In order to calculate the estimated conception date, the calculator will use the last menstrual period date, date back three months, and then add seven days to determinate your due date. With the estimated delivery date, it will count back 38 weeks to give an approximate date of conception Some women can tell when they ovulate, and this gives them a very good indicator as to when they conceived as well. Women who are in turn with their bodies can notice the subtle changes such as changes in the cervical mucus, heightened sense of smell, breast tenderness, pelvic or lower abdominal pain (some can even tell which side they ovulated from), light spotting, and a heightened sex drive (your body wants you to get pregnant).
When you find out that you’re pregnant, naturally the first thing you want to know is your due date! That is completely normal, since that is the exciting day that you will get to meet your little one! However, your next question might be what day you conceived.
It sounds pretty simple right? Your conception date will be the day you had sex, right? Not so fast… Remember that sperm can live in the body for up to five days, so the day you had sex is not necessarily the date you conceived. Let’s explain how to figure out the date you conceived. Figuring out your date of conception If you have already been to the doctor, and know your expected , figuring out your date of conception is quick and easy!
All you need to do is start with your due date, and count back 266 days. Simple as that! If that sounds like too much work to you, there are also a ton of online conception/due date calculators that will do all the work for you. So, if you know your due date already, it is a snap to figure out your date of conception. However, if you have not seen a doctor yet, and are trying to figure out your date of conception, it might be a little bit harder to figure out.
If you have already been for ovulation purposes, figuring out your date of conception might be a bit easier. If you know when you ovulate, you know that your egg must be fertilized within 24 hours of ovulation, so that can narrow it down quite a bit for you.
Do the math! However, this is how to determine an if you haven’t been tracking your cycles. First of all, determine the date that you started your last period, and mark it down, if you haven’t already.
That is Cycle Day #1. Then add eleven days to the date your last period started. This is the first day that it was possible for you to conceive.
Now, add another ten days to the first day that conception was possible. Those ten days are the days that it is possible for you to have conceived. Again, that is not to say at all that you have 10 days in which you can get pregnant every month. Far from it. You are only fertile for about 2-5 days during an entire cycle. But since for this exercise, you do not know exactly when you ovulate, we will have to allow some wiggle room to do your math.
You will have to narrow it down within those ten days to determine what your actual date of conception was. Remember: conception dates are just estimates Keep in mind, that just like due dates, conception dates are usually just estimates. You can sometimes pinpoint the exact date that you conceived, but not always. At least knowing your estimated date of conception will give you a better idea of when you conceived.
As always, keep in mind that even if you do know your date of conception and your due date, it is no guarantee of when your baby will arrive. Babies come whenever they decide it’s time! Sometimes late, sometimes early – but only 3% come exactly on their due date!
when are my best conception date calculator - When is my ovulation date calculator
When is my baby’s due date? So you got your , you’re feeling some , and now you’re wondering, “when is my baby’s due date?” We’ve got you covered with the Mama Natural due date calculator!
Enter your information in the due date calculator above and discover the best estimate for when your little bundle of joy will make his or her appearance.
How does this due date calculator work? Because you may not know exactly when you ovulated or conceived, a due date calculator will typically calculate your estimated due date based on your last menstrual period (LMP).
Our online due date calculator uses a simple method to calculate your due date. • Your due date is estimated to be 40 weeks after the first day of your LMP • Your cycle is assumed to be 28 days long, with ovulation occurring at day 14 • Therefore the calculator adds 280 days (40 weeks) to your LMP This method of due date calculation is known as (more info on this below). My cycle isn’t 28 days. Will this due date calculator work for me?
Yes. The logic behind our pregnancy calculator works as follows: • The average cycle length is 28 days • If your cycle length is shorter, your due date will be earlier • For every day your cycle is shorter, your due date moves one day earlier • Similarly, if your cycle is longer, your due date will be later • For every day your cycle is longer, your due date moves one day later How do you calculate due date from conception?
If you know when you conceived, our pregnancy calculator calculates your due date by adding 38 weeks to the date of conception.
This method of calculation may be more accurate than a LMP due date calculation if you have irregular or consistently longer or shorter cycles than 28 days. What exactly is the date of conception? The date of conception is the day that the egg and sperm meet.
Women who track their ovulation may know their exact date of conception. But for many women, date of conception can be tricky to pinpoint. Sperm can live in a woman’s body for up to five days, and the ovum (egg) can live for up to 24 hours after being released. In other words, you have a six-day window where you could potentially get pregnant each month. Do you already know your due date but want to know when you likely conceived? Try our . What is an estimated due date (EDD)?
An estimated due date (EDD) is a “best guess” as to when baby might be born based on a due date calculator like this one. However, only 4% of babies are born on their due date!
Whereas 80% of babies are born within the window of two weeks before and two weeks your due date calculator results. (See “due month” section below.) What is “gestational age?” Can it be different than what the calculator shows? Gestational age (GA) is the term used to describe how far along the pregnancy is and how long baby has been gestating (growing in the uterus).
If you get an ultrasound you may notice a “GA” on the image with a number of weeks and days. This figure is based on how the baby is measuring, not on your LMP, which the due date calculator uses.
It’s normal for these dates to not match up perfectly. If there are significant differences in the dates, your doctor may want to dig deeper to determine conception date. As a result, your midwife or doctor may change your due date based on the ultrasound gestational age.
Early ultrasounds are very accurate when dating a pregnancy and can be helpful if you don’t know your LMP or your periods are irregular. Note that you don’t have to have an early ultrasound, especially if you are fairly certain of your cycle length and conception window. shows that early dating ultrasounds don’t change the incidence of . How are the weeks of pregnancy calculated? The 40 weeks of pregnancy begin on the first day of your last menstrual period. This can be a little confusing because, for most people, conception doesn’t occur until day 14 of the menstrual cycle.
So yes, you aren’t actually pregnant during those first two weeks of pregnancy. Here’s a more in-depth answer to that perennial question of What is a “due month?” A “due month” is a more accurate timeframe for when you can expect to deliver your baby. Only 4% of babies are born on their due date. Whereas 80% of babies arrive either two weeks before the due date or two weeks after.
Hence the term “due month.” The length of a natural pregnancy can vary by as much as five weeks. () A due month helps some mamas reduce the stress and fear of going past their due date. To calculate your due month, simply subtract two weeks from your EDD given by your practitioner or our due date calculator and also add two weeks to your EDD.
Voilà, your due month! Yet another way to handle this tricky business of calculating your pregnancy calendar is to add two weeks to the end of your EDD and say, “Baby will likely be here before [that date].” What is Naegele’s rule for due date calculation? Naegele’s rule is what this due date calculator and pregnancy calendar is based on. Named after a German Obstetrician who practiced in the early 1800’s, Naegele’s rule predicts childbirth to occur 280 days afterthe first day of the last menstrual period.
However, Naegele’s rule assumes that your cycle is 28 days long with ovulation occurring on day 14, which isn’t the case for many women. So other ways of calculating your due date may be more accurate. ( Find out in this post.) Modern data suggests that women have their babies a few days after their due date on average. Studies like found that Naegele’s rule consistently places the due date about 2-4 days too early. So a better estimate may be 40 weeks and 3 days from LMP.
Alternatively, you can use our , which uses the Mittendorf-Williams rule to calculate your due date. What’s the Mittendorf-Williams rule? done in 1990 showed that pregnancy lasted an average of 288 days past LMP for Caucasian first-time moms. For Caucasian women who were no tfirst-time moms, their date of delivery averaged 283 days past LMP (3 days after Naegele’s rule predicted).
This finding is known as the Mittendorf-Williams rule. While Naegele’s rule is still the most widely used formula for a due date calculator, the Mittendorf-Williams rule is proving to be more accurate. But it’s a much more complex calculation, taking into account: • Maternal age • Race • Height • Weight • Number of pregnancies • Average luteal phase length • Maternal education • Alcohol during pregnancy • Our uses the Mittendorf-Williams rule.
Related Resources • 📅 • 📘 • ◀️ • 👶🏼 • ✅ Ready to calculate your due date?
As soon as you get a positive , the first thing you probably want to do is type “conception calculator” or “When did I conceive?” into Google. And if you do, you’ll find loads of online calculators that promise to give you your conception date.
But the truth is that online calculators (which use formulas) will only give you an estimate of your conception date. Before we dive into understanding the complex process of conception, let’s take a look at how these conception calculators typically work. When you’re trying to determine when your pregnancy began, the date you’re really looking for is —when the fertilized egg burrowed into your uterine lining, thereby beginning your pregnancy.
You can figure out this date using a couple of simple formulas (which we’ve also covered in our post). If you know the date you ovulated, add 9* days. Ovulation date + 9 days = Implantation date If you know the first day of your last menstrual period (LMP), add 23** days. Date of LMP + 23 days = Implantation date *The average viable embryo implants at 9 days post ovulation. **14 (the average number of days between LMP and ovulation ) + 9 (the average number of days between ovulation and implantation) = 23 days.
Again, it’s important to note that the above formulas are just a rough guess based on when ovulation and implantation tend to happen on average for most women. For accurate information about your specific fertile window, is really helpful. When did I conceive? If you’re trying to figure out when conception occurred, it’s important to know that conception isn’t the whole story of when your pregnancy began.
Rather, it’s a two-part process that includes both conception (fertilization of the egg after ) as well as . What is ovulation? During the follicular phase—the first half of your cycle—the fluid-filled sacs in your ovaries (follicles) that contain immature eggs will grow. One follicle will become dominant and begin secreting estradiol, which will cause a surge in luteinizing hormone (LH). This surge ruptures the follicle, releasing a mature egg, which then begins traveling through the fallopian tubes that connect the ovaries to the uterus.
The resulting egg release—triggered by the LH surge—is called ovulation. If you’re wondering , it varies for each woman, but on average, it happens around 14 days after the beginning of your period. (But again: cycle tracking will show you more precisely when you ovulate, instead of using a formula to arrive at an estimate.) Once an egg is released, it must be fertilized within 12 – 24 hours, or the egg will no longer be viable.
The healthiest sperm can remain viable inside a woman’s body up to five days when fertile cervical mucus is present. Since the window of fertility is quite short, using an , or maintaining an up-to-date ovulation calendar or can help you keep track of the .
(The short answer? Have sex two to three days before you ovulate!) Finally, the now-fertilized egg must complete its journey to the uterus and implant in the uterine wall. Implantation generally occurs between 8 – 10 days after ovulation. If any of these steps fail, the egg will die and be excreted during your next period, and the ovulation process will begin again for the next month. When is my due date?
Once you’ve confirmed that you’re pregnant, of course, you’ll want to know when you can expect your baby’s arrival. Knowing your conception date helps with . More importantly, showed that having an accurate due date positively effects pregnancy outcomes, as it allows doctors to make better decisions, such as whether or not to induce labor. (Also, check out our post on figuring out you are.) Traditionally, your estimated due date (EDD) is determined by adding 280 days to the first day of your last menstrual period (LMP).
However, this practice assumes your menstrual cycle is 28 days long, and that ovulation occurs on the 14 th day after your period begins. Many women, however, do not operate on this cycle. Using the 28/14 model doesn’t account for irregularities in your , not knowing the exact date of your LMP, or variability in ovulation timing.
How accurate are conception calculators? Conception calculators and due date calculators are great for providing a ballpark due date. But it’s important to remember these rough estimates don’t take the variability of your cycle into account. When determining a fetus’s gestational age, doctors can utilize several different diagnostic methods. Perhaps the most ubiquitous involves using . Other methods include dating the pregnancy from the LH surge, which happens just before ovulation; , which is released into your body only once an egg successfully implants in the uterus; and during first- and second-trimester ultrasounds.
Are online conception calculators different from the “wheel” one that my doctor uses? When you visit your doctor to discuss your pregnancy, they may use a gestational calculator called a pregnancy wheel. Like many conception calculators, the pregnancy wheel uses the date of your LMP. By shifting one layer of the wheel to the appropriate LMP date, other notable dates (like your possible due date) are revealed. The information provided by the pregnancy wheel and conception calendars is the same.
However, while a pregnancy wheel helps to determine your EDD, it also provides additional information about the various stages of pregnancy, such as the estimated weight of the fetus and the optimal windows for various types of prenatal screening. A few years ago, The American College of Obstetricians and Gynecologists reinvented the pregnancy wheel as , and now encourages the use of this app in place of the older physical, plastic wheel.
Why is my calculated due date different from the one on my ultrasound? A conception calendar uses the date of your LMP to calculate your estimated due date. An ultrasound, however, determines the estimated gestational age of an embryo or fetus by taking biometric measurements. Usually, this involves measuring the (CRL) of the embryo or fetus. In the first trimester, embryo sizes are pretty consistent.
Thus, by comparing the observed size of your embryo or fetus to the established norm, it is possible to determine its gestational age more accurately. According to the of the Society of Obstetricians and Gynaecologists of Canada, the due date derived from ultrasound is the best one for clinical use. (But it won’t tell you the exact date of conception because of factors such as biological variability in reproduction, fetal size, and development.) Can a conception calculator be wrong?
As much as you’d love to know the exact timing of conception (and, consequently, your EDD), conception calculators can be wrong because of the amount of estimation involved. Having an irregular cycle, a longer or shorter than average follicular phase, or an early or late implantation date can all affect your due date. published in the International Journal of Gynecology & Obstetrics found that only 5% of women actually gave birth on their EDD, regardless of the dating method, while 66% of births occurred within a week of their EDD.
Ovulation calculator - your own fertility days calculator & calendar