Medical Review & Content Methodology
How We Ensure Information Accuracy
Every piece of medical content on this site passes through three stages: drafting from accredited medical sources (guidelines from the American College of Obstetricians and Gynecologists ACOG, the World Health Organization, and the Saudi Ministry of Health), then review of calculation accuracy (Naegele's rule, the Mifflin-St Jeor equation, Institute of Medicine IOM ranges), then periodic updates (every page carries a last-reviewed date).
The Calculations We Use
Due date: Naegele's rule (LMP + 280 days); the global medical standard.
Hijri conversion: the tabular (calculated) Hijri calendar; approximate, within +/- 2 days of the official calendar.
Ovulation: a 14-day luteal phase before the next period.
Weight gain: the American Institute of Medicine ranges (IOM 2009).
Calories: the Mifflin-St Jeor equation multiplied by an activity factor.
The Limits of Our Responsibility
The calculators are guidance tools and do not replace your doctor. Every pregnancy is a special case; keep up with your doctor's scheduled appointments.