Guides
General, non-diagnostic background on the ideas behind each calculator, written for when you want the explanation, not just the number. None of this is medical advice; see our Terms of Use for the full disclaimer.
Aug 10, 2026
How your due date is actually calculated (and why it's an estimate, not a deadline)
What Naegele's rule actually does, why it assumes a 28-day cycle, and why most babies aren't born on their exact due date.
Aug 14, 2026
Trimesters explained: where each one actually starts and ends
The standard three-trimester division, why week boundaries vary slightly by source, and a general, non-diagnostic overview of each stage.
Aug 17, 2026
Kick counting: what's normal, and when to call your doctor
Why fetal movement counting is commonly recommended, one general method providers cite, and why a noticeable decrease in movement is always worth a prompt call.
Aug 20, 2026
Timing contractions: what the numbers actually mean
What duration and frequency actually measure, a commonly cited general labor pattern, and the general difference between Braxton Hicks and labor contractions.
Sep 24, 2026
Pregnancy weeks to months: how the counting actually works
Why pregnancy is dated from your last period, how to read weeks and days, a weeks-to-months chart, and the official term definitions.
Sep 24, 2026
The fertile window: how ovulation timing determines conception
How long eggs and sperm survive, why the fertile window is about six days, why ovulation isn't always on day 14, and the signs that help pinpoint it.
Sep 24, 2026
How to choose a baby name: practical checks before you decide
Saying it out loud, initials and nicknames, spelling, meaning, popularity, and sibling names: a practical checklist for choosing a name you'll love.
Sep 24, 2026
Early term, full term, late term: what the definitions mean
The official definitions for preterm, early term, full term, late term, and post-term births, why they changed in 2013, and why the final weeks matter.