Reviewed by Dr. Sony Sherpa, MBBS, MD on Dec 22, 2025 Estimate your likelihood of twins based on age, family history (maternal side), height/BMI, ethnicity, prior pregnancies, fertility treatment, and past twins. Results show a baseline risk with a fraternal (dizygotic) vs identical (monozygotic) split, using population studies. Basics Female age Prior births Family history … Continue reading Chance of Twins Calculator