Influence of HyCoSy on spontaneous pregnancy: a randomized controlled trial.

BACKGROUND

The aim of the study was to test whether the use of sonography contrast could enhance the chance of spontaneous clinical pregnancy in women undergoing subfertility investigation.

METHODS

Couples with at least 1 year of infertility who were scheduled for a consultation including a hysterosalpingo contrast sonography (HyCoSy) were invited to participate in the study. We compared flushing with water-soluble contrast medium (WSCM) versus no flushing. Randomization sequence was computer generated, stratified for age and group allocation was concealed. Primary outcome was clinical pregnancy defined as a sonographically visible fetal sac, detected within 6 months from randomization. Secondary outcomes were spontaneous miscarriage and birth. Exclusion criteria were female age >or=40 years, severe male infertility, previously known severe tubal infertility and suspected anovulation.

RESULTS

The mean age of the study population (n = 334) was 31.9 years. Duration of infertility was 2.1 years. The clinical pregnancy rate was 29.2% in the HyCoSy group and 26.5% in the non-flushing group, the difference being 2.7% (95% confidence interval -6.9 to 12.3%, P = 0.63).

CONCLUSION

The clinical impression of an enhanced pregnancy rate after performing HyCoSy could not be confirmed. Tubal investigation with sonography using water-soluble contrast has a function as a diagnostic procedure but not in terms of increasing pregnancy rates in subfertile patients.

TRIAL REGISTRATION NUMBER: ISRCTN20715945.