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

Objective:
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 aim to compare the fertility-enhancing outcomes and adverse effects of oil and water-based contrasts in patients who underwent HSG.

Material and Methods:
This systematic review and meta-analysis was conducted following the PRISMA guidelines. We searched 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.

Results:
Eleven studies with 4,739 patients were selected. The pregnancy rate in the oil group was significantly higher than the water group (OR=1.51 [1.23, 1.86], P 0.001). Our meta-analysis favored the oil group in abdominal pain and vaginal bleeding with the odd ratio of 0.73 [0.58, 0.91], (P = 0.06) and 0.67 [0.52, 0.86], (P = 0.02), respectively. Water-based contrast was associated with less intravasation (OR= 2.09 ([1.09–4.02], P = 0.03). There are no differences between both 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).

Conclusion:
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 (VAS) pain score.