ABSTRACT
Background Evidence for the impact of COVID-19 during the second and the third trimester of pregnancy is limited to a relatively small series, while data on the first trimester are scant. With this study we evaluated COVID-19 infection as a risk factor for spontaneous abortion in first trimester of pregnancy.
Methods Between February 22 and May 21, 2020, we conducted a case-control study at S. Anna Hospital, Turin, among first trimester pregnant women, paired for last menstruation. The cumulative incidence of COVID-19 was compared between women with spontaneous abortion (case group, n=100) and those with ongoing pregnancy (control group, n=125). Current or past infection was determined by detection of SARS-CoV-2 from nasopharingeal swab and SARS- CoV-2 IgG/IgM antibodies in blood sample. Patient demographics, COVID-19-related symptoms, and the main risk factors for abortion were collected.
Findings Twenty-three (10.2%) of the 225 women tested positive for COVID-19 infection. There was no difference in the cumulative incidence of COVID-19 between the cases (11/100, 11%) and the controls (12/125, 9.6%) (p=0.73). Logistic regression analysis confirmed that COVID-19 was not an independent predictor of abortion (1.28 confidence interval 0.53-3.08).
Interpretation COVID-19 infection during the first trimester of pregnancy does not appear to predispose to abortion; its cumulative incidence did not differ from that of women with ongoing pregnancy.
Competing Interest Statement
The authors have declared no competing interest.
Funding Statement
Research university funds
Author Declarations
I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained.
Yes
The details of the IRB/oversight body that provided approval or exemption for the research described are given below:
The study was approved by the Institutional Review Board of the City of Health and Science of Torino (Reference number: 00171/2020)
All necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived.
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Footnotes
↵* Joint first authors.
Disclosure: The authors report no conflict of interest
Financial Support: research university funds
Data Availability
The dataset generated during during the current study is available from the corresponding author on reasonable request.