C-Section Date Calculator (Scheduled Cesarean at 39 Weeks)
Find the date you reach 39 weeks (or 37, 38 or 40 weeks) for a scheduled cesarean birth from your due date, with the weekday, the nearest weekday and the term category.
How it works
C-section date = due date − (280 − (weeks × 7 + days)) days · 39 weeks 0 days = due date − 7 days · early term 37+0 to 38+6, full term 39+0 to 40+6, late term 41+0 to 41+6, post-term 42+0 or more
When a cesarean is planned without a medical reason to deliver earlier — for example a repeat cesarean or a breech baby — ACOG recommends scheduling it at or after 39 weeks 0 days, because babies born at 37–38 weeks (early term) have more breathing and feeding problems and NICU admissions. 39 weeks 0 days is exactly 7 days before the due date. Earlier dates (37–38 weeks) are reserved for medical indications such as placenta previa, some twin pregnancies or maternal illness. Hospitals rarely schedule elective surgery at weekends, so the calculator also shows the next weekday.
Worked example
With a due date of March 20, 2027, 39 weeks 0 days is 280 − 273 = 7 days earlier: Saturday, March 13, 2027 (full term). Because that is a weekend, the nearest weekday on or after it is Monday, March 15, 2027 (39 weeks 2 days).
Sources: ACOG Committee Opinion No. 765: Avoidance of nonmedically indicated early-term deliveries (2019) · ACOG Committee Opinion No. 579: Definition of term pregnancy
Frequently asked questions
At how many weeks is a planned C-section done?
Without a medical reason to deliver earlier, ACOG and most guidelines recommend a planned cesarean at 39 weeks 0 days or later, which is 7 days before your due date or later.
Why not schedule a C-section at 37 or 38 weeks?
Babies born at 37–38 weeks (early term) have higher rates of breathing problems, low blood sugar, jaundice and admission to neonatal care than babies born at 39 weeks or later. Earlier delivery is only advised for specific medical reasons.
What if labor starts before my C-section date?
Go to the hospital as instructed. If labor starts before the planned date, the cesarean is usually done then, and your team will check your baby’s position and wellbeing.
Is my C-section date the same as my due date?
No. Your due date marks 40 weeks 0 days. A cesarean scheduled at 39 weeks falls one week before, and the date your hospital gives may vary by a few days depending on operating room availability.
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This calculator is for education only and does not replace your midwife, obstetrician or doctor. Contact your care team straight away about bleeding, fluid leaking, reduced baby movements, severe pain, fever or anything that worries you.