Pregnancy Due Date Calculator

Use our Pregnancy Due Date Calculator to find your estimated due date and see major milestones throughout pregnancy

 

Select first day of your last period *





Frequently Asked Questions about Pregnancy Due Date Calculator


What is a Pregnancy Due Date Calculator?

A Pregnancy Due Date Calculator is a tool that estimates the expected date of delivery (EDD) for a pregnancy based on the first day of a woman's last menstrual period (LMP) or the date of conception. It helps expectant mothers and healthcare providers plan for childbirth.

How does a Pregnancy Due Date Calculator work?

These calculators work by using a formula that considers the length of a woman's menstrual cycle and the date of her last period. It estimates when ovulation is likely to occur and, subsequently, when the baby is expected to be born, typically 280 days (or 40 weeks) from the first day of the last period.

Why is due date calculated from last period?

LMP is the first day of your bleeding during the last menstrual period. You bleed as the uterus sheds the lining formed during the previous cycle. Ovulation occurs around two weeks from LMP, and that is when you become fertile. If fertilization occurs during this cycle, the uterine lining (endometrium) grows to accommodate the baby, thus making you miss your next period. LMP is also considered for calculation because the date is easier to remember!

How accurate are pregnancy due date calculators?

Pregnancy due date calculators provide estimates that are generally accurate within a range of two weeks. However, the actual delivery date can vary based on individual factors and the accuracy of the input data. It's important to remember that it's an estimation, not a guarantee.

When should I use a Pregnancy Due Date Calculator?

You can use a Pregnancy Due Date Calculator as soon as you know the date of your last menstrual period (LMP) or have information about the date of conception. It's typically used early in pregnancy to give you a rough idea of when your baby might arrive.

How important is knowing my due date during pregnancy?

Knowing your due date is essential for prenatal care planning. It helps healthcare providers monitor the progress of your pregnancy, schedule necessary tests, and ensure you receive the appropriate care leading up to childbirth.

Can I calculate my due date at home, or should I consult a healthcare provider?

You can use online Pregnancy Due Date Calculators at home to get a preliminary estimate. However, it's crucial to consult with a healthcare provider for confirmation and to discuss any concerns or questions you have about your pregnancy.

Does due date calculators predict the exact day of delivery?

No, a due date calculator cannot predict the exact day of delivery. It provides an estimate based on the average length of a full-term pregnancy, which is around 40 weeks from the first day of the last menstrual period. However, the actual delivery date can vary.

Is it possible for my due date to change during pregnancy?

Yes, due dates can change as pregnancy progresses. This might happen if additional information becomes available, such as through an ultrasound examination. Your healthcare provider will let you know if any adjustments to your due date are needed.

Can a due date calculator work for women with irregular periods?

Due date calculators may be less accurate for women with irregular periods. If you have irregular cycles or are unsure of your last menstrual period, it is recommended to consult with a healthcare provider for a more accurate estimate. They can consider additional factors to provide a personalized calculation.

C-Section and Due Date Calculator

In the event of a C-section delivery, whether it is a planned C-section or an emergency C-section delivery, using a pregnancy calculator can still be extremely beneficial. The milestones provided by the calculator remain valid and useful in tracking the progress of your pregnancy. However, it's important to note that the exact date of your C-section will be determined by your healthcare provider, who will take into consideration your specific medical conditions and circumstances. Most elective C-sections are typically scheduled near full term, which is around 39 to 40 weeks of gestation.

Should I rely solely on a due date calculator for determining my due date?

It's always best to consult with a healthcare provider to determine your due date accurately. They can consider various factors, such as ultrasound measurements and other medical information, to provide a more precise estimate tailored to your specific circumstances.

Can a due date calculator determine the gender of my baby?

No, a due date calculator cannot determine the gender of your baby. Its purpose is solely to estimate the expected due date based on the provided information. Determining the gender requires other methods, such as ultrasound or genetic testing.

What if the estimated due date from the calculator does not match my ultrasound measurements?

Ultrasound measurements are considered more accurate for estimating the due date. If there is a significant difference between the estimated due date from the calculator and the ultrasound measurements, your healthcare provider will use the ultrasound information as a more reliable reference.

Can I use a due date calculator if I have had fertility treatments or IVF?

If you have undergone fertility treatments or in vitro fertilization (IVF), the conception date may not align with the date of your last menstrual period. It is best to consult with your fertility specialist or healthcare provider for an accurate due date estimation tailored to your specific circumstances. Dedicated online IVF due date calculators are also available.

Are there any other factors that can affect the accuracy of a due date calculator?

Certain factors, such as maternal age, maternal health conditions, irregular periods, and variations in fetal development, can affect the accuracy of due date calculators. These tools provide estimates based on averages and may not account for individual variations. Consulting with a healthcare provider can help address these factors.

Can I still use a due date calculator if I don't know the exact date of my last menstrual period?

If you don't know the exact date of your last menstrual period, it is recommended to consult with a healthcare provider who can help you estimate your due date based on other information, such as the date of conception or ultrasound measurements. They can use alternative methods to provide a more accurate estimate.

What if my calculated due date passes, and I haven't gone into labor?

It's relatively common for pregnancies to go beyond the estimated due date. Your healthcare provider will monitor your progress and may recommend induction or other interventions if necessary to ensure a safe delivery.

Reviewed By

Dr Sobia Mohyuddin

MCPS, FCPS, MRCOG, Consultant Obstetrics & Gynaecology

Doctor Sobia Mohyuddin is a highly skilled and experienced Obstetrician and Gynecologist, with 25 years of training and experience in renowned, large institutions. She holds the position of Associate Professor and Fellow at the College of Physicians and Surgeons Pakistan. She is also a member of the Royal College of Obstetricians and Gynecologists (UK).