During normal pregnancy, maternal hormones and locally acting cytokines play a key role in regulating the onset of labor, cervical ripening, uterine contraction, and delivery. Maternal infections during pregnancy have been demonstrated to perturb this normal cytokine and hormone-regulated gestation, sometimes resulting in preterm labor, preterm premature rupture of membranes, and preterm low birth weight (PLBW), i.e., < 2,500 g and < 37 weeks of gestation. Our research focus has been to determine whether periodontal infections can provide sufficient challenge to the mother to trigger PLBW. New experiments from 48 case-control subjects have measured gingival crevicular fluid (GCF) levels of PGE(2) and IL-1-beta to determine whether mediator levels were related to current pregnancy outcome. In addition, the levels of 4 periodontal pathogens were measured by using microbe-specific DNA probes. Results indicate that GCF-PGE(2) levels are significantly higher in PLBW mothers, as compared with normal birth weight (NBW) controls (131.4 +/- 21.8 vs. 62.6 +/- 10.3 [mean +/- SE ng/mL], respectively, at P = 0.02). Furthermore, within primiparous PLBW mothers, there was a significant inverse association between birth weight (as well as gestational age) and GCF-PGE(2) levels at P = 0.023. These data suggest a dose-response relationship for increasing GCF-PGE(2) as a marker of current periodontal disease activity and decreasing birth weight. Microbial data indicate that 4 organisms associated with mature plaque and progressing periodontitis--bacteroides forsythus, Porphyromonas gingivalis, Actinobacillus actinomycetemcomitans, and Treponema denticola--were detected at higher levels in PLBW mothers, as compared to NBW controls. These data suggest that biochemical measures of maternal periodontal status and oral microbial burden are associated with current PLBW.

Introduction: Preterm birth is the leading cause of neonatal morbidity and mortality. Spontaneous Preterm Birth (sPTB) has many and varied causes but is known to be strongly associated with a short or shortening cervix in the midtrimester of pregnancy. The strongest risk factor for sPTB is a previous sPTB.In women with a history of sPTB, we can offer surveillance and treatments which have been proven to reduce the risk of sPTB, such as cervical cerclage and vaginal progesterone supplementation. Alongside other indications, we currently use 25 mm or shorter as a ''trigger threshold" for offering cervical cerclage treatment in the Preterm Birth Prevention Clinic at The National Maternity Hospital. Aim: To determine if using gestation-specific centiles instead of a 25 mm cut-off for cervical length changes the antenatal management of women at high risk of sPTB. Method: This was a retrospective chart review of all women attending the preterm birth clinic over the 2year period 2018-2020 in a large tertiary referral unit in Dublin, Ireland. Demographic details, obstetric history, preterm birth risk factors and preventative treatments offered were collected and analysed. Cervical lengths were measured with ultrasound using a standardised protocol and all performed or supervised by 2 experienced sonographers. Results: A total of 200 patients with known risk factors for sPTB attended the Preterm Birth Surveillance Clinic at the National Maternity Hospital during the study period. Of these, 36/200 (18%) went on to deliver again prior to 37 weeks despite attending the clinic +/-receiving interventions & this group are the focus of this paper. The indications for surveillance in this group that had a recurrent sPTB included recurrent second-trimester pregnancy losses/preterm delivery < 34 weeks (26/36 (72%)), cervical trauma (including treatment of CIN) (12/36 (33%)), congenital abnormalities (1/36 (2.8%)), uterine anomaly (1/36 (2.8%)) and placental bleeding (1/36 (2.8%)). There was one smoker in this series. Funnelling was observed in 3/36 cases (8.3%). Of the 36 patients, an additional 15 would have received a cerclage had gestation-specific centiles, i.e., <5th centile, been used and an additional 10/36 (28%) would have been offered progesterone therapy. Conclusion:In those at high risk of preterm birth, the use of gestation-specific centiles for cervical length increases the proportion of patients that would be eligible for cervical cerclage. It is unclear whether this would change clinical outcome.

Objectives: To determine the use of transvaginal ultrasound cervical length in fetal second trimester scanning for preventing spontaneous preterm delivery, the management and treatments for pregnancy prolongation for an improved neonatal outcome. Methods: We performed a retrospective study of 2,018 asymptomatic women attending the routine second trimester ultrasound scanning, examined by transvaginal sonography during one year. We diagnosed patients with low cervical length, defined as ≤25mm. Results: 20 of the 2,018 women (0.99 %) showed a low cervical length. Mean age was 32.9 years. 12 patients were primigravidas and 8 were multigravida (only 1 with history of preterm labour). Most of them were singleton pregnancies (N = 18). A history of cervical conisation was reported in 7 women. The patients with cervical length between 15-25mm were treated with vaginal progesterone (N = 13), while the patients with cervical length <15mm and twin pregnancies were treated with cervical pessary and vaginal progesterone (N = 7). 6 patients in the first group required a cervical pessary because of cervical shortening and 1 women in the second group required a rescue cerclage because of membranes prolapse. The mean cervical shortening in the first group was 7.35mm and in the second group was 7.7mm. There were 6 patients with episodes of threatened premature labour (but only 3 were finally preterm labour) and 2 patients with preterm premature rupture of membranes. The remaining patients (N = 15) had a spontaneous delivery at term (> 37 weeks). All of them were vaginal deliveries except two Caesarean section. Conclusions: The use of cervical length assessment in fetal second trimester ultrasound, previously of possible threatened premature labour, could be useful to select low cervical length as risk factor in asymptomatic pregnant women. The combination of vaginal progesterone and cervical pessary could be included as appropriate preterm birth prevention strategies, but further studies would be necessary to reassure it.