Guides
Gestational Age Calculator — Due Date, Conception & Implantation
Step-by-step how-to guides for using Gestational Age Calculator — Due Date, Conception & Implantation and related techniques. Written for practical use — follow each guide to get accurate results for your specific situation.
Twin & Multiples Due Date: Why They Arrive Earlier
How due date math works for twin, triplet, and higher-order pregnancies, and why the average delivery week shortens as the number of babies increases.
beginner Read guide →Week-by-Week Pregnancy Guide: Trimesters & What Gestational Age Means
How the three trimesters map to gestational age in weeks, and how to use a running weeks-and-days count to know exactly where a pregnancy stands.
beginner Read guide →