Plain-language explanations
Pregnancy Metrics guides explain how pregnancy dates, weeks, conception, IVF, weight gain, home testing, and ovulation tracking work. They are educational explanations, not a pregnancy record, diagnosis, or substitute for clinical care.
Use this hub when you want to understand how something works or what a result means. Calculators answer “calculate from information I have”; guides explain the model, interpretation limits, and authoritative sources for one topic.
Choose the concept you want to understand. The result points to one primary guide and names the boundary that guide cannot establish.
Choose one option to see the matching path and its most important limit.
This guide finder does not ask for or store pregnancy dates.
Start with the question you are trying to understand. These guides explain a model or evidence boundary; they do not require you to enter a pregnancy date.
Follow one record through EDD, completed weeks and days, trimester milestones, and an around conception estimate while keeping clinical and biological limits clear.
Read the pregnancy dating guide →Understand embryo age at transfer, the 263- and 261-day offsets, fresh and frozen transfer records, and what IVF dating cannot predict.
Read the IVF dating guide →Compare singleton and twin ranges, later-trimester rate context, and the boundary between population guidance and a personal target.
Read the weight-gain guide →Connect one available record to the conclusions it can support, including approximate fertile timing, expected-period context, hCG testing, and early-negative limits.
Read the trying and testing guide →The topics answer different questions and do not carry the same degree of certainty.
| Topic | Starts from | What it explains | Most important limit | Guide |
|---|---|---|---|---|
| Pregnancy dating and timeline | A current recorded EDD, reliable LMP and average cycle, well-supported ovulation, documented fertilization, or dated pregnancy weeks | How one record resolves to an EDD, completed weeks and days, trimester milestones, and an around conception estimate | It cannot establish exact biological timing, fetal health, a guaranteed birth date, or whether an EDD should be changed | Pregnancy Dating and Timeline Guide |
| IVF dating | The transfer date and documented Day-3 or Day-5 embryo age | How embryo age and transfer date produce the IVF due date and pregnancy-calendar age | It cannot predict implantation, IVF success, viability, pregnancy outcome, or exact delivery timing | How IVF Due Dates Are Calculated |
| Pregnancy weight gain | Pre-pregnancy BMI and singleton or twin pregnancy type | Population-level total ranges and later-trimester rate context | A personal target, diagnosis, or fetal-growth assessment | Pregnancy Weight Gain Guidelines |
| Trying, ovulation and pregnancy-test timing | One LMP-and-cycle, expected-period, ovulation, DPO, recent-sex, or observation record | Which cycle, fertile-window, ovulation-sign, expected-period, and test-timing conclusions each record supports | Exact ovulation, conception or implantation, pregnancy probability, diagnosis, or safe days | Trying, Ovulation and Pregnancy Test Timing |
Related concepts do not make the four guide topics interchangeable. Each guide should be interpreted according to the question and evidence it addresses.
You do not need to read every guide. Use the path that matches what you are trying to understand.
Start with the pregnancy calendar, then learn how the due date anchors that calendar.
Use the current recorded due date rather than recalculating or averaging older dates.
IVF dating starts from the embryo-transfer record, not from an ordinary menstrual-cycle estimate.
Start with the published BMI-based ranges, then use the calculator only for transparent reference arithmetic.
Connect cycle estimates, ovulation signs, expected periods, DPO, and home-test timing without turning estimates into confirmation or diagnosis.
Use Methodology for formulas, date-only arithmetic, supported inputs, boundaries, and update rules. Use Editorial and Methodology Review for the real evidence and release process.
Each guide covers one defined topic in depth and links its factual claims to authoritative sources.
Connect due dates, completed weeks and days, trimester milestones, conception estimates, and record provenance in one coherent pregnancy calendar.
Understand Day-3 and Day-5 transfer formulas, pregnancy age on transfer day, fresh and frozen transfer records, and why IVF dating cannot predict implantation or success.
Understand BMI-based singleton and twin gain ranges, later-trimester rate context, and why published ranges are general guidance rather than personal targets.
Connect cycle estimates, ovulation signs, expected periods, hCG timing, early negatives, and recent-sex testing boundaries without treating estimates as biological facts.
Use the homepage calculator selector to start from the date, cycle information, pregnancy record, transfer record, or measurements you already have.
Use the guides on this page. They explain pregnancy dating, weight gain, home testing, and ovulation tracking without asking you to enter calculator inputs.
Methodology documents constants, date-only arithmetic, supported inputs, boundaries, rounding, and update practices.
Editorial and Methodology Review explains source selection, claim review, testing, release checks, and the absence of external clinician certification.
Review the Privacy Notice for data handling and the Medical Disclaimer for the limits of educational calendar tools.
