Due date calculator for pregnancy - Purely Fertility
Due Date Calculator
Enter the first day of your last menstrual period (LMP) to estimate your due date and see your pregnancy timeline unfold.
Your Pregnancy Timeline
Estimated Due Date
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This is an estimate based on your LMP. A first-trimester ultrasound is the most accurate method for dating a pregnancy.
Your Due Date is an Estimate.
The Estimated Due Date (EDD) is the anchor of your pregnancy journey, but it's also the center of a paradox. While we circle a single day on our calendars, the science tells a different story. This guide is here to empower you with a deeper, evidence-based understanding of your unique pregnancy timeline.
The 4% Reality
Overwhelming evidence shows that only about 4-5% of babies are born on their exact due date. This single statistic changes everything. It reframes the EDD not as a deadline, but as the midpoint of a wide, normal range of birth timings. Let's explore what that means for you.
How Is My Due Date Calculated?
The journey to your EDD begins with a calculation, but not all methods are created equal. Understanding the different approaches and their accuracy is the first step to becoming an informed partner in your own prenatal care.
When Will My Baby *Really* Arrive?
Let's replace the idea of a "due date" with a "due window." A full-term pregnancy spans five weeks, and understanding this distribution is key to managing expectations and reducing anxiety.
This chart shows the likelihood of giving birth in any given week. Notice how the peak shifts based on birth history. Your EDD is simply the middle of this curve.
Your 40-Week Journey
Your EDD is the master key for your entire prenatal care schedule. It dictates the timing of crucial visits and tests that monitor your health and your baby's development. Explore the typical timeline for a low-risk pregnancy.
Navigating The Wait
The days after your due date can be emotionally challenging. Knowledge and preparation are your best tools. Here's what to expect if the clock keeps ticking, and how to manage the emotional landscape.
The Clinical Plan After 40 Weeks
When your pregnancy extends into the late-term window (41+ weeks), your care team initiates a standard, evidence-based plan to ensure both you and your baby remain healthy. This is a routine and proactive process.
Confirm the Date
Your provider first re-confirms the accuracy of your EDD, ensuring it was based on a reliable first-trimester ultrasound.
Increase Fetal Surveillance
Starting at 41 weeks, you'll likely have more frequent monitoring (1-2 times per week), such as Nonstress Tests (NSTs) and Biophysical Profiles (BPPs) to check on baby's well-being.
Discuss Induction
Your provider will discuss inducing labor. This is a standard recommendation after 41 weeks to reduce the small but increasing risks associated with a post-term pregnancy.
Coping Strategies for the "Overdue" Limbo
It's normal to feel impatient and anxious. Focus on what you can control and be kind to yourself during this final phase of waiting.
- ✓ Reframe the Narrative: Actively use the term "due window." A birth at 41 weeks is just as normal and "on time" as one at 39 weeks.
- ✓ Plan for the Wait: Fill your days with gentle, enjoyable activities. A favorite meal, a movie, a slow walk. This avoids feeling stuck in a void.
- ✓ Manage Communications: Prepare a polite, standard text response for well-meaning inquiries. This saves you emotional energy.
- ✓ Talk to Your Provider: Share your feelings of anxiety. Understanding the monitoring plan can be incredibly reassuring.