Additional Proxy Soliciting Materials (Form DEFA14A)

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

SCHEDULE 14A

Proxy Statement Pursuant to Section 14(a) of

the Securities Exchange Act of 1934

(Amendment No. )

Filed by the Registrant ☒

Filed by a Party other than the Registrant ☐

Check the appropriate box:

SERA PROGNOSTICS, INC.

(Name of Registrant as Specified In Its Charter)

(Name of Person(s) Filing Proxy Statement, if other than the Registrant)

Payment of Filing Fee (Check the appropriate box):

Your Vote Counts! SERA PROGNOSTICS, INC. 2026 Annual Meeting Vote by June 3, 2026 11:59 PM ET SERA PROGNOSTICS The Pregnancy Company® SERA PROGNOSTICS, INC. 2749 EAST PARLEYS WAY, SUITE 200 SALT LAKE CITY, UT 84109 You invested in SERA PROGNOSTICS, INC. and it's time to vote! You have the right to vote on proposals being presented at the Annual Meeting. This is an important notice regarding the availability of proxy materials for the stockholder meeting to be held on June 4, 2026. Get informed before you vote View the Notice and Proxy Statement, Annual Report and Form 10-K online OR you can receive a free paper or email copy of the material(s) by requesting prior to May 21, 2026. If you would like to request a copy of the material(s) for this and/or future stockholder meetings, you may (1) visit www.ProxyVote.com, (2) call 1-800-579-1639 or (3) send an email to [email protected]. If sending an email, please include your control number (indicated below) in the subject line. Unless requested, you will not otherwise receive a paper or email copy For complete information and to vote, visit www.ProxyVote.com Control # Smartphone users Point your camera here and vote without entering a control number Vote Virtually at the Meeting* June 4, 2026 9:00 a.m. Mountain Time Virtually at: www.virtualshareholdermeeting.com/SERA2026 *Please check the meeting materials for any special requirements for meeting attendance.

Vote at www.ProxyVote.comTHIS IS NOT A VOTABLE BALLOT This is an overview of the proposals being presented at the upcoming stockholder meeting. Please follow the instructions on the reverse side to vote these important matters. Voting Items 1. Election of Directors Nominees: 01) Jeffrey T. Elliott 02) Kim Kamdar, Ph.D. 03) Sandra A.J. Lawrence 2. Ratification of the appointment of Ernst & Young LLP as our independent registered public accounting firm for our fiscal year ending December 31, 2026. NOTE: The proxy holders will vote in their discretion on any other business as may properly come before the Annual Meeting or any adjournment or postponement thereof. Board Recommends For For Prefer to receive an email instead? While voting on www.ProxyVote.com, be sure to click "Delivery Settings".