Natural Pregnancy Calculator
How Does This Natural Pregnancy Calculator Work?
Developed at Erasmus University Medical Centre, Rotterdam (2004), this calculator uses five clinical factors to calculate the likelihood of spontaneous pregnancy leading to a live birth — without fertility treatment. At Bavishi Fertility Institute, specialists use this score to decide between expectant management, IUI, or direct IVF.
Step 1 — Your Age & Duration
These are the two strongest predictors in this natural pregnancy calculator.
About This Calculator
Why Patients Use This Calculator
Built for patients who need real numbers — not just hope.
Know Where You Stand — Right Now
Stop guessing. Your natural pregnancy probability is calculated instantly based on validated clinical data.
Reduce Anxiety & Uncertainty
Knowing your actual probability — even if it's lower than hoped — is less distressing than not knowing at all.
Stop Waiting — Start Acting
A low score removes the temptation to 'just try a few more months' when time is your most valuable resource.
Walk Into Your Consultation Prepared
Share your probability score with your specialist to have a more focused, productive first appointment.
Make Smarter Financial Decisions
Knowing whether IUI or IVF is appropriate first helps you avoid spending months on ineffective treatment.
A Tool Loved by Your Own Doctor
The Hunault model is the same tool used by fertility specialists at Bavishi and leading clinics worldwide.
Before using this calculator, we had been trying for 2 years with no direction. Seeing our score was the push we needed to book a consultation. Three months later, we were pregnant through IUI.
Who Should Use This Calculator?
Couples trying 6+ months
If you've been trying for 6 months or more without success, it's time to understand your probability.
Women aged 35–40 planning a pregnancy
Age is the strongest predictor — understanding your score motivates acting at the right time.
Couples with a known semen report
Sperm motility is a key input — use your semen analysis result to get a more accurate score.
Unexplained infertility
When no cause is found, this model helps guide whether expectant management or treatment is better.
Considering IUI or IVF
Use your score to understand whether IUI is appropriate first or if IVF is the better path.
After initial fertility investigations
Integrate your test results into a probability score before deciding on your treatment pathway.
Fertility Calculators To Plan Your Pregnancy Journey
Use our expert-designed fertility calculators to estimate IVF success rates, track ovulation, understand your fertile window, and plan your journey to parenthood with confidence.
Find a Bavishi Fertility Institute Centre near you.
14 centres across 8 cities — premium fertility care, close to home wherever you are.