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?

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.

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.

The SELFI Study: Iodine Excess and Thyroid Dysfunction in Women Undergoing Oil-Soluble Contrast Hysterosalpingography

CONTEXT

Hysterosalpingography (HSG) with oil-soluble contrast medium (OSCM) improves pregnancy rates. However, OSCM has high iodine content and long half-life, leading to potential iodine excess.

OBJECTIVE

This work aimed to determine the pattern of iodine excess after OSCM HSG and the effect on thyroid function.

METHODS

A prospective cohort study was conducted of 196 consecutive consenting eligible women without overt hypothyroidism or hyperthyroidism. All completed the study with compliance greater than 95%. Participants underwent OSCM HSG (Auckland, 2019-2021) with serial monitoring of thyrotropin (TSH), free thyroxine (FT4), and urine iodine concentration (UIC) for 24 weeks. The main outcome measure was the development of subclinical hypothyroidism (SCH), defined as a nonpregnant TSH greater than 4 mIU/L with normal FT4 (11-22 pmol/L) in those with normal baseline thyroid function.

RESULTS

Iodine excess (UIC ≥ 300 μg/L) was almost universal (98%) with UIC peaking usually by 4 weeks. There was marked iodine excess, with 90% and 17% of participants having UIC greater than or equal to 1000 μg/L and greater than 10 000 μg/L, respectively. Iodine excess was prolonged with 67% having a UIC greater than or equal to 1000 μg/L for at least 3 months. SCH developed in 38%; the majority (96%) were mild (TSH 4-10 mIU/L) and most developed SCH by week 4 (75%). Three participants met the current treatment guidelines (TSH > 10 mIU/L). Thyroxine treatment of mild SCH tended to improve pregnancy success (P = .063). Hyperthyroidism (TSH < 0.3 mIU/L) occurred in 9 participants (5%).

CONCLUSION

OSCM HSG resulted in marked and prolonged iodine excess. SCH occurred frequently with late-onset hyperthyroidism occasionally. Regular thyroid function tests are required for 6 months following this procedure.

Immunology and Immunotherapy of Endometriosis

Endometriosis is one of the most common gynecological and systemic diseases, with a remarkable immune background. Patients suffer from pain and fertility reduction. Due to the distinct immune component, an immunotherapeutic approach may gain importance in the future. In endometriosis, shifts in the cell fractions of the immune system are well known. Moreover, hypoxia concomitant with inflammation causes a disturbed immune response. The removal of endometriosis has a therapeutic effect, normalizes the immune disorders, and remains the most effective causative treatment in terms of pain and infertility. A key issue is whether a similar effect can be achieved for fertility with non-invasive immunotherapy where surgery is inadvisable or cannot be performed for various reasons. Numerous immunotherapy trials, including vaccines, were conducted on animals only, although the research is encouraging. Among the promising methods of non-specific immunotherapy is the administration of an ethiodized oil contrast. Moreover, due to the significant successes of immunotherapy in oncology, the possibility of immunotherapy affecting NK cells has been postulated. NK cells are responsible for the surveillance and apoptosis of ectopic cells. Expanding the arsenal of endometriosis treatment by immunotherapy is promising due to the significant contribution of immunological factors and the limitations of current treatment methods.

The Impact of Preconceptional Hysterosalpingography with Oil-based Contrast on Maternal and Neonatal Iodine Status

The objective of this study is to investigate the impact of preconceptional exposure to oil-based iodinated contrast in the hysterosalpingography (HSG) on pregnant women and their offspring's iodine status, thyroid function, and the outcomes of pregnancy. A cross-sectional evaluation of iodine status was performed on pregnant women with the preconceptional experience of ethiodized-oil HSG. For those found to have iodine excess (with serum iodine concentration (SIC) > 92 μg/L), a prospective follow-up was conducted until termination of the pregnancy or 1 week postpartum. Among 70 of 425 pregnant women with preconceptional ethiodized-oil HSG, iodine excess was initially confirmed in 38 (54.3%), with an elevated SIC (294.00 μg/L [142.00, 123.20]) and urinary iodine-to-creatinine ratio (UI/Cr) (830.00 μg/g Cr [437.50, 255.30]), both higher than the normative data (P = 0.000, P = 0.000). Subsequent follow-up in pregnancy showed a downward trend in both SIC and UI/Cr. Thirty-four women delivered healthy neonates at full term, though the other 4 cases of premature birth, abnormal fetal karyotype, spontaneous abortion, and neonatal cardiac defect were reported. After delivery, the iodine concentration in maternal breast milk and neonatal urine was 584.50 μg/L [328.50, 1507.50] and 424.00 μg/L [277.00, 657.50], respectively, both higher than normative data (P = 0.001, P = 0.015). For thyroid evaluation, 25 cases (65.79%) of clinical or subclinical hypothyroidism and 2 cases (5.26%) of thyrotoxicosis were confirmed in women with iodine excess. Neither goiter nor thyroid dysfunction was detected in any offspring. Preconceptional exposure to oil-based contrast in HSG might exert a far-reaching impact on maternal and offspring iodine status, and tend to result in increased risk of maternal thyroid dysfunction.