Pregnancy Due Date

Introduction to the Pregnancy Due Date Calculator

The Pregnancy Due Date Calculator estimates your Estimated Date of Delivery (EDD) using Naegele's Rule: EDD = LMP + 280 days, or LMP + 9 months + 7 days. It also works in reverse from a known conception date (EDD = conception + 266 days) or from an early ultrasound CRL (crown-rump length) measurement.

Indian expectant mothers use this tool to plan antenatal visits at government PHCs or private hospitals like Apollo, Fortis and Cloudnine, schedule Tdap and influenza vaccinations, and apply for maternity leave under the Maternity Benefit Act (26 weeks paid). It is also useful for Garbhavastha rituals like Godh Bharai (baby shower) timing in the 7th month.

You enter the first day of your Last Menstrual Period (LMP) and average cycle length (default 28 days). The calculator returns EDD, current pregnancy week and day, trimester, weeks remaining, and recommended antenatal milestones like NT scan (11-13 weeks), anomaly scan (18-22 weeks), and GTT (24-28 weeks).

Who Should Use This Pregnancy Due Date Calculator

First-time mothers in Mumbai newly confirmed pregnant via beta hCG blood test or home kit use it to set initial expectations and book their first OB-GYN visit between 8-10 weeks.

Working professionals in Bengaluru planning maternity leave at 8 IT companies need accurate EDD to file HR forms 60 days in advance under the 26-week paid leave policy.

Couples in Delhi tracking IVF cycles use the conception-date input since their fertilisation date is known precisely from embryo transfer day at clinics like Indira IVF or Nova.

Mothers in Jaipur and Kolkata with irregular cycles longer than 28 days adjust the cycle-length input to get a more accurate EDD than the standard Naegele formula provides.

Husbands and family members in Pune use the tool to plan grandparent visits, Godh Bharai ceremony in the 7th month, and arrange a doula or hospital bag at 36 weeks.

Tips for Pregnancy Planning

Smart Pregnancy Planning Tips

Confirm EDD with a first-trimester ultrasound between 8-12 weeks. CRL-based dating is more accurate than LMP-based dating, especially if your cycles are irregular or you do not remember the LMP date precisely.

Schedule your antenatal check-ups at the standard intervals: monthly until 28 weeks, fortnightly from 28-36 weeks, and weekly from 36 weeks onwards. Government hospitals follow the same MoHFW protocol.

Start prenatal vitamins with folic acid 400-800 mcg daily ideally before conception. Iron and calcium supplements are added from the 2nd trimester. Most Indian OB-GYNs prescribe Folic-9 or similar combinations.

Apply for maternity leave 60 days before EDD if you are salaried. Under the Maternity Benefit (Amendment) Act 2017, you get 26 weeks paid leave for the first two children and 12 weeks for subsequent ones.

Track key scan milestones: NT scan at 11-13 weeks for Down's screening, anomaly scan at 18-22 weeks, and GTT (glucose tolerance test) at 24-28 weeks for gestational diabetes which affects 1 in 5 Indian pregnancies.

Formula Explanation

Core Due Date Formula

EDD = LMP + 280 days (Naegele's Rule)

EDD = Conception_Date + 266 days

Current_Week = (Today - LMP) / 7 (rounded down)

Where:

• LMP = first day of Last Menstrual Period
• • 280 days = 40 weeks = standard human gestation
• • Cycle adjustment: add (cycle_length - 28) days if cycle is longer than 28

Example: If your LMP is January 1, 2026, your EDD is October 8, 2026 (January 1 + 280 days). If today is May 1, 2026, you are at week 17, in the 2nd trimester, with 23 weeks remaining.

Pregnancy Trimester Quick Reference Table

Trimester	Weeks	Key Milestones	Recommended Scan
First	1-12	Folic acid, NT scan	NT/dating scan
Second	13-27	Anomaly scan, GTT, Tdap	TIFFA at 18-22w
Third	28-40	Growth scan, fetal monitoring	Doppler at 32-34w
Term	37-40	Hospital bag, delivery	Pre-delivery USG

Real-World Example

Example: Neha's Due Date Calculation

Meet Neha, 28, a software developer from Bengaluru working at an MNC. She and her husband confirmed her pregnancy with a positive beta hCG of 2,400 mIU/mL on January 25, 2026, and want to plan her 26-week maternity leave.

Step 1: Neha enters her LMP date of December 18, 2025, with a regular 28-day cycle. The calculator computes EDD = September 24, 2026.

Step 2: As of January 25, she is at week 5 day 4 of pregnancy, well within the first trimester. She schedules her dating scan for week 8, between February 12-15.

Step 3: She works backward 60 days from EDD to identify her maternity leave application deadline: July 26, 2026. Her HR portal also calculates expected leave end date as March 25, 2027, factoring in 26 weeks paid plus optional extension.

Result: Neha plans her TIFFA scan for April 25, GTT for June 20, and hospital pre-booking at Cloudnine Bellandur by July 1. She also schedules her Godh Bharai for July 18, exactly in her 7th month.

Frequently Asked Questions About Pregnancy Due Dates

Indian expectant mothers often ask about accuracy of LMP versus ultrasound dating, how irregular cycles affect EDD, what changes for IVF pregnancies, when to start maternity leave under Indian labour law, and what to expect at each trimester scan. The FAQ below addresses each with current MoHFW guidelines, FOGSI recommendations, and practical tips for Indian healthcare settings.