The data presented in the current study revealed that salpingectomy is more effective than extended doxycycline treatment during IVF-ET cycle in improving the outcomes of IVF-ET in patients with hydrosalpinx undergoing IVF-ET.
The results of the current study indicate that the extended doxycycline treatment is not effective in minimizing the detrimental effect of hydrosalpinx on the outcomes of IVF-ET. In contrast to our findings, a retrospective study comparing the reproductive outcomes of IVF-ET cycles of 17 patients with hydrosalpinx treated with extended doxycycline treatment with the reproductive outcomes of IVF-ET cycles of 25 patients with adhesions/proximal tubal occlusion, and 22 patients with endometriosis/unexplained infertility revealed that the implantation and live birth rates were comparable between the three groups. The authors suggested that antibiotic treatment could prevent the detrimental impact of hydrosalpinx on the outcomes of IVF-ET [10].
In the current study, no pregnancies occurred in seven patients in the doxycycline group who have uterine fluid collection on the day embryo transfer. The results of our study are in agreement with several studies which revealed that the patients with hydrosalpinx and uterine fluid collection on the day embryo transfer have almost no chance of pregnancy if embryos are transferred [11–13].
Several theories have been proposed to explain the association between hydrosalpinx and poor outcomes of IVF-ET. Several authors proposed that the leakage of hydrosalpingeal fluid into the uterine cavity may exert an embryotoxic effect, alter endometrial receptivity or mechanically wash the embryos [14–16].
Although the majority of studies documented the toxicity of hydrosalpingeal fluid on mouse embryos [14], several studies revealed that the hydrosalpingeal fluid has no adverse effect on human embryos development [15–16].
One theory suggested that the inflammation of the hydrosalpinx (caused by Chlamydia trachomatis or other bacteria) is the main cause of the detrimental effect of hydrosalpinx on the outcomes of IVF-ET. Consequently, antibiotics (particularly those effective against Chlamydia trachomatis) were used to prevent this detrimental effect [10].
Several authors suggested that cytokines, prostaglandins, leukotrienes and reactive oxygen species produced by chronic inflammatory cells associated with hydrosalpinx could have an embryotoxic effect [17–18]. Moreover, simultaneous acute salpingitis and acute endometritis often occur in patients with acute pelvic inflammatory disease, puerperal sepsis or post abortion infections. Hydrosalpinx and chronic endometritis are common sequels of acute salpingitis and acute endometritis respectively [19]. Several studies revealed that chronic endometritis can cause recurrent implantation failure and that antibiotic treatment of chronic endometritis could improve the uterine receptivity [20–21].
Several studies revealed that the expression of markers of endometrial receptivity (alpha vbeta3 and leukaemia inhibitory factor) was significantly decreased at the time of the implantation window in patients with hydrosalpinx and that the expression of these markers was significantly increased after salpingectomy [22–23]. The results of these studies explained the mechanism by which hydrosalpinx exerts its detrimental effect on the outcomes of IVF-ET and confirmed that salpingectomy can prevent this effect.
The main limitations of the current study are the retrospective design and the small sample size. However, to the best of our knowledge the current study is the largest study which evaluated the effect of extended doxycycline treatment before and after oocyte retrieval on the outcomes of IVF-ET cycles in patients with hydrosalpinx. Moreover, the current study is the first study which compared salpingectomy with extended doxycycline treatment before and after oocyte retrieval in the management of patients with hydrosalpinx undergoing IVF-ET.