The study was terminated because it is very difficult to recruit more patients.

· What we know: Hydrosalpinx and IVF About 40% of patients undergoing IVF have tubal disease and in 25%-30% of tubal disease patients there is fluid collection within the tube; hydrosalpinx. The amount of fluid in the hydrosalpinx is known to increase with ovarian stimulation (as in IVF) and often empties into the uterine cavity. Fluid from hydrosalpinges has been found to be detrimental to the growth and development of mouse embryos in vitro, and associated with reduced levels of endometrial integrins in vivo. This could be the explanation of the reduced pregnancy rates after IVF in patients with tubal disease and hydrosalpinx compared with those with tubal disease but no hydrosalpinx. This effect was evidence in both fresh and frozen embryo transfer cycles. Also there was a significant increase in miscarriage in association with hydrosalpinx.

The study aims to answer the question: does ultrasound-guided aspiration of ultrasound diagnosed hydrosalpinx at the time of egg collection improve the pregnancy rate in IVF?

· What we do not know: Treatment of hydrosalpinx and IVF Several studies in the literature have suggested that the treatment of hydrosalpinx pre-IVF would improve the pregnancy rate to a level similar to tubal disease patients without hydrosalpinx. The treatment modalities explored were salpingectomy, salpingostomy, tubal occlusion and ultrasound-guided aspiration either one month before or at the time of egg collection. All studies reported to date have been retrospective and with poor control design. A prospective randomised controlled trial is needed. All modalities have been associated with a similar improvement in pregnancy rate, but the least invasive modality is ultrasound-guided aspiration at the time of oocyte collection. We propose to conduct a prospective randomised controlled trial to evaluate the effect of ultrasound-guided aspiration (versus no aspiration) of hydrosalpinx at the time of egg collection on the pregnancy rate in IVF.

Inclusion Criteria:

• healthy women, ASA class 1 (normal healthy) or class 2 (with mild systemic disease);
• undergoing IVF or ICSI and reaching the stage of egg collection;
• with ultrasonically diagnosed hydrosalpinx and identifiable during the phase of ovarian stimulation;
• giving written informed consent.

Exclusion Criteria:

• patients not giving written informed consent;
• patients cancelled for poor ovarian response;
• ultrasonically diagnosed hydrosalpinx and identifiable for the first time at egg-collection