# Pregnancy Due Date Calculator: EDD, Trimesters and Leave Estimate your due date from your last period, conception or IVF transfer, with trimesters and Singapore maternity, paternity and shared parental leave. Interactive tool: https://lookup.sg/tools/pregnancy-due-date-calculator ## How this works Pregnancy is counted as 40 weeks (280 days) from the first day of your last menstrual period, which is Naegele's rule. For cycles longer or shorter than 28 days, the due date moves by the difference: a 32-day cycle adds 4 days. From a known conception date the due date is 266 days later; from an IVF transfer it is 261 days after a day-5 embryo transfer or 263 days after a day-3 transfer. Trimesters run from week 1 to the end of week 13, week 14 to the end of week 27, and week 28 to birth. Term is 37 weeks (early term), 39 weeks (full term), 41 weeks (late term) and 42 weeks (post-term). For a Singapore citizen child, mothers get 16 weeks of Government-Paid Maternity Leave, starting up to 4 weeks before the birth, and fathers 4 weeks of Government-Paid Paternity Leave for babies born from 1 April 2025, taken within 16 weeks of the birth. Shared Parental Leave is 10 weeks for babies born from 1 April 2026 (6 weeks from 1 April 2025), split equally by default and used within 12 months. Leave dates here assume the baby arrives on the due date. ## FAQs ### How do I calculate my due date? Add 280 days (40 weeks) to the first day of your last period. If your last period started on 1 June 2026, your estimated due date is 8 March 2027, assuming a 28-day cycle. ### How is the due date worked out for IVF? Add 261 days to the transfer date for a day-5 (blastocyst) embryo, or 263 days for a day-3 embryo. A day-5 transfer on 15 June 2026 gives a due date of 3 March 2027. ### How long is maternity leave in Singapore in 2026? 16 weeks of Government-Paid Maternity Leave for a Singapore citizen child, if you have worked for your employer for at least 3 months before the birth. Otherwise, mothers covered by the Employment Act get 12 weeks. ### How much paternity and shared parental leave do fathers get? 4 weeks of Government-Paid Paternity Leave for Singapore citizen babies born from 1 April 2025, plus Shared Parental Leave of 10 weeks for babies born from 1 April 2026, split 5 weeks each by default. That is up to 30 weeks of paid leave between both parents. ### When does the second trimester start? At 14 weeks, counted from the first day of your last period. The third trimester starts at 28 weeks. For a due date of 8 March 2027, that is 7 September 2026 and 14 December 2026. ## Sources - [ACOG Committee Opinion 700: Methods for estimating the due date](https://www.acog.org/clinical/clinical-guidance/committee-opinion/articles/2017/05/methods-for-estimating-the-due-date) - [ACOG Committee Opinion 579: Definition of term pregnancy](https://www.acog.org/clinical/clinical-guidance/committee-opinion/articles/2013/11/definition-of-term-pregnancy) - [MOM: Maternity leave eligibility and entitlement](https://www.mom.gov.sg/employment-practices/leave/maternity-leave/eligibility-and-entitlement) - [MOM: Planning your maternity leave](https://www.mom.gov.sg/employment-practices/leave/maternity-leave/planning-your-leave) - [MOM: Paternity leave](https://www.mom.gov.sg/employment-practices/leave/paternity-leave) - [MSF: 10 weeks of Shared Parental Leave from 1 April 2026](https://www.msf.gov.sg/media-room/article/10-weeks-of-shared-parental-leave-from-1-april-2026) --- Source: Lookup (https://lookup.sg) · Data as of October 2026 · Listings compiled from Singapore government open data (data.gov.sg), OneMap and Overture Maps places. Free listings never show contact details; contact details appear only on Lookup Verified listings.