Funding for this research was provided by:
Department of Medicine, University of California, San Francisco
NICHD/ORWH ([K12 HD052163])
Received: 8 May 2020
Accepted: 27 September 2020
First Online: 6 October 2020
Ethics approval and consent to participate
: Statistical Analysis Software version 9.4 (Cary, NC) was used to analyze data received by the California Preterm Birth Initiative at the University of California San Francisco as of March 1, 2020. Methods and protocols for the study were approved by the Committee for the Protection of Human Subjects (CPHS) which serves as the institutional review board (IRB) for the California Health and Human Services Agency (CHHSA). The role of the CPHS and other IRBs is to assure that research involving human subjects is conducted ethically and with minimum risk to participants.
: Not applicable.
: The authors declare that they have no competing interests. The authors have disclosed that that they have no significant relationships with, or financial interest in, any commercial companies pertaining to this article.