Factors associated with having COVID-19 among unvaccinated pregnant and non-pregnant women in Metro Manila, Philippines: a multicentre longitudinal cohort study

Erlidia F Llamas-Clark; Francisco M Heralde; Mayan U Lumandas; Maria Stephanie Fay S Cagayan; Maria Esterlita T Villanueva-Uy; Leilani C Chavez-Coloma; Eleyneth I Valencia; Charizze Anne S Cabana; Lea Bernadette H Espinosa; Cynthia U Anzures; Maria Lu D Andal; Carolina Paula C Martin; Patricia Nevira V Suarez; Celine D Quanico; Julia B Beltran; Vanessa D de Guzman; Ryan B Capitulo; Arlene R Dominguez; Abygail L Recio; Jeremiah F Feliciano; Emmanuel S Baja; Paulyn Jean B Rosell-Ubial

doi:10.1136/bmjopen-2022-070688

Factors associated with having COVID-19 among unvaccinated pregnant and non-pregnant women in Metro Manila, Philippines: a multicentre longitudinal cohort study

BMJ Open. 2023 Apr 17;13(4):e070688. doi: 10.1136/bmjopen-2022-070688.

Authors

Erlidia F Llamas-Clark^{1

2}, Francisco M Heralde³, Mayan U Lumandas⁴, Maria Stephanie Fay S Cagayan⁵, Maria Esterlita T Villanueva-Uy², Leilani C Chavez-Coloma⁶, Eleyneth I Valencia⁶, Charizze Anne S Cabana⁶, Lea Bernadette H Espinosa⁶, Cynthia U Anzures⁷, Maria Lu D Andal⁷, Carolina Paula C Martin⁸, Patricia Nevira V Suarez⁹, Celine D Quanico⁹, Julia B Beltran⁹, Vanessa D de Guzman¹⁰, Ryan B Capitulo¹⁰, Arlene R Dominguez¹¹, Abygail L Recio¹¹, Jeremiah F Feliciano¹², Emmanuel S Baja^{13

14}, Paulyn Jean B Rosell-Ubial¹⁵

Affiliations

¹ Department of Obstetrics and Gynecology, University of the Philippines Manila College of Medicine, Manila, Philippines efllamasclark@up.edu.ph.
² Institute of Child Health and Human Development, National Institutes of Health, University of the Philippines Manila, Manila, Philippines.
³ Department of Molecular Biology and Biochemistry, University of the Philippines Manila College of Medicine, Manila, Philippines.
⁴ Department of Virology, Research Institute for Tropical Medicine, Muntinlupa, Philippines.
⁵ Department of Pharmacology and Toxicology, University of the Philippines Manila College of Medicine, Manila, Philippines.
⁶ Department of Obstetrics and Gynecology, Jose R Reyes Memorial Medical Center, Manila, Philippines.
⁷ Department of Obstetrics and Gynecology, Dr Jose Fabella Memorial Hospital, Manila, Philippines.
⁸ Department of Internal Medicine, Ospital ng Maynila Medical Center, Manila, Philippines.
⁹ Department of Obstetrics and Gynecology, Ospital ng Maynila Medical Center, Manila, Philippines.
¹⁰ Department of Obstetrics and Gynecology, Justice Jose Abad Santos General Hospital, Manila, Philippines.
¹¹ Department of Obstetrics and Gynecology, Sta Ana Hospital, Manila, Philippines.
¹² University of the Philippines Manila College of Medicine, Manila, Philippines.
¹³ Institute of Clinical Epidemiology, National Institutes of Health, University of the Philippines Manila, Manila, Philippines.
¹⁴ Department of Clinical Epidemiology, University of the Philippines Manila College of Medicine, Manila, Philippines.
¹⁵ Department of Health Policy and Administration, University of the Philippines Manila College of Public Health, Manila, Philippines.

Abstract

Objective: To determine the potential risk factors associated with having COVID-19 among unvaccinated pregnant and non-pregnant women.

Design: A multicentre prospective cohort study among eligible women in Metro Manila, Philippines, from 2020 to 2022.

Setting: Five national and local hospital research sites altogether recruited and screened 500 consenting eligible individuals.

Participants: Pregnant and non-pregnant participants meeting the eligibility criteria were admitted for a reverse-transcription PCR determination of SARS-CoV-2, pregnancy testing and ultrasound, and an interview with an administered questionnaire.

Exposures: Primary exposure was pregnancy; secondary exposures involve sociodemographic, lifestyle and obstetric-gynaecologic factors.

Outcome measure: Outcome being measured was COVID-19 status.

Results: The significant COVID-19 risk factors were: pregnancy (PR=1.184, 95% CI 1.096, 1.279), having a white-collar job (PR=1.123, 95% CI 1.02, 1.235), travelling abroad (PR=1.369, 95% CI 1.083, 1.173) and being infected by at least one vaccine-preventable disease (VPD) (PR=1.208, 95% CI 1.113, 1.310). Protective factors included having graduate-level education (PR=0.787, 95% CI 0.649, 0.954), immunisation against a VPD (PR=0.795, 95% CI 0.733, 0.862) and practising contraception (PR=0.889, 95% CI 0.824, 0.960).

Conclusion: This study is the first in the country to determine the risks influencing COVID-19 infection among unvaccinated pregnant and non-pregnant women. Pregnancy is a significant risk for COVID-19 among women in Metro Manila. Educational attainment and positive health behaviours seem to confer protection. Occupations and activities that increase the frequency of interactions, as well as history of communicable diseases may predispose women to COVID-19. Further studies are needed to elucidate the development of the disease in pregnant women, including the maternal and neonatal effects of COVID-19 via potential vertical mechanisms of transmission.

Keywords: COVID-19; EPIDEMIOLOGIC STUDIES; OBSTETRICS; Public health.

Publication types

Multicenter Study
Research Support, Non-U.S. Gov't

MeSH terms

COVID-19* / epidemiology
Female
Humans
Infant, Newborn
Longitudinal Studies
Philippines / epidemiology
Pregnancy
Pregnancy Complications, Infectious* / epidemiology
Prospective Studies
SARS-CoV-2