EVALUATION OF GENITOURINARY INFECTION IN PRETERM LABOUR: A DESCRIPTIVE CROSS-SECTIONAL STUDY

Introduction: Preterm labour is defined as the occurrence of regular uterine contractions (≥ 4 in 20 minutes or ≥ 8 in 1 hour) and cervical changes (effacement ≥ 80% and dilatation ≥ 1cm) in women with intact fetal membrane and gestational age less than 37 weeks. Genitourinary infection is the most important cause of preterm labour. The aim of this study was to determine the role of Genitourinary infection in causation of preterm labour. Methods: This is a descriptive cross sectional study done at National Medical College Teaching Hospital from 10 November 2021 to 9 November 2022 after obtaining IRC (F-NMC/549/078-79). Total of 90 patients in preterm labour fulfilling the inclusion criteria were enrolled in this study after taking informed consent. Clinical examination was done, vaginal swab, endocervical swab and urine samples were sent to microbiological department for examination. Preformed proforma were used to record the demographic, clinical finding and result of investigation. The data was analyzed statistically using SPSS 22 and mean age, frequency and prevalence of genitourinary infection were calculated. Results: In this study, 90 patients of preterm labour were enrolled. The mean age group of patients was 23.61 ± 4.25 years. Genital infection compromised of 41%, high vaginal swab showed 30% prevalence and endocervical swab showed 20% prevalence. The most common organism identified in genital infection was Gardenella vaginalis 55.55%. The prevalence of Urinary tract infection was 40% where E.coli was the most common organism 66.66%. Conclusions: Genitourinary tract infection plays an important role in causation of preterm labour and can easily be diagnosed with routine urine examination, urine culture and vagino - cervical swab. The prevalence of genital infections and urinary tract infection was 41% and 40% respectively. Gardnerella vaginalis was the most common pathogen identified in genital tract whereas E.coli was leading cause of UTI in Preterm labour patients.


INTRODUCTION
Preterm labour (PTL) leading to preterm birth is worldwide the most challenging problem in obstetrics. 1 It is one of the leading cause of perinatal morbidity and mortality and is one of the major public health problems, especially with reference to mortality, disability and health care expenses. 2 It is onset of labour after the period of viability and before completion of 37 weeks. 3 About 15 million babies are preterm each year (5% to 18% of all deliveries). 4 Prematurity is the leading cause of neonatal deaths and now the second leading cause of death. 4 Genitourinary infections (GUI's) are prevalent during pregnancy and are recognized as an important cause of premature labour. A imbalance in the vaginal flora favors the colonization of the urogenital system by microorganisms, which can complicate a pregnancy. 5 It is mostly widespread during unhygienic conditions and during pregnancy and considered as an important cause. 6 Bacterial vaginosis, vulvovaginal candidiasis and trichomoniasis are responsible for 90% of cases of infectious vulvovaginitis, which lead to complications such as pelvic inflammatory disease, postabortion endometritis, chorioamnionitis, and premature labour. 5 Majority of these cases of idiopathic prematurity are thought to be due to subclinically ascending urogenital infection. 7 There is compelling evidence of a causal association between intrauterine infection and spontaneous preterm and delivery. 8 This study aimed to determine the role of genitourinary infection in causation of preterm labour. Therefore, there is a need to assess preterm birth risk factors to predict preterm birth and prevent timely intervention to reduce the severity of complications.

Date of Submission
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MATERIALS AND METHODS
This descriptive cross-sectional study was conducted in the Department of Obstetrics and Gynaecology of National Medical College and Teaching Hospital for a duration of one year from 10 th November 2021 to 9 th November 2022. The ethical approval was obtained from the Institutional Review Committee of the National Medical College and Teaching Hospital (Ref. F-NMC/549/078-79). Pregnant women with gestation age between 28 to 37 weeks in labour presenting in hospital were admitted. The patients fulfilling the inclusion criteria were included in this study. Genital swabs and urine samples were sent to Microbiology Department for analysis after clinical examination. The investigation was followed up and evaluated for this study.
History regarding antenatal care, number of visits in ANC clinic, place of visit and any antenatal investigations done were recorded. Detailed obstetric history including LMP, EDD and period of gestation of present pregnancy, past obstetric history and outcomes including history of abortions, preterm birth and IUFD were noted. Personal history like smoking, alcohol intake or any substance abuse were taken. Medical disorders, drug intake and any complication encountered during the index pregnancy were also noted. EDD was confirmed by date of last menstruation and/or ultrasound in first trimester.
Careful clinical examination including general examination and systemic examination was done. Blood pressure and pulse were recorded. On per abdominal examination, height of fundus, lie, presentation, characteristics of uterine contraction was noted and fetal heart sound was auscultated. Per speculum examination was done in all patients and evaluated for any abnormal vaginal discharge. The characteristic of the discharge like consistency, color and odor was noted. One endocervical swab and one high vaginal swab was collected. Per vaginum examination was done to see cervical changes like dilatation, effacement and status of the membrane. Routine blood investigations were sent like haemoglobin, blood grouping, random blood sugar, platelet, total leucocyte count, differential leucocyte count, prothrombin time, serology for HIV and HBsAg. A clean catch mid-stream urine was sent for routine microscopic examination, culture and sensitivity to antibiotics. Vaginal swab was used for the identification of organisms examined microscopically. Swab was used to test with 10% potassium hydroxide, to check for the release of amine odor and to see yeast like forms, budding or branching hyphae. It was also used for gram staining, culture and sensitivity to antibiotics. Endocervical swab was used for gram staining and for culture and sensitivity.

Selection Criteria
All participants who meet inclusion criteria in study period were enrolled in the study.
Inclusion criteria -Gestational age between 28 to 37 weeks, singleton, live pregnancy, uterine contractions occurring at a frequency of four in 20 minutes or eight in 60 minutes plus progressive change in the cervix, cervical dilatation greater than 1 cm, cervical effacement of 80% or greater, in addition to painful or painless uterine contraction, symptoms such as pelvic pressure, menstrual like clamps, watery or bloody vaginal discharge and pain in the low back have been empirically associated with impending preterm birth.
Exclusion criteria -Uterine anomaly, multiple pregnancy, clinical chorioamnionitis, antepartum hemorrhage, pregnancy induced hypertension, maternal diabetes mellitus, use of antibiotics in preceding two weeks.
The data collected were entered daily. Analysis of the data was done by using SPSS version 22 software. These findings were then presented in the form of tables, graphs and diagrams using Microsoft Excel 2021. SPSS version 22 was the software used for calculation and tabulation of data. The final results were discussed and the conclusion was derived.

RESULTS
A total number of 90 patients of Preterm labour attending in the department of Obstetric and Gynaecology of National Medical College Teaching Hospital, Birgunj who gave consent were included in this study. All the patients meeting the inclusion criteria were evaluated for genitourinary infection. Urine sample, one high vaginal swab and one endocervical swab were taken and sent for microbiological evaluation. Endocervical Swab among 90 preterm patients 20% of women were positive for organism. E.coli was the commonest pathogen accounting 9 (50%), followed by Staphylococcus 7 (38.8%) and pseudomonas 2 (11.11%).

DISCUSSION
GUI's during pregnancy are an important cause of Preterm labour. GUI's generally present with multifactorial or unknown etiology. Several studies have addressed the association of GUIs with pregnancy. 5,9 Majority of women belonged to the age group 21-25 years with mean age group 23 ± 4.25 years which is comparable study of Safari et al. 10 published in 2017 which showed highest incidence of PTL observed in women of age group 23 ± 6.34 years.
Edwards RK et al. 11 and Giraldo P C et al. 5 reported mean age of 25 ± 5.7 years and 25 ± 3.2 years respectively.
In our study, we found the mother who had poor ANC (unbooked) 63.3% were more prone to genitourinary infection. The finding is comparable with the study conducted by Safari et al. 10  Present study shows that the overall prevalence of UTI in PTL was 40% which was detected by presence of organism in urine culture which was similar to the other report of Giraldo P C et al., 5 Akobi OA et al. 18 The prevalence was similar to one study done in rural hospital of Nepal (51.8%) Yadav LK et al. 19 which showed the prevalence of UTI in pregnancy.
This study reflect E.coli was most common isolated organism 66.66% of bacteriuric women. This was similar to study conducted by Acosta-Terriquez JE et al. 20 which was 74.4%. Similarly Kamal HA et al. 21 Verma I et al. 22 Tedesco RP et al. 23 study showed E.coli as the most common organism isolated from urine culture.
In this study, genital tract infection were evaluated by High vaginal swab and endocervical swab. The prevalence of High vaginal swab were 30% and endocervical swab were 20%. Genital tract infection prevalence was 41.11%. Similar prevalence were observed in a study of Lamichhane P et al. 24 Edwards et al. 11 Verma I et al. 22 with prevalence of 40%, 33.6%, 21.15% respectively. Spontaneous preterm deliveries that occur before 34 weeks of gestation, have been strongly associated with intrauterine infection. 25 Bacterial vaginosis (40.74%) was the most common organism isolated from the high vaginal swab in our study. Data presented in various work have demonstrated strong associations between prevalent infection of BV and preterm birth. 8,11,[26][27][28] This study showed isolation of other organism too. Second most common organism was found to be Candida albicans 22.22% which showed similarity with the study of Lamichhane et al. 24

LIMITATIONS
The study was hospital based and findings might not be not representative of the general population. Due to the limited duration and number of samples, the projected result cannot be conclusively applied to large populations, so study of a larger multicentric trial is recommended.

CONCLUSION
This study showed Genitourinary infection plays an important role in causation of preterm labour and is a leading cause of Preterm birth. Genitourinary tract infection can easily be diagnosed with routine urine examination, urine culture and vagino-cervical swab. The prevalence of genital tract infection in preterm labour was 41% in this study. The prevalence of urinary tract infection in preterm labour was 40% in this study. Gardnerella vaginalis was the most common pathogen identified in genital tract infection in preterm labour patients accounting 15 (55.55%). Escherichia coli was the most common organism isolated in urinary tract infection in preterm labour patients accounting 24 (66.66%).