The recent study from Dreyer et al examining the chance of natural pregnancy following hysterosalpingography (HSG) has provoked a significant amount of interest in the lay press, with suggestions that this well established diagnostic fertility test could be offered therapeutically and be considered as an alternative to IVF. But it is false and here’s why.
Performing an HSG is a quick, outpatient procedure, which appears to be safe and relatively inexpensive. Women experiencing subfertility are often given tests to establish whether the fallopian tubes are clear, of which HSG is one of the most longstanding and popular. The procedure consists of flushing liquid contrast media through the tubes and taking repeat x-rays to delineate tubal anatomy and identify any blockages. Various liquid agents have been used for an HSG, including water-soluble contrast media and oil-soluble contrast media.
Clinicians have often noted that many women conceive shortly after tubal flushing, which has raised the question whether it could also be used as a treatment for subfertility. In the 1950s it was first reported that women who received HSG with oil based media showed double the pregnancy rates of women who received no procedure. Many reports on the therapeutic aspect of oil-soluble contrast media have since been published, most of these reports, however, did not have satisfactory control groups. There has also been debate about which contrast medium should be used (water-soluble or oil-soluble media) and their influence on pregnancy rates.
Although many studies have shown a possible fertility-enhancing effect of HSG with the use of oil-based contrast, only three randomised, controlled trials have been published between 2002 and 2009. When the data from these trials were combined, the results showed that the odds of ongoing pregnancy after HSG performed with oil contrast were three times higher compared with no intervention.
In the newest study – the H2Oil trial – which was published in a leading medical journal, the New England Journal of Medicine, participants were recruited from 27 hospitals in the Netherlands. Women were eligible to participate in the trial if they were less than 39 years of age and had been trying to conceive for at least one year. Importantly, women with known endocrine disorders (eg polycystic ovary syndrome, diabetes, thyroid disorders), a history of pelvic inflammatory disease, previous chlamydia infection, or known endometriosis were excluded from the study. In addition patients were excluded if the male partner had impaired sperm.
Among the women included, 557 were randomly assigned to HSG with the use of oil contrast and 562 were assigned to HSG with the use of water contrast. Six months later, the ongoing pregnancy rate was assessed for all the women. The researchers found the rate was significantly higher after using oil contrast compared with water contrast.
In particular the authors reported a 38 percent live birth rate after oil-based contrast HSG compared to 28 percent after water-based contrast HSG. About three-quarters of the women who conceived did so spontaneously while the remaining one quarter underwent fertility treatment, mostly intrauterine insemination.
This multicentre study included a large number of patients and was well-designed. There may be a number of theories behind the results, which highlight the potential therapeutic role of HSG.
However, it should be pointed out that the aim of this study was not to compare HSG with IVF. In addition, women with identified causes of infertility, such as endometriosis, polycystic ovarian syndrome, or endocrine abnormalities, or couples with male factor infertility, were not included in the study. These patients still constitute the majority of the women and couples seen in fertility clinics.
In conclusion, HSG should only be considered after a careful selection process, which should take into account the individual circumstances, wishes and diagnoses of the women and couples seeking fertility treatment. So before opting for HSG in your local centers have a proper talk with your doctors and determine whether it is for you or not. Our BioTexCom specialists will be willing to help you to get pregnant via the wide range of procedures and treatment we provide (see – http://biotexcom.com/services/).