The effects of vaginal flora changes on perinatal outcomes in single pregnancies which are monitored and treated due to the risk of preterm labor

Objective: Preterm labor is defined as the labor occurring before 37th week of gestation. If this condition is not treated or suppressed before 37th gestational week, preterm delivery happens. Preterm delivery is the premature delivery of the neonate which is the predominant cause of morbidity and mortality during childhood. To prevent preterm labor and delivery, vaginal progesterone, cervical pessary or cerclage treatment can be performed. This thesis study aims to investigate how the alterations in vaginal microbiota affect perinatal outcomes in women with singleton pregnancy after undergoing progesterone, pessary and cerclage treatment. Methods: This study was undertaken at Afyonkarahisar Health Sciences University between 25.07.2022 and 01.08.2024. This is a review of 60 women with first trimester singleton pregnancy who underwent vaginal progesterone (200 mg/day), elective cervical pessary and cerclage treatment for preventing preterm birth. The inclusion criteria were being aged between 20 and 40 years, having a history of preterm delivery and cervical length <25 mm, having a history of cervical insufficiency, and being devoid of congenital uterine anomalies. The participants had pelvic examination in 4th week and 4th month (16th week) following vaginal progesteron, pessary or cerclage treatment. Wet smears, vagina and urine cultures were obtained during pelvic examinations. Besides Nugent scores, the outcomes of vagina and urine cultures were noted. The pregnant women to whom vaginal progesterone, pessary and cerclage were administered were compared with respect to microbiological and perinatal outcomes. Results: Vaginal progesterone tretament was administered to 22 out of 60 pregnant women (36,7%) while cervical pessary was placed in 17 patients (28,3%) and cerclage was performed in 21 patients (35,0%). The frequency of assisted pregnancy was significantly lower among the women receiving progesterone treatment (p=0,013). Nugent scores, vaginal and urine cultures obtained at the first and second pelvic examinations were statistically similar for the women to whom vaginal progesterone, cervical pessary and cerclage were administered (p>0,05 for all). Moreover, the progesterone, pessary and cerclage groups were statistically similar with respect to miscarriage, delivery route, neonatal sex, need for neonatal intensive care, gestational age at birth, first and fifth minute Apgar scores (p>0,05 for all). Birth weight was statistically lower for neonates born to women who had pessary than the women who had progesterone and cerclage treatment (p=0,025). The outcome was positive in 47 out of 60 vaginal cultures (78,3%) that were obtained at the first pelvic examination. First minute Apgar score was significantly lower in the neonates born to women who had positive vaginal culture than those born to women who had negative vaginal culture at the first pelvic examination (p=0,016). The outcome was positive in 30 out of 56 vaginal cultures (53,6%) that were collected at the second pelvic examination. The frequency of preterm birth was significantly lower among the women who had positive vaginal culture than the women who had negative vaginal culture at the second pelvic examination (p=0,029). The outcome was positive in 4 out of 60 urine cultures (6,7%) that were obtained at the first pelvic examinationa and the outcome was positive in 8 out of 56 urine cultures (14,3%) that were collected at the second pelvic examination. The women who had positive and negative urine cultures at the first and second pelvic examinations were statistically similar in aspect of preterm birth, need for neonatal intensive care, gestational age at birth, birth weight, first and fifth Apgar scores (p>0,05 for all). Conclusion: There should be a period of observation for the pregnant women to whom vaginal progesterone, cervical pessary and cerclage would be administered. Moreover urogenital cultures should be obtained and antibiotics should be begun in case of positive results. The patients should be counseled that preterm birth risk would not be increased and perinatal outcomes would not be impaired if urogenital cultures yielded positive results. It should be also emphasized that the benefits provided by vaginal progesterone, cervical pessary and cerclage would overcome the hazards related with their effects on vaginal flora and succeeding urogenital infections. Keywords: Infection, Pesser, Preterm Delivery, Progesterone, Cerclage