Pregnancy Outcomes Following Preconception Treatment of Asymptomatic Bacterial Vaginosis in an Infertility Population: A Prospective, Randomized, Double-Blind, Placebo-Controlled Trial.

The purpose of this study is to determine if preconception treatment of asymptomatic bacterial vaginosis improves pregnancy outcomes (i.e. biochemical pregnancy rate). Study protocol as follows:

1. Patients will be notified of study via face-to-face contact at the initial clinic visit (baseline ultrasound visit, menstrual cycle day 2-5), by physician referral or the Stanford website. Patients expressing interest will be screened in person to confirm that they meet all enrollment criteria. The participant will be asked to sign informed consent documents and a brief intake questionnaire with then be administered.
2. Enrolled patients will then be screened for bacterial vaginosis at their next visit (typically on menstrual cycle day 12), prior to transvaginal ultrasound. The screening will require that a speculum be inserted into the vagina and a vaginal smear be collected with a swab from the posterior fornix. A microscopic slide will be prepared by rolling the swab on the surface of a glass slide. The diagnosis of bacterial vaginosis will be established clinically using the Amsel criteria to confirm 3 of the following 4 signs: clue cells; vaginal pH ≥4.5; fishy odor before or after the addition of 10% potassium hydroxide solution to a wet-mount side; and a homogeneous, off-white, discharge. For validation of clinical diagnosis, 100% of screen positive slides, and 10% of screen negative slides, will be sent for to the Department of Pathology for Gram staining.
3. The patients with a positive screen for bacterial vaginosis will then be randomized to receive metronidazole 500mg orally twice daily for seven days (treatment arm) or placebo orally twice daily for seven days(control arm). Randomization will be performed using a computer-generated code. Those patients whose screen is negative will also be followed for outcomes, but no randomization will be performed.
4. All randomized patients will continue with routine monitoring and insemination as planned by their treating physician.
5. If pregnancy is confirmed at least 12 weeks after intrauterine insemination by ultrasound evidence of a fetus with heartbeat, information will then be collected regarding the pregnancy and its outcome.
6. Primary and secondary outcomes will be followed for 2 years after date of enrollment for all patients.