Hello glorious Bold Birthers!

So, here we are! You’ve had your ‘check-in’ appointment, given them the first day of your last period (if you knew when that was!) and received this tangible estimated due date that’s immediately stuck in your diary like an appointment for “Busy – baby born on this day” and then booking nothing in for a few weeks afterwards – right?

Bringing new life into this world is a remarkable journey filled with anticipation, excitement, but also apprehension. And aside from that first positive pregnancy test, one of the most pivotal moments is the determination of your estimated due date (EDD). This date serves as a reference point, helping both you and your chosen healthcare providers track the progression of your pregnancy.  This blog delves into the intricacies of estimated due dates, exploring how they are calculated, factors that influence accuracy, and the importance of embracing flexibility as that date approaches.

The Science Bit:

The estimation of a due date involves a combination of factors, primarily relying on the first day of the last menstrual period (LMP) and the average length of a menstrual cycle. Traditional methods, such as Franz Naegele’s Rule, calculate the EDD by adding 280 days (40 weeks) to the first day of your LMP. However, with technology advancements, hospitals now use ultrasound measurements to enhance the date accuracy.
This can be especially useful because this calculation arrived in the 1800s and makes A LOT of glorious assumptions (like every woman ovulating every 14 days etc), so you can imagine things have changed somewhat since then… (it also turns out that ole Franz wasn’t too great at note taking so we’re not 100% sure if he actually meant first day of LMP or another time… 😬)

Ultrasounds, typically in the first trimester, allow sonographers to measure the crown-rump length (head tip to buttocks) of the foetus, providing a more precise estimate of gestational age. This method is particularly helpful if you have irregular menstrual cycles or not sure when your last period was.

Factors Influencing Estimated Due Date Accuracy:

While healthcare providers strive to give accurate estimated due dates, it’s important to know that several factors can massively impact their predictions:

1. Individual Variability: You are unique and an individual, therefore foetal development can vary. Some babies may grow faster or slower than average, leading to slight variations in gestational age.
2. Cycle Irregularities: If you have irregular menstrual cycles you may find it challenging to pinpoint the exact date of conception, which means it can make it more difficult to calculate dates.
3. Late Ovulation: If you conceived later in your menstrual cycle the estimated due date may not align with traditional calculations.
4. Medical Conditions: Certain medical conditions, such as polycystic ovary syndrome (PCOS), can impact menstrual regularity and affect due date accuracies too.
5. Ethnicity: Certain ethnic groups have shown shorter gestational lengths. For example, a few studies have shown an average 5 days shorter in Black and Asian pregnancies, so keep researching!

A fascinating thang:

Did you know that there is no worldwide universal agreement as to when a human baby is due?  In America, we’re dated around 37 weeks (hello sky rocketed induction and c-section rates), here in the UK we’re 40 weeks (and yes our induction and c-section aren’t much better than our USA neighbours), in France it’s 41 weeks (yep their stats are much lower and more accurate), and in some countries we’re provided an entire month to give birth in… 🤷🏻‍♀️

The Importance of Flexibility:

It’s crucial for you to approach your estimated due date with a sense of flexibility. Only about 5% of babies are born on their due dates, and the majority arrive within a two-week window around the EDD. Factors such as natural variations in pregnancy length, spontaneous labour onset, and medical interventions can influence the actual birth date.

Being mentally prepared for the possibility of a later arrival can help reduce stress and anxiety as the date approaches. And understanding that the key word here is ESTIMATED due date, not an exact science, so you can focus on your health and well-being rather than fixating on a specific date.

You can see what some of my followers said about their due dates too:

Top Tip!

When telling others when your estimated due date is, add two weeks to it OR provide the following month (date depending) … it will stop those pesky curious “is the baby here yet??” text messages coming through. These caring messages can be enough to spike your stress levels and delay labour a touch more… remember to focus on your awesome oxytocin and exceptional endorphin levels during this time! Applying patience can be super challenging, especially when you can feel that clock ticking in the maternity system. But again, as always, this is where hypnobirthing massively helps, not just for the mindset and breathwork techniques, but teaching you how to talk to medical professionals to get all the information you need to make informed decisions.

Being induced soon because of your EDD?

Then I highly recommend further reading here (an excellent website for evidence based information around birth!) https://evidencebasedbirth.com/evidence-on-due-dates/, and/or grabbing a copy of Dr Sara Wickham’s book “In Your Own Time”, also Dr Rachel Reed’s “Why Induction Matters”. 

Both on Audible if catching time to sit down with a book is tricky (like it is for me!)

The Saucy Summary:

As humans, we love putting things in boxes to organise and control them. We strive for perfection a lot of the time, especially in a medicalised world. 

“Systems need rules and pathways in order to avoid chaos. But as an individual seeking health care, you don’t have to follow any path that doesn’t feel right for you.”

The GLORIOUS Sara Wickam

The estimated due date is a tool for tracking pregnancy progression, but remember it is a heavily estimated guideline rather than an absolute deadline. As you prepare for your baby, embrace flexibility, patience, stay informed, and maintain open communication with your healthcare provider to contribute to a more positive and stress-free pregnancy.

After all, the ultimate goal is a healthy and happy birth where you feel informed and in control, whenever that magical moment may be.

Feeling the pressure? Any questions? You know where I am. Right here.

Nicki xx