Organisms in amniotic fluid after genetic amnio. (Pregnancy Outcomes Unaffected).

KEY LARGO, FLA. -- Genetic amniocentesis introduces microorganisms into the amniotic fluid, but there were no differences in pregnancy outcomes in women who underwent the procedure compared to other obstetric patients.

"Despite our sterile technique, we are introducing organisms in these asymptomatic patients coming in for a genetic amino," Dr. Iffath Abbasi Hoskins said at the University of Miami School of Medicine New Concepts in Obstetrics and Gynecology meeting.

A total of 318 pregnant patients between 15 and 23 weeks' gestation were enrolled in the study. They had amniocentesis for the usual indications. Researchers reviewed pregnancy outcomes and also those of a control group of 100 more obstetric patients, Dr. Hoskins explained.

The clinical incidence of intraamniotic infection or chorioamnionitis is small; more cases are identified through histopathologic testing.

Whereas only 5%-8% of cases are seen clinically, histology done at preterm delivery indicates an incidence of 40%-60%, and histology at term shows an incidence of 30%-40%.

"Part of the problem with chorioamnionitis is that it is not all that common, although it may seem common to you if you are on call at night or on the weekends. It is more prevalent in some socioeconomic groups, however," said Dr. Hoskins, executive director of women's services at Memorial Health University Medical Center, Savannah, Ga.

Low socioeconomic status is a risk factor because it correlates with poorer nutrition and possibly fewer antimicrobial factors in the amniotic fluid; the protective factors include phosphate hexapeptides, zinc peptide complexes, and lysozymes. Therefore, adding zinc and phosphorus to amniotic fluid in experiments improved its antimicrobial activity.