Pregnancy is an exciting time, but it can also be overwhelming, especially when it comes to determin...

Have you noticed a discrepancy between LMP and ultrasound gestational age of your baby? Find out what are the possible reasons for this and what should you do.

Discrepancy Between LMP and Ultrasound Gestational Age: Causes & Implications

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Discrepancy Between LMP and Ultrasound Gestational Age: Expert Insights

When your doctor announces the date that your little one would pop out of your tummy, aren&#39;t you...

Changes in the due date is not uncommon and happens due to many reasons. Take a look to understand the various possible reasons behind this change.

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Know Why Your Doctor May Change Your Due Date During Pregnancy

Your pregnancy in weeks and months 
 
Pregnancy is a marvellous experience for a mother. However,...

What should every pregnant woman know about their pregnancy in terms of weeks and months?  

<p>When your doctor announces the date that your little one would pop out of your tummy, aren&#39;t you over the moon? You start imagining all sorts of things and plan accordingly. But what happens when your doctor changes the due date? Changes in the due date is not uncommon and happens due to many reasons. But before that, how is the due date calculated?</p>

<p>Your due date is calculated from the first day of your last period (or LMP) to the next 40 weeks. Your doctor chalks down a date at the end of the 40 weeks!</p>

<h2><strong>What Changes Your Due date?</strong></h2>

<p>The most common reasons why there could have been a mistake with the calculation of your due date are:</p>

<h3><strong>Irregular periods</strong></h3>

<p>If your periods are irregular, then how can your doctor depend on the first day of your last period? For women with irregular periods, an ultrasound is done to get an exact due date!</p>

<h3><strong>First ultrasound in the second trimester</strong></h3>

<p>If you got your first ultrasound during your second trimester instead of the first one, your due date is deemed to be inaccurate.</p>

<h3><strong>A Doppler date</strong></h3>

<p>Non-ultrasound confirmation of pregnancy is common. Maybe your doctor&#39;s timing was inaccurate because of this. (An early ultrasound, usually performed between 6 and 9 weeks, can provide the most precise due date estimation.)</p>

<h3><strong>Your Fundal height is above average</strong></h3>

<p>Each session will include a fundal measurement, which is the distance from the top of your pubic bone to the top of your uterus. Your uterine size may not match the normal growth charts (i.e., you measure big). If the measures are inaccurate by three weeks or more, your due date is often rescheduled.</p>

<h3><strong>You have elevated AFP</strong></h3>

<p>Between weeks 14 and 22, your doctor will likely order a blood test to check for AFP, or Alpha-fetoprotein, a protein ordinarily produced by your baby&#39;s liver and yolk sac. (Part of the quad screen.) While high levels of AFP can indicate a genetic defect, the most common cause is a missed due date.</p>

<h3><strong>Twin Pregnancy</strong></h3>

<p>Twin pregnancies can also be a cause of faulty due dates.</p>

<h3><strong>Birth Control Pills</strong></h3>

<p>If you got off the birth control pills right before you conceived, your due date could be incorrect.</p>

<p>Due dates change, and there is nothing to worry about it. All you have to do is take care of yourself and your baby all the time and be positive!</p>

<p>You may like: <a href="https://mylofamily.com/article/all-you-need-to-know-about-pregnancy-due-date-calculator-25700?utm_source=google%2Cadyogi&amp;utm_medium=search%2Cgoogle-search&amp;utm_campaign=12885700974%2CMYLO_7841_adyogi_Brand-Search_Engage_AllBrands&amp;AdSetID=118875105582&amp;AdID=ETA_DHL1&amp;gclid=Cj0KCQjwmdGYBhDRARIsABmSEeOaoGe0EOqhdAvLQKOwNc99ktoBxslxbHoI44yMfFjQe94OyU3daCYaAgKPEALw_wcB">All You Need To Know About Pregnancy Due date Calculator (mylofamily.com)</a></p>

<h3><strong>References</strong></h3>

<p>1. InformedHealth.org [Internet]. Cologne, Germany: Institute for Quality and Efficiency in Health Care (IQWiG); 2006. (2008). Pregnancy and birth: When your baby&rsquo;s due date has passed. NCBI</p>

<p> </p>


<p>Planning a pregnancy with irregular periods makes it difficult to predict the due date accurately, even with an online calculator. Instead, try these simple steps given below.</p>

<h2><strong>Introduction</strong></h2>

<p>When a woman has an irregular menstrual cycle, it is difficult to determine the date of conception and thus the due date. A woman can conceive at any time in her monthly cycle. The due date is calculated from the first day of the last menstrual period or LMP. This is because it is assumed that conception takes place about 14 days after the first day of the LMP.</p>

<p>The standard way to calculate a due date for an irregular menstrual cycle is to use a pregnancy calculator that considers &ldquo;cycle length.&rdquo;</p>

<p>There are many ways to determine when a woman&#39;s LMP was, including looking at past periods on calendars or keeping a journal of menstruation. The easiest way to find out when a woman&#39;s LMP was is by using an ovulation calculator. This simple program will help you try different dates until it finds the one that matches your cycles. Here are a few simple steps for you to calculate your pregnancy due date despite irregular periods.</p>

<h2><strong>How to calculate your due date?</strong></h2>

<p>Pregnancy, due date calculation, is an important part of pregnancy and childbirth. Calculating the due date can help you know the approximate time for delivery, which is important for prenatal care.</p>

<p>The due date is calculated by adding 280 days to the first day of your last menstrual period. This roughly estimates 40 weeks. If your menstrual periods are irregular, it may be difficult to calculate the due pregnancy date. You can use an online calculator to calculate your pregnancy due date. Due dates are calculated on the date of your last period instead of conception.</p>

<p>Still, if you cannot calculate your due date, an ultrasound can help you determine it. The best timing for an ultrasound is 8 weeks and 13 weeks. Let&#39;s see each step in a detailed manner to gain more clarity.</p>

<h3>1. Calculate using your LMP (last menstrual period)</h3>

<p>This is the most commonly used method and is accurate. It can be calculated by taking your period&#39;s start date into account and adding 280 days to it. This is the typical length of your pregnancy.</p>

<p>There is also a formula to calculate how far you are:</p>

<p>Days since start of LMP &divide; 7</p>

<h3>2. Calculate using a dating ultrasound</h3>

<p>A dating ultrasound is the most precise method to calculate your due date.</p>

<p>It measures the length of the fetus from crown to rump to estimate your due date or how far you are if it is completed within the first trimester. If you have irregular periods and face difficulty determining your last due date, you can simply go for a dating ultrasound to better analyze your due date.</p>

<h3>3. Calculate using a pregnancy test with weeks indicator</h3>

<p>Some pregnancy test indicators have a great feature of weeks indicator.</p>

<p>This can be super useful to you to determine how far you are. They detect your pregnancy by the presence of hormone hCG in urine and then state how many weeks pregnant you are.</p>

<p>By deducting the value from 40 weeks, you can estimate your due date roughly.</p>

<h2><strong>Determining Ovulation </strong></h2>

<p>The first step to determining your cycle dates is to figure out when you ovulate. It&rsquo;s not always easy to pinpoint ovulation. However, you should at least be able to identify the time of your cycle that is most likely to be ovulation. You can do this by keeping track of the days between your periods. Once you know the approximate number of days between your periods, subtract 14 from that number and keep track of the day on which it lands. For example, if your cycle lasts 36 days, ovulation will likely occur on day 22 or 23.</p>

<h2><strong>Determine Fertilization Date</strong></h2>

<p>One of the first steps to understanding your cycle is determining when you ovulate. Ovulation is a process that occurs during the middle of your cycle. This usually happens around Day 14. You need to track your menstrual cycles for a few months to determine this. When recording these periods, make sure they are recorded on the same day each month. Once you have a consistent recording, it will be easier to understand what pattern your body follows.</p>

<p>Another way to identify ovulation is by taking your basal temperature every morning for three days before and after ovulation. If you notice a dip in temperature, it means ovulation has occurred, and the fertile window has opened. If you have irregular periods, ovulation may not always occur on Day 14 but instead around Day 16. This can happen if your period cycles vary in length from one month to another. Use an ovulation calculator to determine when ovulation occurs for irregular periods.</p>

<h2><strong>Summary</strong></h2>

<p>This article explains how to determine your pregnancy due date with irregular periods. While it&rsquo;s not always a straightforward process, you can get a sense of when you may be expecting a little one with the proper knowledge and understanding.</p>

<p> </p>


Read this article to learn how you can calculate your pregnancy due date despite having irregular periods.

How to Calculate Your Pregnancy Due Date with Irregular Periods?

How to Determine Pregnancy Due Date with Irregular Periods?

<>Priyanka | Mylo Editor

<p style="text-align:justify"><span style="font-size:16px">Your pregnancy in weeks and months </span><br />
 </p>

<p style="text-align:justify"><span style="font-size:16px">Pregnancy is a marvellous experience for a mother. However, it can be extremely challenging, especially if you are experiencing it for the first time. During the first pregnancy, you don&rsquo;t know what to expect and what not to expect. Although you might have experienced it first-hand with your close relative or friend, nothing can prepare you for this experience.  </span></p>

<p style="text-align:justify"><span style="font-size:16px">It is important to educate yourself with every piece of information as it will enable you to understand what your body is going through. It is important to understand every stage of your pregnancy as it will act as a milestone for your journey and help you navigate through it easily.  </span></p>

<p style="text-align:justify"><span style="font-size:16px">The most important thing to know about pregnancy is its duration and what every month means for you and your baby. In a normal pregnancy, there are 40 weeks, although you can deliver your baby prematurely or after your due date according to your situation and the baby&#39;s development.  </span></p>

<p style="text-align:justify"><span style="font-size:16px"> <br />
<strong>There are three trimesters: </strong></span></p>

<ul>
	<li>
	<p style="text-align:justify"><span style="font-size:16px">The first trimester (early pregnancy) </span></p>
	</li>
	<li>
	<p style="text-align:justify"><span style="font-size:16px">The second trimester (mid-pregnancy) </span></p>
	</li>
	<li>
	<p style="text-align:justify"><span style="font-size:16px">The third trimester (late pregnancy) </span></p>
	</li>
</ul>

<p style="text-align:justify"><strong><span style="font-size:16px">Each trimester is 13 or 14 weeks long.  </span></strong></p>

<p style="text-align:justify"><span style="font-size:16px">The first trimester lasts until you are 13 weeks pregnant, the second trimester spans week 14 to week 27, and the third trimester starts the day you turn 28 weeks pregnant and lasts until you deliver your baby. Each trimester is three months long and has its own set of changes that the body and the baby undergo. </span></p>

<p style="text-align:justify"><span style="font-size:16px">Your 40 weeks of pregnancy are counted as nine months. But there are four weeks in a month, which would make 40 weeks ten months, but it is not that simple. Four weeks is 28 days, but one months have 30 or 31 days, making each month about 4.3 weeks long. So, this is a chart to calculate the weeks, months, and trimesters of pregnancy. </span></p>

<p style="text-align:justify"><strong><span style="font-size:16px">Trimester 1 </span></strong></p>

<p style="text-align:justify"><span style="font-size:16px">Month 1: Weeks 1 to 4 </span></p>

<p style="text-align:justify"><span style="font-size:16px">Month 2: Weeks 5 to 8 </span></p>

<p style="text-align:justify"><span style="font-size:16px">Month 3: Weeks 9 to 13 </span></p>

<p style="text-align:justify"><strong><span style="font-size:16px">Trimester 2 </span></strong></p>

<p style="text-align:justify"><span style="font-size:16px">Month 4: Weeks 14 to 17 </span></p>

<p style="text-align:justify"><span style="font-size:16px">Month 5: Weeks 18 to 22 </span></p>

<p style="text-align:justify"><span style="font-size:16px">Month 6: Weeks 23 to 27 </span></p>

<p style="text-align:justify"><strong><span style="font-size:16px">Trimester 3 </span></strong></p>

<p style="text-align:justify"><span style="font-size:16px">Month 7: Weeks 28 to 31 </span></p>

<p style="text-align:justify"><span style="font-size:16px">Month 8: Weeks 32 to 35 </span></p>

<p style="text-align:justify"><span style="font-size:16px">Month 9: Weeks 36 to 40 </span></p>

<p style="text-align:justify"><span style="font-size:16px">Typically, the best way to estimate your due date is to count 40 weeks, or 280 days, from the first day of your last menstrual period (LMP). </span></p>

<p style="text-align:justify"><span style="font-size:16px">This information will help you understand your due date and what to expect in every trimester. Your doctor also gives you an estimated due date by calculating using this chart, so by knowing it yourself, you can understand the whole process more efficiently.  </span></p>

<p style="text-align:justify"><span style="font-size:16px">You may also like: </span></p>

<p> </p>

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<p>Pregnancy is an exciting time, but it can also be overwhelming, especially when it comes to determining the <a href="https://mylofamily.com/article/all-you-need-to-know-about-pregnancy-due-date-calculator-25700">due date of the baby</a>. Gestational age is a term used to describe the age of the baby in weeks and days from the first day of the last menstrual period (LMP). The due date is calculated by adding 40 weeks or 280 days to the first day of the LMP. However, the due date can also be determined by ultrasound, which measures the size of the baby and calculates the due date based on that measurement. </p>

<p>In this article, we will understand the possible causes and implications of discrepancy between LMP and ultrasound gestational age and what is more accurate ultrasound due date or LMP.  </p>

<h2><strong>Understanding LMP and ultrasound gestational age </strong></h2>

<p>The LMP is used to determine the gestational age of the baby because it is the most accurate way to determine when the pregnancy began. The LMP is the first day of the last menstrual period, and it is used to calculate the due date by adding 40 weeks or 280 days. Ultrasound gestational age, on the other hand, is determined by measuring the size of the baby. The ultrasound technician measures the baby from head to bottom, and the <a href="https://mylofamily.com/article/crown-rump-length-crl-on-ultrasounds-194540?">CRL measurement</a> is used to calculate the due date. </p>

<h2><strong>Causes of discrepancy between LMP and ultrasound gestational age </strong></h2>

<p>There are several reasons why there may be a difference between LMP and ultrasound gestational age.</p>

<h3>1. Irregular periods</h3>

<p>One of the most common reasons is that the LMP may not be accurate. Women may have irregular menstrual cycles, making it difficult to determine the first day of the last menstrual period.</p>

<p>You may also like: <a href="https://mylofamily.com/article/how-to-determine-pregnancy-due-date-with-irregular-periods-156098">How to Determine Pregnancy Due Date with Irregular Periods?</a></p>

<h3>2. Implantation bleeding</h3>

<p>Some women may experience implantation bleeding when the conceive. <a href="https://mylofamily.com/article/is-it-implantation-bleeding-%E2%80%94-or-just-my-period-1546?">Implantation bleeding</a> is light spotting that may occur when a fertilized egg implants itself in the lining of the uterus. This usually happens 6-12 days after fertilization and can be mistaken for a light period, leading to an inaccurate LMP. </p>

<h3>3. Fetal growth rate</h3>

<p>Another reason for the discrepancy could be that the <a href="https://mylofamily.com/article/fetal-growth-restriction-fgr-in-pregnancy%20overview-215599">baby is growing at a different rate</a> than expected. This can happen if the baby is smaller or larger than average. It can also happen if the baby is growing at a slower or faster rate than expected.</p>

<h3>4. Ultrasound timing</h3>

<p>Lastly, the timing of the ultrasound can affect the gestational age. If the ultrasound is done early in the pregnancy, the gestational age may be underestimated. If the ultrasound is done later in the pregnancy, the gestational age may be overestimated. </p>

<p>You may also like: <a href="https://mylofamily.com/article/sonography-after-four-weeks-167411">Why Is It Crucial To Get Sonography Done After Four Weeks Of Pregnancy?</a></p>

<h2><strong>Implications of discrepancy between LMP and ultrasound gestational age</strong></h2>

<p>The discrepancy between LMP and ultrasound gestational age can have several implications. If the ultrasound due date is earlier than the LMP due date, it could mean that the baby is not as far along as originally thought. This could affect the timing of important tests and procedures, such as the <a href="https://mylofamily.com/article/an-expecting-mothers-guide-to-glucose-tolerance-test-gtt-25414?">glucose tolerance test</a> and the Group B strep test. Additionally, if the ultrasound due date is later than the LMP due date, it could mean that the baby is at risk of being born prematurely. </p>

<h2><strong>What is more accurate ultrasound due date or LMP?</strong></h2>

<p>It is difficult to say which due date is more accurate because it depends on the individual situation. If the LMP is known and the menstrual cycle is regular, the LMP due date is likely to be accurate. However, if the menstrual cycle is irregular, the LMP due date may not be accurate. Additionally, if the ultrasound is done early in the pregnancy, the ultrasound due date may not be accurate. </p>

<p>You may also like: <a href="https://mylofamily.com/article/know-why-your-doctor-may-change-your-due-date-duri-25696">Know Why Your Doctor May Change Your Due Date During Pregnancy</a></p>

<h2><strong>Should I go by LMP or ultrasound due date?</strong></h2>

<p>It is recommended that women go by the ultrasound due date if there is a discrepancy between the LMP and ultrasound gestational age. This is because the ultrasound due date is based on the <a href="https://mylofamily.com/article/fetal-growth-and-development-during-pregnancy-200178?">size of the baby</a>, which is a more accurate way to determine the due date. However, if the LMP due date is more accurate, the healthcare provider may recommend going by that due date instead. </p>

<h2><strong>What if there is a 1 week difference between LMP and ultrasound gestational age?</strong></h2>

<p>If there is a 1 week difference between LMP and ultrasound gestational age, it is usually nothing to be concerned about. This small discrepancy is within the range of normal and is unlikely to affect the timing of <a href="https://mylofamily.com/article/what-are-the-common-tests-you-will-have-during-your-pregnancy-128722">important tests and procedures</a>. </p>

<h2><strong>What if there is a 2 weeks difference between LMP and ultrasound gestational age?</strong></h2>

<p>If there is a 2 weeks difference between LMP and ultrasound gestational age, it is important to discuss this with the healthcare provider. This larger discrepancy could indicate that the baby is not growing at the expected rate or that there is a problem with the pregnancy. The healthcare provider may recommend <a href="https://mylofamily.com/article/a-pregnant-womans-guide-to-prenatal-visits-25385">additional ultrasounds or tests</a> to monitor the pregnancy and ensure the health of the baby. </p>

<h3>The Bottomline </h3>

<p>The due date of a baby is an important milestone in pregnancy, but it can also be confusing and overwhelming. It is not uncommon for there to be a discrepancy between LMP and ultrasound gestational age, and there are several potential causes for this difference. If there is a discrepancy, it is important to discuss this with the healthcare provider and follow their recommendations for monitoring the pregnancy. By working together, women and their doctors can ensure the health of the baby and a safe delivery. </p>

<h3>References</h3>

<p>1. Kullinger M, Granfors M, Kieler H, Skalkidou A. ( 2018). Discrepancy between pregnancy dating methods affects obstetric and neonatal outcomes. Sci Rep.</p>

<p>2. Morgan JA, Cooper DB. (2022). Pregnancy Dating. NCBI</p>


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