Pelvic inflammatory disease is an infrequent complication of ultrasound-guided transvaginal oocyte aspiration, or embryo transfer with a reported incidence of 0.2 to 0.5%. This is mainly due to the fact that in most IVF programs the patients received either prophylactic antibiotic following the procedure.
Signs and symptoms of pelvic inflammatory disease are: pyrexia, abdominal pain and dysuria. However, this does not exclude occult sub-clinical bacterial colonization, which may influence the success of embryo implantation.
Oocyte aspiration can also lead to the development of tubo-ovarian or pelvic abscess, which is a sever complication of the process and might need surgical intervention ending with adnexectomy.
Some ultrasound images of Tubo-ovarian abscess
CT of the pelvic demonstrating Tubo-ovarian abscess
Woman with pelvic inflammatory disease.A, Endovaginal sonography shows an inhomogeneously enlarged right ovary (arrowheads).B and C, Contrast-enhanced CT shows enlargement of the ovaries (B, arrows) with ill-defined contours of the ovaries and uterus, and some free pelvic fluid (C, arrow).
MRI presenting Tubo-ovarian abscess
The diagnosis can also be identified by laparoscopy:
Normal pelvic laparoscopy Direct visualization of the inflammatory pelvic area
Mechanisms of infection
During transvaginal aspiration, accidental needle transport of cervicovaginal flora into ovarian tissue can cause unilateral or bilateral oophoritis, and accidental puncture of a contaminated or sterile hydrosalpinx can cause salpingitis. Some authors have attributed pelvic infection to infected endometriotic cysts or tubo-ovarian abscess after aspiration of endometriomas, or, rarely, to inadvertent puncture of the bowel. Pelvic infection can occur as a direct consequence of transcervical ET. This is evidenced by reported cases of PID following ET in an agonadal donor-egg recipient, or during cryopreserved ET.
Effect of acute pelvic infection on IVF-ET outcome
The appearance of PID at the critical time of implantation may cause a failure to conceive. This finding has several possible explanations, as outlined in detail below.
Endotoxin-releasing bacteria can be introduced into the peritoneal cavity during transvaginal oocyte recovery, and into the uterine cavity or tubes during ET.
Bacteria trigger a chain of events that lead to the activation, proliferation, and differentiation of lymphocytes, and the production of specific antibodies and various cytokines.
Apart from their direct role on implantation and early embryonic development, cytokines may mediate temperature elevation and indirectly affect the outcome of IVF-ET.
The potential for intraperitoneal bacterial contamination led to the routine use of prophylactic antibiotics and vaginal disinfection.
Pelvic inflammatory disease or tubo–ovarian abscess after OPU require accurate diagnosis and prompt treatment with broad-spectrum antibiotics. In the presence of a pelvic abscess that is larger than 8cm or unresponsive to medication, transvaginal or percutaneous drainage is the treatment of choice, with or without ultrasound-guided intracavitary instillation of a combination of antibiotics. Sometimes surgical laparoscopy or laparotomy is needed to evacuate the abscess or remove the infected tubes or adnexae.