubal flushing with OSCM would be between 28% and 39%. We are uncertain whether tubal flushing with OSCM decreases the odds of infection (OR 0.22, 95% CI 0.04 to 1.22, 2 RCTs, 662 women, I² = 0, very low-quality evidence) or haemorrhage (OR 0.65, 95% CI 0.40 to 1.06, 2 RCTs, 662 women, I² = 0, very low-quality evidence). Three neonates with congenital abnormalities were reported in the OSCM group while no congenital abnormality was reported in the WSCM group in one study (1119 women). No meta-analysis was performed due to the rare events.

AUTHORS' CONCLUSIONS

The evidence suggests that compared to no treatment, tubal flushing with OSCM may increase the chance of live birth and clinical pregnancy, while it is uncertain whether tubal flushing with WSCM improves those outcomes. Compared to tubal flushing with WSCM, OSCM may improve clinical pregnancy while meta-analysis was impossible for live birth due to heterogeneity. Evidence also suggests that OSCM is associated with an increased risk of asymptomatic intravasation. Overall, adverse events, especially long-term adverse events, are poorly reported across studies.

The long-term costs and effects of tubal flushing with oil-based versus water-based contrast during hysterosalpingography

RESEARCH QUESTION

What are the long-term costs and effects of oil- versus water-based contrast in infertile women undergoing hysterosalpingography (HSG)?

DESIGN

This economic evaluation of a long-term follow-up of a multicentre randomized controlled trial involved 1119 infertile women randomized to HSG with oil- (n = 557) or water-based contrast (n = 562) in the Netherlands.

RESULTS

In the oil-based contrast group, 39.8% of women needed no other treatment, 34.6% underwent intrauterine insemination (IUI) and 25.6% had IVF/intracytoplasmic sperm injection (ICSI) in the 5 years following HSG. In the water-based contrast group, 35.0% of women had no other treatment, 34.2% had IUI and 30.8% had IVF/ICSI in the 5 years following HSG (P = 0.113). After 5 years of follow-up, HSG using oil-based contrast resulted in equivalent costs (mean cost difference -€144; 95% confidence interval [CI] -€579 to +€290; P = 0.515) for a 5% increase in the cumulative ongoing pregnancy rate compared with HSG using water-based contrast (80% compared with 75%, Relative Risk (RR) 1.07; 95% CI 1.00-1.14). Similarly, HSG with oil-based contrast resulted in equivalent costs (mean cost difference -€50; 95% CI -€576 to +€475; P = 0.850) for a 7.5% increase in the cumulative live birth rate compared with HSG with water-based contrast (74.8% compared with 67.3%, RR 1.11; 95% CI 1.03-1.20), making it the dominant strategy. Scenario analyses suggest that the oil-based contrast medium is the dominant strategy up to a price difference of €300.

CONCLUSION

Over a 5-year follow-up, HSG with an oil-based contrast was associated with a 5% increase in ongoing pregnancy rate, a 7.5% increase in live birth rate and similar costs to HSG with water-based contrast.

Lipiodol flush under ultrasound guidance in Australia

BACKGROUND

Lipiodol tubal flushing is offered to select subfertile women primarily to confirm tubal patency and to increase pregnancy rates.

AIMS

To investigate the safety of hystero-salpingo contrast sonography (HyCoSy) using Lipiodol flush (through frequency of adverse events and mean recalled pain score) and secondarily to quantify pregnancy rates.

MATERIALS AND METHODS

Retrospective observational Phase 1 study of subfertile women in three centres across Australia between June 2017 and June 2019. Cases were identified from medical records, and women telephoned to assess adverse outcomes, procedure tolerability and confirm pregnancy outcomes within six months from procedure.

RESULTS

A total of 325 cases were identified; 14 were excluded due to incomplete or abandoned procedure, 32 were lost to follow-up, leaving 279 for analysis. Fourteen women (5% overall) experienced mild vasovagal reactions, with one case of infection and no reports of anaphylaxis or allergy. There were 141 conceptions reported (51%) within six months after Lipiodol flush, and an ongoing pregnancy in 43% (119) of women. For women with ongoing pregnancies, 55% (78/119) conceived spontaneously, and 45% (63/119) via artificial reproductive technology. Mean recalled pain score was 5.7 (SD 3.2; range 0-10) at a single site.

CONCLUSIONS

This Phase 1 study has indicated that Lipiodol flush using HyCoSy may be a safe and efficacious alternative to hysterosalpingography in the workup for infertility. The low adverse effect profile observed in this study coupled with a substantial ongoing pregnancy rate indicates that further investigation of Lipiodol under HyCoSy is warranted.

Treatment effect of oil-based contrast is related to experienced pain at HSG: a post-hoc analysis of the randomised H2Oil study

STUDY QUESTION

Does pain or volume of used contrast medium impact the effectiveness of oil-based contrast during hysterosalpingography (HSG)?

SUMMARY ANSWER

In women who report moderate to severe pain during HSG, the use of oil-based contrast resulted in more ongoing pregnancies compared to the use of water-based contrast, whereas in women who reported mild or no pain, no difference in ongoing pregnancies was found.

WHAT IS KNOWN ALREADY

We recently showed that in infertile women undergoing HSG, the use of oil-based contrast results in more ongoing pregnancies within 6 months as compared to the use of water-based contrast. However, the underlying mechanism of this fertility-enhancing effect remains unclear.

STUDY DESIGN, SIZE, DURATION

We performed a post-hoc analysis of the H2Oil study, a multicentre randomised controlled trial (RCT) evaluating the therapeutic effect of oil- and water-based contrast at HSG. Here, we evaluated the impact of pain experienced at HSG and volume of used contrast media during HSG on ongoing pregnancy.

PARTICIPANTS/MATERIALS, SETTING, METHODS

In a subset of 400 participating women, pain during HSG by means of the Visual Analogue Scale (VAS) (range: 0.0–10.0 cm) was reported, while in 512 women, we registered the volume of used contrast (in millilitres). We used logistic regression analyses to assess whether pain and volume of used contrast media modified the effect of oil-based contrast on ongoing pregnancy rates. Data were analysed according to intention-to-treat principle.

MAIN RESULTS AND THE ROLE OF CHANCE

In 400 women in whom pain scores were reported, the overall median pain score was 5.0 (Interquartile range (IQR) 3.0–6.8) (oil group (n = 199) 4.8 (IQR 3.0–6.4); water group (n = 201) 5.0 (IQR 3.0–6.7); P-value 0.28). There was a significant interaction between pain (VAS ≤5 versus VAS ≥6) and the primary outcome ongoing pregnancy (P-value 0.047). In women experiencing pain (VAS ≥6), HSG with oil-based contrast resulted in better 6-month ongoing pregnancy rates compared to HSG with water-based contrast (49.4% versus 29.6%; RR 1.7; 95% CI, 1.1–2.5), while in women with a pain score ≤5, 6-month ongoing pregnancy rates were not significantly different between the use of oil- (28.8%) versus water-based contrast (29.2%) (RR 0.99; 95% CI, 0.66–1.5). In the 512 women in whom we recorded contrast, median volume was 9.0 ml (IQR 5.7–15.0) in the oil group versus 8.0 ml (IQR 5.9–13.0) in the water group, respectively (P-value 0.72). Volume of used contrast was not found to modify the effect of oil-based contrast on ongoing pregnancy (P-value for interaction 0.23).

LIMITATIONS, REASONS FOR CAUTION

This was a post-hoc analysis that should be considered as hypothesis generating. The RCT was restricted to infertile ovulatory women, younger than 39 years of age and with a low risk for tubal pathology. Therefore, our results should not be generalised to infertile women who do not share these features.

WIDER IMPLICATIONS OF THE FINDINGS

The underlying mechanism of the fertility-enhancing effect induced by HSG with the use of oil-based contrast remains unclear. However, these findings suggest a possible mechanistic pathway, that is increasing intrauterine pressure occurring prior to dislodging pregnancy hindering debris or mucus plugs from the proximal part of otherwise normal fallopian tubes. This information might help in the search of the underlying fertility-enhancing mechanism found by using oil-based contrast during HSG.

STUDY FUNDING/COMPETING INTEREST(S)

The original H2Oil RCT was an investigator-initiated study that was funded by the two academic institutions (AMC and VUmc) of the Amsterdam UMC. The funders had no role in study design, collection, analysis and interpretation of the data. K.D. reports consultancy for Guerbet. H.V. reports consultancy fees from Ferring. C.B.L. reports speakers’ fees from Ferring and research grants from Ferring, Merck and Guerbet. V.M. reports receiving travel and speakers fees as well as research grants from Guerbet. B.W.M. is supported by an NHMRC Practitioner Fellowship (GNT1082548). B.W.M. reports consultancy for ObsEva, Merck KGaA and Guerbet and travel and research grants from Merck KGaA and Guerbet. The other authors do not report conflict of interests.

TRIAL REGISTRATION NUMBER

The H2Oil study was registered at the Netherlands Trial Registry (NTR 3270).

TRIAL REGISTRATION DATE

1 February 2012.

DATE OF FIRST PATIENT’S ENROLMENT

3 February 2012.

How long does the fertility-enhancing effect of hysterosalpingography with oil-based contrast last?

RESEARCH QUESTION

Does the fertility-enhancing effect of tubal flushing during hysterosalpingography (HSG) with oil-based contrast change over time?

DESIGN

This was a secondary analysis of the H2Oil (long-term follow-up) study, a multicentre randomized controlled trial evaluating the effectiveness of oil-based and water-based contrast during HSG. The main outcome was ongoing pregnancy. Cox proportional hazards models for time to ongoing pregnancy were fitted over 3 years of follow-up.

RESULTS

Data on 1107 couples were available; 550 couples had oil-based contrast and 557 water-based contrast at HSG. Ongoing pregnancy rates after 3 years were 77% and 71%, respectively. Median follow-up was 9-10 months (5th-95th percentile: <1 to 36). The hazard ratio for ongoing pregnancy for oil versus water over 3 years of follow-up was 1.26 (95% confidence interval [CI] 1.10-1.45). The scaled Schoenfeld residual plots showed a decrease in hazard ratio that was linear with log-transformed time. After including an interaction with log-transformed time, the hazard ratio immediately after HSG was 1.71 (95% CI 1.27-2.31) and reduced to no effect (hazard ratio of 1) at approximately 2 years. There was no evidence for a change in hazard ratio over time in a subgroup of women who experienced pain during HSG.

CONCLUSIONS

The hazard ratio for ongoing pregnancy of oil-based versus water-based contrast was 1.71 immediately after HSG, gradually decreasing and plateauing towards a hazard ratio of 1 (indicating no effect) after approximately 2 years. This supports the hypothesis that oil-based contrast might dislodge debris or mucus plugs from the Fallopian tubes, but this has yet to be definitively proved.

The use of oil-soluble contrast media for tubal flushing in infertility: A consensus statement from ACCEPT (Australasian CREI Consensus Expert Panel on Trial evidence)

Good evidence that oil-soluble contrast media (OSCM) enhances pregnancy rates when used to assess fallopian tube patency by hysterosalpingogram has prompted rapid clinical uptake by some fertility doctors and imaging specialists in Australia and New Zealand. The ACCEPT group met in July 2019 to develop a consensus document outlining the indications for and safe use of OSCM, to inform and guide clinicians interested in offering procedures using this media to couples with infertility.

Network meta-analyses in reproductive medicine: challenges and opportunities

Network meta-analysis allows researchers to synthesise both direct and indirect evidence, thus enabling simultaneous comparisons of multiple treatments. A relatively recent addition to evidence synthesis in reproductive medicine, this approach has become increasingly popular. Yet, the underlying assumptions of network meta-analyses, which drive the validity of their findings, have been frequently ignored. In this article, we discuss the strengths and limitations of network meta-analyses. In addition, we present an overview of published network meta-analyses in reproductive medicine, summarize their challenges and provide insights into future research opportunities.

Tubal flushing with oil-based or water-based contrast at hysterosalpingography for infertility: long-term reproductive outcomes of a randomized trial

OBJECTIVE

To determine the impact of oil-based versus water-based contrast on pregnancy and live birth rates ≤5 years after hysterosalpingography (HSG) in infertile women.

DESIGN

A 5-year follow-up study of a multicenter randomized trial.

SETTING

Hospitals.

PATIENT(S)

Infertile women with an ovulatory cycle, 18-39 years of age, and having a low risk of tubal pathology.

INTERVENTION(S)

Use of oil-based versus water-based contrast during HSG.

MAIN OUTCOME MEASURE(S)

Ongoing pregnancy, live births, time to ongoing pregnancy, second ongoing pregnancy.

RESULT(S)

A total of 1,119 women were randomly assigned to HSG with oil-based contrast (n = 557) or water-based contrast (n = 562). After 5 years, 444 of 555 women in the oil group (80.0%) and 419 of 559 women in the water group (75.0%) had an ongoing pregnancy (relative risk [RR] 1.07; 95% confidence interval [CI] 1.00-1.14), and 415 of 555 women in the oil group (74.8%) and 376 of 559 women in the water group (67.3%) had live births (RR 1.11; 95% CI 1.03-1.20). In the oil group, 228 pregnancies (41.1%) were conceived naturally versus 194 (34.7%) pregnancies in the water group (RR 1.18; 95% CI 1.02-1.38). The time to ongoing pregnancy was significantly shorter in the oil group versus the water group (10.0 vs. 13.7 months; hazard ratio, 1.25; 95% CI 1.09-1.43). No difference was found in the occurrence of a second ongoing pregnancy.

CONCLUSION(S)

During a 5-year time frame, ongoing pregnancy and live birth rates are higher after tubal flushing with oil-based contrast during HSG compared with water-based contrast. More pregnancies are naturally conceived and time to ongoing pregnancy is shorter after HSG with oil-based contrast.

CLINICAL TRIAL REGISTRATION NUMBER

Netherlands Trial Register (NTR) 3270 and NTR6577(www.trialregister.nl).

Lipiodol visibility under ultrasound

BACKGROUND

Lipiodol is an oil-based solution commonly used in hysterosalpingogram (HSG), but not hysterosalpingo contrast sonography (HyCoSy). In women with unexplained infertility, evidence suggests that tubal flushing with Lipiodol results in improved fertility post-procedure. We propose that Lipiodol can be visualised under ultrasound similar to commonly used saline, and hence utilised for HyCoSy, allowing the benefit of an oil-based tubal flushing to occur with HyCoSy.

AIMS

To examine whether Lipiodol is visible sonographically, assess optimal agitated Lipiodol mix and ultrasound settings for visibility, and compare visibility to agitated saline, routinely used for HyCoSy.

MATERIALS AND METHODS

Two separate sonographers with identical ultrasound machines and model pelvises recorded images with varying degrees of agitated Lipiodol and ultrasound settings, in addition to capturing images with no fluid and agitated saline. Each test was performed in quadruplicate and in random order. Images were read by 47 blinded reporters and visibility reported on a scale of one (not visible) to five (clearly visible).

RESULTS

The mean visibility score for images captured where the Lipiodol sample was agitated five times prior to injection to allow the formation of air microbubbles, regardless of ultrasound setting, were higher than or not different from that for agitated saline (all P > 0.7 when not different, <0.001 when higher).

CONCLUSIONS

Sonographic visualisation of agitated Lipiodol is similar or better than that of agitated saline. Lipiodol may therefore present a possibility for use with HyCoSy, with the added benefit of oil-based tubal flushing, avoiding the radiation exposure of HSG and concurrently providing pelvic soft-tissue evaluation.

Complications after hysterosalpingography with oil- or water-based contrast: results of a nationwide survey

STUDY QUESTION

What is the incidence of complications after hysterosalpingography (HSG) using oil-based contrast versus water-based contrast?

SUMMARY ANSWER

Among 5165 women undergoing HSG, the most frequently reported complication after HSG with oil- and water-based contrast was intravasation of contrast medium (4.8% versus 1.3%, respectively), which was without further consequences, and pulmonary embolization or death did not occur.

WHAT IS KNOWN ALREADY

An HSG with oil-based contrast increases pregnancy rates in women with unexplained infertility. However, there have been some concerns regarding complications, including the risks of intravasation of the contrast medium, oil embolism and infection. Here, we present the incidence of complications after HSG with different types of contrast media used in the Netherlands in the year 2017.

STUDY DESIGN SIZE DURATION

In January 2018, an electronic survey was sent to all 73 clinics in the Netherlands that perform HSG. The survey consisted of 12 questions addressing the number of HSGs performed in 2017, the amount and type of contrast medium used, the occurrence of post-procedural complications and what their clinical consequences were. Non-responding clinics were sent multiple reminders.

PARTICIPANTS/MATERIALS SETTING METHODS

We calculated the incidence of the complications and reported on their clinical consequences. Furthermore, we examined the average amount of contrast used as well as the administration of prophylactic antibiotics.

MAIN RESULTS AND THE ROLE OF CHANCE

The response rate was 96% (67/70) (during the study, one site closed and was not included while two clinics no longer performed HSGs). In the 67 clinics, 3289 HSGs with oil-based contrast and 1876 HSGs with water-based contrast were performed in 2017. The median amount of contrast used was 8.0 ml (interquartile range (IQR) 7.0-10.0) for oil-based contrast and 10.0 ml for water-based contrast (IQR 10.0-10.0). Antibiotic prophylaxis was administered in 61% (41/67) of the clinics. Intravasation occurred in 4.8% of the HSGs performed with oil-based contrast and in 1.3% of the HSGs with water-based contrast (relative risk (RR), 3.6; CI, 2.4-5.4). Pulmonary embolism or death was not reported. Pelvic inflammatory disease (PID) occurred in 0.3% of the HSGs performed with oil-based contrast versus 0.4% with water-based contrast. PID occurred in 0.3% of the HSGs in clinics using antibiotic prophylaxis and 0.2% in clinics not using antibiotic prophylaxis. Allergic reactions were reported in one HSG performed with oil-based contrast (0.03%) compared with two HSGs performed with water-based contrast (0.1%). Anaphylactic reactions did not occur. The overall complication rate was 5.1% in the clinics that used oil-based contrast versus 1.8% in the clinics that used water-based contrast (RR, 2.8; CI, 1.9-4.0; P-value, <0.0001).

LIMITATIONS REASONS FOR CAUTION

Half of the clinics did not routinely register complications, and the incidence of the complications in their clinic was based on the recall of the clinician. Estimated complication rates in the clinics with and without systematic registration did not significantly differ. The survey asked about the frequency of intravasation but no classification system is being used in daily practice, which may create differences in reporting. There was no standard screening of post-HSG thyroid function for the mother and the foetus.

WIDER IMPLICATIONS OF THE FINDINGS

In this nationwide cohort study, the complication rates after HSG were low. Intravasation occurred more frequently with the use of oil-based contrast compared with water-based contrast but did not lead to any problems or symptoms in any of the women. We therefore conclude that safety concerns should not be a reason to deny the use of oil-based contrast in women with unexplained infertility. The data also support that fluoroscopy appears to be an essential safety measure during HSG.

STUDY FUNDING/COMPETING INTERESTS

This work was partly funded by Guerbet, France. I.R. reports receiving travel fee for presenting at the Congress of the American Society for Reproductive Medicine 2019 from Guerbet. V.M. reports receiving travel and speaker's fee as well as research grants from Guerbet. K.D. reports receiving travel and speaker's fee from Guerbet. B.W.M. is supported by an National Health and Medical Research Council (NHMRC) Practitioner Fellowship (GNT1082548). B.W.M. reports consultancy for ObsEva, Merck KGaA and Guerbet and travel and research grants from Merck KGaA and Guerbet. The other authors do not report conflicts of interest.

TRIAL REGISTRATION NUMBER

N19.056.