Preterm Labor Prevention Using Vaginal Antiseptics Prior to 16 Weeks of Gestation

Clinical implications of the study:

The clinical implications of our project would be to counteract the effect of pathogenic bacteria from the beginning of pregnancy (outside the teratogenic period) with the administration of the CLX ovules and thus enhance the action of the normal vaginal microbiota in the pregnant patient, since the glycogen available due to hormonal action favours the growth and development of lactobacillus, responsible for its protective activity against pathogens during pregnancy.

Sample size:

The approximate number of births per year in Spain is 370,000. The minimum number of patients to be recruited would be 400 with a 95% confidence interval.

Patients were recruited as they attended the consultation where the PI and/or collaborators were present.

Variables:

• maternal age,
• parity,
• Gestational age (GA) at examination in weeks,
• GA at delivery in weeks,
• Interval between ultrasound and delivery,
• Birth weight (BW), BW centile,
• fetal gender,
• onset of labor (elective cesarean section, induction of labor and spontaneous onset of labor),
• mode of delivery (cesarean section for abnormal cardiotocography, failure to progress or elective, assisted delivery and spontaneous delivery),
• Apgar scores at 5 minutes,
• neonatal cord arterial hydrogen potential( pH)
• Newborn destination: ward, neonatal, neonatal intensive care unit
• Type of event triggering preterm birth:Premature rupture of membranes /Uterine dynamics + cervical modifications

Statistical analysis Continuous variables were presented as mean and standard deviations (SD), median and interquartile range (IQR), while categorical variables were presented as absolute numbers and relative frequencies. Characteristics between both cohorts were compared by mean of Mann- Whitney and Fisher tests. Finally, to assess the validity of results and ensure consistency an additional multivariable analysis was performed adjusting for clinical parameters, to evaluate the odds ratio (OR) of the different determinants in the prediction of preterm birth. Finally, preterm birth incidence was calculated for specific groups selected according to the multivariable analysis result. Statistical analysis and graphs were done using Graph Pad Prism®, Mac version 9.0.1, and Stat Plus® Mac Pro version 8.0.1.s. Permissions were obtained from La Fe hospital review board and from the Valencian Autonomic Government health authorities (reference: PLUVA, date 4-2-2021). Written informed consent was retrieved to participate in the study. The authors report no conflicts of interest.

Quality control:

All analyses were performed on a single sample of patients who met the selection criteria and who had all the information required for the variables to be analysed.

In cases where it was not possible to obtain this information, the following were excluded from the study

Inclusion criteria

- Healthy pregnant patients from the 9 weeks until 15weeks 6 days who attend the first trimester check-up

Exclusion criteria

Patients with a history of previous preterm birth.

• Patients with vaginal bleeding during the first trimester.
• Patients with abnormalities detected in the first trimester ultrasound scan.
• Twin pregnancies
• Patients with a known allergy to the topical use of Chlorhexidine in any of its forms of presentation.