🤰 Pregnancy Calculator Suite

Complete pregnancy calculation tools including due date, gestational age, and weight gain tracking. Get accurate pregnancy information with trimester details and important milestones.

Please Note: The Pregnancy Calculator Suite provides general information only and is not a substitute for professional medical advice. Please consult your GP or healthcare provider for personalised guidance about your health.
Calculate Due Date
Enter the first day of your last period
Most women have 28-day cycles, but anywhere from 21-35 days is normal
Calculate Current Gestational Age
Enter the first day of your last period
Leave blank to calculate for today
Pregnancy Weight Gain Calculator
kg
Enter your current weight to see how much you've gained
Enter how many weeks pregnant you are

About Pregnancy Calculations

Due Date Accuracy

Only about 5% of babies are born on their exact due date. Most babies are born within 2 weeks before or after the estimated due date. Full-term pregnancy is considered 37-42 weeks.

Gestational Age

Gestational age is measured from the first day of your last menstrual period, not from conception. This is the standard used by healthcare providers worldwide.

Weight Gain

Recommended weight gain varies based on your pre-pregnancy BMI. Gaining the right amount of weight supports your baby's development and your health.

Frequently Asked Questions

Due date calculations provide an estimate, but only about 5% of babies are born on their exact due date. Here's what affects accuracy:

  • Method used: Ultrasound dating is most accurate, especially in early pregnancy
  • Timing: First trimester ultrasounds are more accurate than later ones
  • Individual variation: Cycle length, ovulation timing, and individual factors vary
  • Normal range: Full-term babies can be born anywhere from 37-42 weeks

Most babies (90%) are born within 2 weeks of their due date. Your healthcare provider may adjust your due date based on ultrasound measurements.

If you can't remember your LMP, there are other ways to estimate your due date:

  • Early ultrasound: Most accurate method, especially before 12 weeks
  • Conception date: If you know when you conceived
  • IVF dates: If you had fertility treatments, transfer dates are very accurate
  • Physical exam: Your healthcare provider can estimate based on uterus size

Don't worry - this is common! Your healthcare provider will use the most reliable information available to give you an accurate due date.

Healthy weight gain depends on your pre-pregnancy BMI:

  • Underweight (BMI <18.5): 28-40 lbs (12.7-18.1 kg)
  • Normal weight (BMI 18.5-24.9): 25-35 lbs (11.3-15.9 kg)
  • Overweight (BMI 25-29.9): 15-25 lbs (6.8-11.3 kg)
  • Obese (BMI ≥30): 11-20 lbs (5.0-9.1 kg)

Timeline:

  • First trimester: 1-4 lbs total
  • Second/third trimester: 1-2 lbs per week

Remember, these are guidelines. Your healthcare provider will monitor your individual progress and advise if adjustments are needed.

Disclaimer

This calculator is provided for educational and informational purposes only. It is not intended to be a substitute for professional medical advice, diagnosis, or treatment.

  • Always seek the advice of a qualified healthcare provider with any questions regarding a medical condition.
  • Never disregard professional medical advice or delay seeking it because of information from this tool.
  • Clinical decision-making should always incorporate the full clinical context, patient preferences, and local protocols.
  • The creators of this tool accept no liability for decisions made based on its output.

If you are a patient: please discuss any results with your healthcare provider. This tool is designed for use by medical professionals and may not be appropriate for self-assessment.