Basic Study
Copyright ©The Author(s) 2021. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Obstet Gynecol. Feb 10, 2021; 10(1): 1-15
Published online Feb 10, 2021. doi: 10.5317/wjog.v10.i1.1
Relationship between Mollicutes and spontaneous abortion: An epidemiological analysis
Maria Tânia Silva Oliveira, Caline Novais Teixeira Oliveira, Lucas Santana Coelho da Silva, Hellen Braga Martins Oliveira, Raquel Sousa Freire, Lucas Miranda Marques, Maria Luísa Cordeiro Santos, Fabrício Freire de Melo, Cláudio Lima Souza, Márcio Vasconcelos Oliveira
Maria Tânia Silva Oliveira, Caline Novais Teixeira Oliveira, Lucas Miranda Marques, Maria Luísa Cordeiro Santos, Fabrício Freire de Melo, Cláudio Lima Souza, Márcio Vasconcelos Oliveira, Instituto Multidisciplinar em Saúde, Universidade Federal da Bahia, Vitória da Conquista 45029094, Bahia, Brazil
Lucas Santana Coelho da Silva, Hellen Braga Martins Oliveira, Raquel Sousa Freire, Universidade Estadual Santa Cruz, Universidade Estadual Santa Cruz, Ilhéus 45662900, Bahia, Brazil
Author contributions: All authors contributed equally to this paper in terms of conception and design of the study, literature review and analysis, drafting and critical revision and editing, and final approval of the final version.
Institutional review board statement: This research was approved by the Health Foundation of Vitória da Conquista and approved by the Human Research Ethics Committee of the Universidade da Federal da Bahia, Instituto Multidisciplinar em Saúde, under the opinion 1.764 332.
Conflict-of-interest statement: There is no conflict of interest associated with the contributions by any of the senior authors or coauthors to this manuscript.
Data sharing statement: No additional data are available.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See:
Corresponding author: Fabrício Freire de Melo, MSc, PhD, Postdoc, Professor, Instituto Multidisciplinar em Saúde, Universidade Federal da Bahia, Rua Hormindo Barros, 58, Quadra 17, Lote 58, Vitória da Conquista 45029094, Bahia, Brazil.
Received: September 24, 2020
Peer-review started: September 24, 2020
First decision: December 21, 2020
Revised: December 21, 2020
Accepted: January 8, 2021
Article in press: January 8, 2021
Published online: February 10, 2021
Research background

Abortion is of great importance in public health, as it is among the main causes of maternal morbidity and mortality. In addition to sociodemographic- and lifestyle-related factors, studies have demonstrated that infections of the genital tract are associated with higher rates of abortion. The increased presence Mollicutes in the genitourinary tract may be related to higher rates of abortion. In addition, the diagnosis of this infection requires complex culture media, making the diagnosis more difficult, thus knowledge of the local epidemiological rates of these infections can guide clinical practice.

Research motivation

The importance of understanding the factors that may be related to spontaneous abortions is inadequate in clinical practice in order to avoid such outcomes and to ensure better public health principles.

Research objectives

To perform an epidemiological analysis of women with spontaneous abortion and placental colonization by Mollicutes in a maternity hospital.

Research methods

This is a cross-sectional study which involved the collection of data and biological material from women hospitalized due to spontaneous abortion or for term delivery. The sample analyzed consisted of 89 women who miscarried and 20 women who had full term pregnancy. Data collection took place in three stages: (1) Conducting research to identify information and clinical data in the medical records of patients hospitalized due to abortion; (2) Application of a semi-structured questionnaire to identify the patient's epidemiological profile; and (3) Collection of placental tissue. Placental samples were collected after the curettage procedure (abortion) and after placental expulsion (delivery), both performed by an obstetrician. Microbial identification of the fragments was performed by real-time polymerase chain reaction. In this study, the following explanatory variables were considered: (1) Sociodemographic variables; (2) Variables related to access to health services; (3) Variables related to lifestyle; and (4) Variables related to sexual and reproductive health, all of which were used to perform descriptive, univariate and multivariate analyses.

Research results

Colonization by Mollicutes was observed in 73.0% of the study participants. In the final model, placental colonization by Mollicutes was independently associated with the variables age [odds ratio (OR) = 7.55; CI: 2.37-24.03] and menarche (OR = 3.43; CI: 1.03-11.44). In this investigation, 73.0% of women who had a spontaneous abortion had colonization by Mollicutes. When comparing colonization between the two groups of participating women, there was an 8.12-fold risk of placental colonization by at least one Mollicutes species in those who had an abortion, compared to those who completed pregnancy. The final multivariate analysis model revealed a statistically significant association between placental microbial colonization by Mollicutes and abortion in relation to the variables: age, where women up to 29 years old had a 7.55-fold risk of spontaneous abortion, compared to those older than 29 years; menarche, where women who had menarche up to 13 years old had a 3.43-fold risk of miscarriage compared to those who had menarche over 13 years old; and change in eating habits, after the discovery of pregnancy, was a protective factor (OR = 0.16).

Research conclusions

Our study revealed a positive association between spontaneous abortion and placental colonization by Mollicutes. This signals the need for more investigations on this issue, in order to guide decision-making for the prevention of abortion.

Research perspectives

The information provided by this study is applicable for the development of guide-lines for the prevention of abortion.