Due Date Calculator
This calculator can be used by entering either your last menstrual cycle date or the date you were conceived and average length of your menstrual cycle. That’s all! The pregnancy calculator will do the rest!
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How do I calculate my due date?
There are many ways to do this. You can use 38 weeks to determine your due date if you know the date you were conceived. (Human gestation lasts about 38 weeks).
Many expectant mothers don’t know when their baby was born. Even if you had only one sex session during your fertile periods, it is unlikely that you would conceive on that day unless ovulating. Your fallopian tubes can store sperm for up to five consecutive days. It could take up to five days for you to release an egg (ovulate). Then, a waiting sperm fertilizes it . This is the day that you conceive.
How can anyone know the date of conception?
Your first day of your last period
The best way to determine your due date for pregnancy is to count 40 weeks from your last period (LMP). This is how healthcare providers usually do it.
Your menstrual cycle should be approximately two weeks longer than the average (28-day) cycle. Pregnancies last for 40 weeks, instead of 38.
This doesn’t account for how long your menstrual period is, or the time you believe you may have conceived. However, women usually ovulate around two weeks after the start of their menstrual cycle. Women are more likely than men to know the date of their last period.
If you know when you conceived , such as if you used an ovulation prediction kit or tracking ovulation symptoms, you can calculate your due date for pregnancy based on the date of conception. Simply choose the calculation method you prefer from the pulldown and enter your date.
You don’t necessarily have to conceive the same day that you have sex. For a great read, check out our stories of parents who remember when and where the act that led to their child.
IVF transfer date
If you were conceived using IVF you can use your IVF transfer date to calculate your due date. You can count 261 days starting from the date of your Day 5 embryo transfer. If you had an embryo transfer on Day 3, count 263 days.
Can my due date change?
If your healthcare provider finds that your baby’s gestational age is significantly different from what you expected, they may revise your due dates. If your menstrual cycle is irregular, it’s more likely that this will happen.
To determine how far along your baby’s development, your healthcare provider will take a measurement of your baby at the ultrasound and give you a new due date.
What if I already know my due date?
This calculator can be used to calculate your due date. This calculator will show you the milestones you’ll reach, such as when your baby’s heart beats and when you might need prenatal care and prenatal testing. It will also tell you what your baby’s sign, birthstone and famous people were born on your due day.
What is my likelihood of giving birth on my due day?
A due date calculation is always approximate. It can be derived from our tool , or from your doctor, midwife, or other sources. Only one in twenty women deliver on their due date. The two weeks preceding and after are equally likely for you to go into labor.