Go to CalculatorSkip to Main Content
Evidence-based · Peer-reviewed obstetric research

Labor & Birth Articles

Clinical guides on labor timing, delivery probability, and birth preparation, written for expecting parents and birth professionals.

Filter:pregnancy
Latest Article
Illustration for When Does Labor Actually Start? Signs, Stages, and Timing
Featured
pregnancy7 min read

When Does Labor Actually Start? Signs, Stages, and Timing

Labor starts when uterine contractions become regular and cause cervical change. Here's how to tell the difference between false alarms and the real thing.

Read article
All Articles
Illustration for How Accurate Is Your Due Date? What the Research Actually Shows
pregnancy7m

How Accurate Is Your Due Date? What the Research Actually Shows

Only 4-5% of babies arrive on their due date. Here's what the research says about how accurate EDD calculations really are, and what that means for you.

Read
Illustration for First Baby vs Second Baby: How Labor Timing Differs
pregnancy7m

First Baby vs Second Baby: How Labor Timing Differs

Second labors average 3 days earlier and hours shorter than first. Here's what the data shows about how labor timing and duration differ between first and subsequent births.

Read
Illustration for Going Past Your Due Date: What to Expect at 40, 41, and 42 Weeks
pregnancy8m

Going Past Your Due Date: What to Expect at 40, 41, and 42 Weeks

About 50% of first-time mothers deliver after their due date. Here's what "overdue" actually means clinically, what monitoring involves, and when induction is recommended.

Read
Illustration for 7 Signs Labor Is Coming in the Next 48 Hours
pregnancy8m

7 Signs Labor Is Coming in the Next 48 Hours

Bloody show, regular contractions, water breaking, and 4 other signs that labor may start within 48 hours, plus the 5-1-1 rule for when to go to the hospital.

Read
Illustration for What Affects When You Go Into Labor? 6 Key Factors Explained
pregnancy7m

What Affects When You Go Into Labor? 6 Key Factors Explained

Parity, cervical length, BMI, maternal age, fetal sex, and stress all influence labor timing. Here's what the research actually says about each.

Read
Illustration for Induced vs. Spontaneous Labor: Timing, Risks, and What to Expect
pregnancy6m

Induced vs. Spontaneous Labor: Timing, Risks, and What to Expect

ACOG recommends offering induction at 39-41 weeks. Here's how induction works, what the ARRIVE trial found, and how induced labor differs from spontaneous.

Read
Illustration for Labor Probability by Week: The Statistics Behind When Babies Arrive
pregnancy6m

Labor Probability by Week: The Statistics Behind When Babies Arrive

Week 39 is the single busiest delivery week, but 26% of first-time mothers are still pregnant at 40+0. Here's the actual data table, and what it means.

Read
Illustration for Cervical Dilation and Labor Progress: A Plain-Language Guide
pregnancy7m

Cervical Dilation and Labor Progress: A Plain-Language Guide

Dilation from 0 to 6 cm can take days. From 6 to 10 cm typically takes 1-3 hours in active labor. Here's what each number actually means.

Read
Illustration for Third Trimester Prep: What to Do in the Final 4 Weeks
pregnancy7m

Third Trimester Prep: What to Do in the Final 4 Weeks

Weeks 36-40 each have specific tasks: GBS testing, car seat installation, hospital bag, birth plan. Here's the week-by-week checklist with specifics.

Read