Dr. Shivani on Instagram: "📅 Calculating Your Pregnancy Due Date from Conception (OB-GYN explains) Ever wondered how your pregnancy due date is calculated from conception and not just your last period? Let’s break it down 👇 🔬 Key fact: Pregnancy lasts about 266 days (38 weeks) from conception — or 280 days (40 weeks) from the first day of your last menstrual period (LMP). ✅ How to calculate due date from conception If you know your conception or ovulation date: ➡️ Add 38 weeks (266 days) to t