Ureaplasma Infection: Its Effect on Fertility and IVF Outcome

Ureaplasma urealyticum is a bacteria that belongs to the mycoplasma family. It can be detected in the reproductive tract of as many as 40% of individuals (male and female). Ureaplasma probably does not prevent normal conception in the majority of cases, because the uterine cavity remains sterile even in women whose cervical mucous cultures positive for the organism. However, when present in the woman's cervical secretions, the organism can be unintentionally dragged into the uterine cavity through introduction of a catheter into the uterus at the time of embryo transfer (ET) or intrauterine insemination (IUI). Molecular biologists have shown that contamination of rapidly growing cell cultures, by this organism and its close “relative", mycoplasma hominis rapidly destroys such cells. The implanting embryo is indeed an example of an organism that comprises rapidly growing cells in a biological culture medium (the uterine lining), and as such, the cells of the trophoblast that form the "root system” of the embryo are vulnerable to intrauterine infection with Ureaplasma. However, even if the uterine cavity were to become infected, the infection willl be purged with the shedding of the infected lining at the time of the next menstruation.

While infection with Ureaplasma rarely produces symptoms in the woman, it sometimes causes symptomatic prostatitis or epydidimitis in men. Although ureaplasma can be transmitted from one partner to the other by sexual intercourse, it may also be acquired by other means, since a large percentage of couples in monogamous relationships will culture positive for the organism. It is very difficult for the organism to grow in the laboratory. Accordingly, the reproductive secretions of both partners should be evaluated (sperm and cervical mucus) individually. Successful culturing of ureaplasma requires a specialized media in which the specimens can be transported safely from the physician’s office to the microbiology laboratory.

If both partners culture negative, we can assume that there is no infection present. However, if one partner cultures positive and the other negative, we would err on the side of caution, by assuming that the negative result was caused by the difficulty in culturing the organism. When ureaplasma is detected in the reproductive secretions of either partner, both should be treated concurrently with the appropriate antibiotic (doxycycline, zithromax, erythromycin, ciprofloxin, or metranidazole).

Unfortunately, in approximately 30-40% of couples infected ureaplasma urealyticum, the bacteria will have built resistance to mainstay traditional antibiotics such as tetracyclines (e.g. doxycycline) and erythromycin (e.g. Zythromax) derivatives. In such cases, ciprofloxin or metronidazole (Flagyl) therapy might be needed. This is the reason that we prefer to document cure by reculturing each partner prior to beginning ovarian stimulation for an IVF cycle.

Several authors have shown a difference in pregnancy rates among patients with ureaplasma infection who were treated with antibiotics and those who were not. Other reports have not been able to identify an effect on outcome from ureaplasma infection. Thus, until the final verdict is in regarding the roll of ureaplasma with regard to its effect on IVF implantation, we prefer to err on the side of caution and ensure that this organism is absent in cervical secretions and semen before transferring embryos. To this end, my patients all receive prophylactic antibiotic therapy around the time of embryo transfer. This is administered as oral ciprofloxin. A day or two prior to embryo transfer, vaginal cleomycin suppositories are added.