Preterm labor is frequently caused by IAI

Intraamniotic infection is an acute bacterial infection of the amniotic fluid and intrauterine contents that complicates 4 – 10% of all pregnancies. Intraamniotic infection is also an important cause of preterm birth, responsible for 10 – 20% of all preterm births and more than 50% of preterm births occurring before 30 weeks of gestation.¹

There is increasing awareness of the prevalence of IAI in preterm labor and the importance of early detection. In a pooled analysis of 6 studies since 2000, IAI as defined by positive AF culture, including Mycoplasma, was present in 12.7% of all preterm labor cases.³



Although historically microbial culture of AF has been recognized as the “gold standard” for the detection of IAI more recent clinical research has demonstrated that AF culture alone underestimates the true prevalence of IAI.

The use of AF culture alone as a tool for the diagnosis of IAI has a number of disadvantages: culture depends on growth conditions favorable to a select group of known microorganisms. Consequently, difficult to cultivate or uncultivatable bacteria will not be detected by culture alone. In addition, previous antibiotic therapy can cause AF cultures to yield a false negative test result.

Use of 16S rDNA PCR assay in amniotic fluid detects 31% to 56% more cases of IAI as compared to cases of IAI that are detected by culture alone. Recent published clinical research utilizing AF PCR and culture demonstrate that IAI is likely present in 15% to 18% of all PTL cases.⁴

IAI Is Associated With Increased Risk Of Critical Complications

Intraamniotic infection is a critical complication of pregnancy and is associated with significantly risk of morbidity. The table below summarizes published clinical results demonstrating neonates born in the setting of IAI had a 2.7 times -- 3.4 times higher risk of complications such as neonatal sepsis, respiratory distress syndrome, intraventricular hemorrhage, as compared to a similar group of neonates born outside the setting of IAI, but matched for other variables such as gestational age, birth weight, preterm rupture of membranes, preeclampsia, cesarean birth:



In addition:

• IAI is associated with at least one-third of all early-onset neonatal sepsis and pneumonia in United States.⁶

• IAI also accounts for highest proportion of neonatal deaths in the United States and up to 40% of cases of maternal febrile morbidity in the peripartum period.⁷

• A study published in JAMA demonstrated a clear link between IAI and cerebral palsy via meta-analysis of 19 published studies.⁸

• IAI is also responsible for a disproportionate share of aggregate prenatal healthcare costs (estimated in the United States to be $4 to $6 billion annually).⁹