The Lowdown On Due Dates

If you're reading this, chances are you're wondering about that exciting date circled on your calendar: the day you’re expecting to welcome your little one into the world! But will your baby actually arrive on that specific day? Why or why not? 

The truth is, your estimated due date is exactly that: an estimate, not a deadline. In fact, according to the Cleveland Clinic, only around 4% of babies actually arrive on their exact estimated due date.

In this blog, we're going to break down everything you need to know about due dates. We'll explain how they're calculated, what they really mean, and why your baby might decide to be fashionably early or fascinatingly (even frustratingly!) late.

In fact, here’s a calculator you can use!

Let’s break down this due date calculator and the method behind it: 

Your last menstrual period, or LMP, is exactly what it sounds like—the first day of your last period before you got pregnant. From that period date, we add 280 days, which is about 40 weeks. And that’s that! You've got your estimated due date.

This pregnancy due date calculator method assumes a few things:

1. You have a regular 28-day menstrual cycle
2. You ovulated on day 14 of that cycle
3. Conception occurred shortly after ovulation

Of course, we know that not every woman's body follows this exact schedule. That's why it's called an estimated due date. Your healthcare provider uses this as a starting point, but they might adjust it based on other factors.

That said, while the LMP method is common, it's not the only way to determine your due date. Here are a few other methods your healthcare provider might use:

This calculation method is especially useful if you're not sure about your LMP, conception date, or if your cycles are irregular. An early ultrasound scan (usually done between 6-12 weeks) can give a pretty accurate estimate of how far along you are.

If you know exactly when you conceived (like if you’ve used IVF and know your IVF transfer date), your healthcare provider can use that date of conception to calculate your estimated due date.

Remember, no matter which calculation method is used, your due date is always an educated guess. Your baby is on their own schedule, and they'll come when they're good and ready no matter what any due date calculator says—although we understand if you're ready way before they are!

In the next section, we'll dive deeper into what your due date really means and why it's so rare for babies to actually arrive on that exact day.

Okay, mama, now that we know how your due date is calculated, what does it really mean?

Well, remember that 4% statistic we mentioned earlier? This tells us your due date is actually more of a "due month" rather than a specific day. Instead of thinking of your due date as a deadline, consider it the middle of a range of time when your baby is likely to arrive.

In the medical world, we talk about "term" pregnancies. Here's a quick breakdown:

• Early Term: 37 weeks to 38 weeks and 6 days
• Full Term: 39 weeks to 40 weeks and 6 days
• Late Term: 41 weeks to 41 weeks and 6 days
• Post Term: 42 weeks and beyond

Your due date falls right at the 40-week mark, but as you can see, your baby is considered full-term for about two weeks before and after that estimated date. That's why only about 4% of babies arrive on their exact due date—they have a whole window of time.

Even so, having a due date calculated is helpful for:

1. Tracking your baby's growth and development
2. Scheduling important prenatal tests and check-ups
3. Helping you plan for maternity leave and baby prep

Your body and your baby are working together to determine the best time for birth. Trust the process, but always keep in touch with your healthcare provider about any concerns.

Several factors can influence when your little one decides to make their debut:

The due date calculator equation we shared earlier assumes a regular 28-day menstrual cycle. But if your cycle length is often longer or shorter (or if your cycle length varies), it can affect when you actually ovulated and conceived. As a result, this might mean your due date calculation is a bit off.

Even if you have regular cycles, you might ovulate later than the assumed day 14. This could push your pregnancy due date back a bit, too. 

If you've conceived through IVF or other fertility treatments, your due date might be calculated differently and potentially even more precisely. In these cases, we often know exactly when conception occurred, which can give us a more accurate due date. However, as we’ve said, each person is different and each pregnancy is different. Even with fertility treatments, your due date is still an estimate.

Expecting twins, triplets, or more? Congratulations! Mamas who are carrying multiple babies at the same time often deliver a bit earlier than single pregnancies. Your healthcare provider will adjust your due date accordingly and keep a close eye on you and your little crew.

Interestingly, around 12% of first-time moms deliver babies early, compared to 10% of subsequent pregnancies. Data also shows that among full-term pregnancies, first babies are born about 1.3 days later on average.

Believe it or not, there might be a genetic component to when babies decide to arrive! If your mom or sisters tended to deliver early or late, you might follow a similar pattern.

Sometimes, your baby's position in the womb can affect when labor starts. If your baby is in an optimal position, they might be ready to go right on time. But if they're in a tricky position, they might need a little extra time to maneuver.

Remember, these factors don't determine your exact delivery date—they're just pieces of the puzzle. Your baby will come when they're ready, and that's perfectly okay! The most important thing is to keep in regular contact with your healthcare provider, who can monitor you and your baby's health throughout your pregnancy.

Your due date isn't just about baby prep, deciding when to start your maternity leave, or generally preparing for your postpartum, “4th-trimester” experience (although those are pretty important too. Speaking of, you might want to check out some of our favorite apps for pregnancy and postpartum!). Your due date is a crucial tool for ensuring you and your baby get the best care possible throughout your pregnancy.

Your due date helps your healthcare provider track your baby's growth and development. At each stage, your provider knows what to look for and can ensure your little one is hitting all those important milestones. From the first flutter of a heartbeat to those mighty kicks that keep you up at night, your due date helps put it all in perspective.

Certain tests and screenings are time-sensitive and need to be done at specific points in your pregnancy. Your due date helps your healthcare team schedule these at just the right time. For example:

• First-trimester screening: 11-13 weeks
• Anatomy scan: 18-22 weeks
• Glucose screening: 24-28 weeks

Without an accurate due date, you might miss the window for some of these important checks. And we know you don't want to miss a single glimpse of your adorable new baby! You can learn more about what to ask during your first prenatal appointment in our blog here!

Your due date also helps you and your family prepare for your new arrival. It gives you a timeline for:

• Setting up the nursery
• Packing your hospital bag
• Arranging maternity leave
• Scheduling childbirth classes

Since your due date is not set in stone, your healthcare provider will be monitoring you and your baby throughout your pregnancy and may adjust your care plan as needed. The goal is always the same: a healthy mom and a healthy baby!

Babies, as it turns out, aren't great at reading calendars. Some are eager to meet the world and arrive early, while others need a little extra encouragement. Let's talk about what happens on both ends of the spectrum.

If your little one decides to arrive before 37 weeks, they're considered premature. While it can be scary if your baby comes early, remember that modern medicine has come a long way in caring for preemies. Here are some signs that labor might be starting early:

• Regular contractions
• Lower back pain
• Pelvic pressure
• Changes in vaginal discharge

If you experience any of these before 37 weeks, don't hesitate to call your healthcare provider. They're there to support you and your baby, no matter when labor starts!

On the flip side, what if your due date comes and goes with no sign of baby? First, take a deep breath. Remember, only 4% of babies arrive on their due date, so you're in good company! Here's what you need to know:

• Your healthcare provider will likely schedule extra check-ups to monitor you and baby.
• They might recommend tests to ensure your placenta is still doing its job effectively.
• You might be offered a membrane sweep or other methods to encourage labor to start naturally.

If you reach 41 or 42 weeks, your provider might discuss the option of induction. This is when medications or other techniques are used to kick-start labor. The decision to induce is always made with your and your baby's health in mind. Even so, always ask your healthcare provider any questions you may have, and remember: You are the best advocate for your birthing plan!

Whether early, late, or right on time, here are some signs that your baby might be on their way:

• Regular contractions that increase in intensity
• Water breaking (although it's not always a dramatic gush like in the movies!)
• Bloody show (a pink or brown discharge)
• Nesting instinct (suddenly feeling the urge to clean and organize everything)

Some women experience all these signs, while others only have a few. When in doubt, always reach out to your healthcare provider. They're your best resource for navigating the exciting and sometimes unpredictable journey to meeting your little one!

It's normal to feel a mix of excitement, anxiety, and impatience (and discomfort if baby’s running late)! At this sensitive, life-changing time, try to focus on the positive:

• Each day your baby stays put is a day they're growing stronger
• You're almost there, and soon you'll be holding your little one in your arms
• This is a special time, so try to savor these last moments of pregnancy

And if you're feeling overwhelmed, don't hesitate to reach out to your healthcare provider, a trusted friend, or a support group. Speaking of which, you can find a group of wonderful mamas and soak up some virtual community support in our Facebook group, The Pumping Room!

Remember, mama, every pregnancy is unique, just like every baby. Your journey is your own, and it's all part of the amazing adventure of bringing new life into the world.

As you navigate these final weeks (or days!) of pregnancy, know that you're not alone. Your healthcare provider is there to guide you, and we at Aeroflow Breastpumps are here to support you.

So take a deep breath and get ready for the most amazing job you'll ever have. You've got this, mama, and we're cheering you on every step of the way!