Non-invasive Test to Detect Intra-amniotic Infection in Women With Preterm Labor and Intact Amniotic Membranes (IAI)

Intra-amniotic infection (IAI) is an acute bacterial infection of the amniotic fluid and intrauterine contents during pregnancy and occurs in 4% to 10% of all deliveries (Newton, ER., 1993. Newton, ER, et al., 1989. Soper, DE, et al., 1989). IAI is an important cause of maternal and neonatal morbidity. Identifying and appropriately treating women with IAI is, therefore, a major obstetrical challenge.

Intrauterine infection may occur early in pregnancy and remain undetected for a prolonged period, thus exposing the fetus to the effects of infection/inflammation for a considerable period. Ideally, an early diagnosis of IAI is important to allow timely treatment and intervention. Unfortunately, the early diagnosis is difficult because the clinical signs and symptoms of IAI may occur late in the course of the infection and are neither sensitive nor specific. Therefore, to avoid a delay in diagnosis a high degree of suspicion and the appropriate use of adjunctive laboratory tests are warranted.

Inclusion Criteria:

• Subject is greater than or equal to 18 years of age
• Subject has singleton gestation
• Subject has fetus with gestational age greater than or equal to 22 0/7 weeks and less than or equal to 36 6/7 weeks
• Subject has documented intact amniotic membranes
• Subject's care provider plans to or has performed an amniocentesis procedure

• Subject has had evidence of spontaneous preterm labor as evidenced by documented regular uterine contractions (greater than or equal to four per hour, or if less than 26 weeks gestation, cramping or backache) and one or more of the following:

  1. Progressive cervical change with cervical dilation of greater than or equal to 2 cm
  2. Effacement of greater than or equal to 50%
  3. Cervical length of less than or equal to 30 mm via transvaginal ultrasound
  4. Positive fetal fibronectin test

Exclusion Criteria:

• Subject has documented ruptured amniotic membranes
• Subject has fetus with major fetal anomaly or chromosomal aneuploidy
• Subject has medical indication for preterm birth (e.g. pre-eclampsia)
• Subject is unable to provide written informed consent