Pregnancy Dating Explained: Due Dates, Weeks & Conception
Start with why pregnancy starts before conception, then see how weeks are counted and why last-period and ultrasound dates may differ.
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Pregnancy & Preconception Blog
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How IVF Due Dates Are Calculated
Learn how documented Day-3 or Day-5 embryo age and transfer date relate to an estimated due date for fresh or frozen transfers.
Pregnancy Weight Gain Guidelines
Understand published singleton and twin ranges by pre-pregnancy BMI, and why population guidance is not a personal target.
Trying, Ovulation and Pregnancy Test Timing
Connect cycle estimates, ovulation signs, expected periods, early negatives and recent-sex timing without treating an estimate as confirmation.
For the underlying formulas and source references, see the Methodology. The Editorial and Methodology Review explains how site content is checked and maintained.