Intra-amniotic debris linked to Preterm Birth independent of Cervical Funnel

Amniotic fluid ‘‘sludge’’ (A) with normal cervix (B) with short cervix
courtesy:https://www.researchgate.net/figure

Presence of Intra-amniotic debris or sludge identified by sonography is linked to increased risk of Preterm Birth(PTB) before 34 weeks of pregnancy in nulliparous women with a cervical length less than 30 mm, reports the results of a secondary cohort study accepted for publication in Journal Ultrasound in Obstetrics and Gynecology.

This secondary analysis of multicentric trial was funded by Eunice Kennedy Shriver National Institute of Child Health and Human Development Maternal-Fetal Medicine Units (MFMU) Network.

The exact composition of amniotic fluid debris is not known. They may be formed of hemorrhage, meconium or a mixture of bacteria and inflammatory cells, that is encased in a biofilm that is resistant to antibiotics. They are probably a sign of placental senescence, and preterm delivery seems to be a protective phenomenon to shuttle the fetus out of the already compromised environment.

The initial trial was conducted to study the effect of progesterone injections to prevent preterm birth in nulliparous women with a short cervix.

A total of 657 women between 16 and 22 weeks of gestation were randomized to progesterone or placebo. All of them had a transvaginal ultrasound by a certified sonologist, 78 were found to have intra-amniotic debris, 112 women had cervical funnel on ultrasound.

A significant number of women with debris had a preterm labor (35% vs. 23%), as also women who cervical funnel (37% vs.21%).

After multivariate analysis, only amniotic fluid debris was found to be significantly associated with preterm birth prior to 34 or 32 weeks (aOR 1.85, 95% CI 1.00-3.44; aOR 2.78, 95% CI 1.42-5.45) respectively.

Earlier study have also shown that Amniotic fluid debris or ‘‘sludge’’ (AFS) is an independent risk factor for preterm delivery in women with CL< 25 mm. During Ultrasound it is recognized as a hyperechogenic matter in the amniotic fluid close to the uterine cervix and its prevalence is 22.3% in patients with preterm labor.

Abstract