Treatment strategies for intra-amniotic infection and/or inflammation in preterm labor cases

Spontaneous preterm birth (sPTB) is caused by multiple factors; however, the main cause is intra-amniotic infection and/or inflammation. The frequency of intra-amniotic infection/inflammation is higher in extremely sPTB (<28 weeks) and causes long-term cognitive impairments, such as cerebral palsy and mental retardation. The rate of intra-amniotic superinfections, such as Ureaplasma/Mycoplasma and bacteria, is high in sPTB < 27 weeks of gestation. Obstetrical strategies based on accurate information on intra-amniotic infection/inflammation are needed to prevent sPTB (particularly extremely sPTB) and improve the long-term prognosis of preterm infants. Our PCR method, which is sensitive and free from false positives, accurately identifies whether intra-amniotic infection is present. Appropriate antibiotic therapy against intra-amniotic infection (macrolides against Ureaplasma/Mycoplasma and beta-lactams against bacteria) in preterm labor (PTL) cases effectively prolongs the gestational period by 4 weeks. In contrast, the use of antibiotics shortens the gestational period in cases without intra-amniotic infection. We previously reported that 17-alpha-hydroxyprogesterone caproate (17OHP-C) effectively prolonged pregnancy by 4 weeks in PTL cases with mild intra-amniotic inflammation, but not in those with severe intra-amniotic inflammation. Treatment strategies based on accurate intra-amniotic information is expected to prolong pregnancy. However, obstetrical interventions are limited once severe clinical symptoms appear. In addition to the use of drugs to control uterine contractions, antibiotics and/or 17OHP-C may be necessary in the treatment of PTL cases following the accurate assessment of intrauterine infection and/or inflammation is confirmed.