Diagnosis and Management of Intraamniotic Infection

Intraamniotic infection(IAI)or chorioamnionitis is a common cause of preterm birth and may cause adverse neonatal outcomes,including neonatal pneumonia,respiratory distress,meningitis,sepsis,and death.Maternal morbidities from intraamniotic infection include dysfunctional labor requiring increased intervention,cesarean birth,postpartum uterine atony with hemorrhage,endometritis,peritonitis,sepsis,adult respiratory distress syndrome and,rarely,death.Chorioamnionitis can result from an ascending infection,iatrogenic causes or transplacental passage from maternal blood-borne infections.The clinical findings of chorioamnionitis include maternal fever(≥38°C),maternal(>100 beats per minute)and/or fetal tachycardia(>160 beats per minute),maternal leukocytosis on complete blood count(>15000 cells/mm 3),and uterine tenderness and/or purulent and/or foul-smelling amniotic fluid.The management of chorioamnionitis mainly includes antibiotic therapy and delivery.Women with previable preterm premature rupture of membranes should be offered realistic counseling from a multidisciplinary approach.The separation of the mother and the fetus to preserve the life of the mother should prioritize delivery methods that result in a living fetus if possible,with appropriate neonatal resuscitation available.

Is Induction of Labor with Early Rupture of Membranes Associated with an Increased Rate of Clinical Chorioamnionitis?

Objective: The objective of this study was to determine if early rupture of membranes (ROM) in women undergoing induction of labor (IOL) at term is associated with an increased rate of clinical chorioamnionitis. Study Design: A retrospective cohort study was performed on women undergoing IOL. Early ROM was defined as ROM at a modified Bishop score less than 5, cervical dilation less than 4 cm, or cervical effacement less than 80%. The rate of clinical chorioamnionitis was compared between women with early and late ROM. Results: The rate of clinical chorioamnionitis was 8.6% (24/279). ROM at an effacement of less than 80% was associated with a rate of clinical chorioamnionitis of 15.4% (12/78) compared to 6.0% (12/201) at an effacement of equal to or greater than 80%, p = 0.017. The rate of cesarean delivery was higher for patients with early ROM by any definition: 32% compared to 17.5% by modified Bishop score (p = 0.031), 32.4% versus 18.2% by cervical dilation (p = 0.049), and 33.3% versus 14.9% by cervical effacement (p = 0.001). Conclusions: In patients undergoing IOL, early ROM may be associated with an increased rate of clinical chorioamnionitis when performed at a cervical effacement of less than 80% and an increased rate of cesarean delivery.

Amniocentesis: A contemporary review

Amniocentesis is an essential tool in obstetrics. Invasive testing remains the only modality for diagnostic genetic testing and the only way to provide comprehensive test-ing for chromosomal abnormalities. Despite increasing use of cell free fetal deoxyribonucleic acid （DNA） testing, amniocentesis should still be offered to all women who desire more complete and accurate genetic testing. Counseling patients on the limitations of screening tests is of the upmost importance and amniocentesis should continue to be recommended to confrm positive results from cell free fetal DNA testing or in the case of failed cell free fetal DNA test. As cell free fetal DNA screening has not adequately been studied in multiple gestations, its use is not recommended in this population and invasive testing should be offered. Amniocentesis is also very useful in providing additional information in settings other than genetic testing the second and third trimester. If intraamniotic infection is suspected, but the clinical fndings are not enough to guide manage-ment, amniocentesis can provide testing that can both immediately clarify the picture （interleukin-6, gram stain, glucose levels） and finally confirm the presence of infection （culture）. It can also be used to detect the presence of intrauterine viral infections. Additionally, amniocentesis may be used to test for markers of fetal lung maturity. The American Congress of Obstetricians and Gynecologists recommends that amniocentesis for this indication not be used in cases where late preterm delivery is indicated. It may be useful in guiding decision-making, however , when late preterm delivery is indicated, but when exact timing is unclear. Regardless of the indication, amniocentesis appears to be a relatively low risk procedure with minimal risk to the patient. Additional randomized controlled trials are not likely, as they are not feasible to due extremely high number of participants that would be needed to detect a difference in loss rates. Based on current literature, however, the risk of pregnancy loss from second trime-ster amniocentesis is low in both singleton and twin gestations. We counsel patients that technique has changed since the original studies in the 1970s and feel comfortable quoting a loss rate of 1/500-1/1000 based on contemporary data.