The 16 Most Common Reasons For An Overdue Baby

Picture this: it’s the due date and the expecting parents are excited and a little apprehensive. Mom-to-be stays close to home in fear of her waters breaking in a public, dramatic display. She may go for a short walk or tackle some light cleaning around the house.

Phone calls and text messages pour in from friends and family asking the same question: “Feel anything yet?” While playing the waiting game, she puts her feet up, but by bedtime, there’s not even a hint of a contraction. Obviously, the little one didn’t get the memo.

When an expecting mom’s due date arrives and nothing happens, it’s a disappointing day for the mom-to-be. It’s agonizing because she’s been counting down to a particular day, and then nothing happens--like planning a big party, and then no one shows up. What’s going on? It means the game is going into extra innings.

It sure is difficult for the mom-to-be not to become discouraged when she’s flying in a pregnancy holding pattern. When “any day now” becomes her daily mantra, it’s only natural for her to struggle with patience. Yet, there are two pieces of good news with this situation. One, the end of pregnancy is near. And two, something will happen soon.

So, try to calm those nerves because there are several reasons why babies are overdue.

The flick of the switch that ignites labor is unknown, but lingering in pregnancy limbo can be explained in many ways. The most common reasons for an overdue baby are here.

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16 The Baby Is Not Ready For The World

The expecting parents may be ready for the baby, but the baby may not ready for the world. In the last few weeks of pregnancy, hormonal changes develop the heart, lungs, skin, and other organs the baby needs to survive in the outside world. This is why premature babies sometimes need help breathing because of their underdeveloped lungs.

The obstetrician or the midwife may want to induce labor at 41 weeks, or they may have a wait-and-see attitude. If the expecting mom is a couple of days past the due date, don’t expect the doctor to induce the labor right away. Medical professionals become more concerned when the baby is a couple of weeks overdue.

The obstetrician will assume the soon-to-be mom is more than ready to have her baby, as most women are in the later stages of pregnancy. Although mom-to-be is more than ready, the question remains, is the baby ready?

If there are no signs of labor the day after the due date, be patient. The mother-to-be will deliver any day now, and the baby will make his or her debut in good time.

15 Dates Are Incorrect Or Unknown

The date of ovulation is one of the most precise pieces of data needed to estimate the due date. If the mother-to-be has undergone In Vitro Fertilization, she will have the exact dates. Unfortunately, most women do not have this information. Also, ovulation to the following menstrual period is always 14 days.

For instance, if the woman has a 35-day cycle, she most likely ovulated on day 21. As long as she can pinpoint ovulation, she can determine a rough due date. If the ovulation date is unknown, a woman can use the date of conception to tell how long she has been pregnant.

Another way to find the estimated due date is by using the date of conception; add 266 days to this date. Also, conception happens 72 hours after ovulation. Some pregnancy wheels allow women to set the date of conception rather than the date of the last period.

Again, even if the date of conception is known, the date given will probably not be the baby’s actual birthday. A mere 5 percent of babies are born on the estimated due date. It’s more of a general idea of when to expect the newborn.

14 The Due Date Is An Educated Guess

Most women go into labor between their 37th and 42nd week of pregnancy. In fact, the medical term for being overdue is post-term which does not officially begin until two weeks after the due date. But, calculating the due date is not an exact science.

A mere 5 percent of babies are born on the estimated due date. The actual day the mother goes into labor will be up to her little one. The due date is an approximate calculation of when labor with start naturally. Although this is the date given to expecting parents, they should try not to become emotionally attached to this specific date because it’s not set in stone.

About 90 percent of pregnant women experience spontaneous labor within 14 days of their due date.

Plus, the expecting mother may have been told that she is 39 weeks pregnant when she is actually at week 38. A guesstimate is just that—an educated guess or an estimate of the arrival of the baby.

13 The LMP Date Is Uncertain

There are several methods that can help calculate when to expect a beautiful baby. The LMP calculation is pretty simple if the exact dates of the last menstrual period have been recorded. Day one is the first day of the last period. Add 9 months and 7 days, or 280 days.

This forecast assumes that conception was on the 14th day of your 28th-day cycle. But, not all women have 28-day cycles. For this reason, some ladies will need to adjust the dates of their last periods.

If the first day of the last period was a rough guess, the delivery date will be a little off. If the menstrual cycle dates are accurate, conception could still have happened at any time in the weeks to come.

If the date of the LMP is unknown, there's no reason to worry. In fact, it’s pretty common that women do not remember. However, knowing the date of conception will also work as a rough estimate.

12 The CRL Measurement Is An Estimate

The due date is best determined during the first ultrasound. This technology uses sound waves (inaudible to humans) to create an image of the baby. The ultrasound determines the baby’s growth and physical activity. It’s the size of the fetus that reveals how far along the mother-to-be is in the pregnancy.

During the ultrasound, the crown-rump length will be measured. This is the length of the baby from end to end, and this measurement is the best way to determine the age of the fetus. The earlier the ultrasound, the more accurate the prediction will be.

Although the approximate size of the fetus will be revealed during the ultrasound, the due date isn’t set in stone. About 90 percent of pregnant women experience spontaneous labor within 14 days of their due date. In any case, the actual day mom-to-be begins labor will be up to her little one.

11 It’s Not A Typical Pregnancy

Mom-to-be is probably saying “enough already” if her expected delivery date has passed. But, just because the due date has come and gone, it doesn’t mean that her labor is actually late. The estimated due date is about 40 weeks from the first day of her last period, but not all pregnancy lengths are the same.

Every soon-to-be mother and her unborn baby are biologically set for a particular length of pregnancy.

After 41 weeks, the obstetrician will keep a watchful eye on the pregnancy because post-term pregnancies are more likely to have some risks. For instance, the longer the placenta grows, the more it ages. If it gets old, it can prevent the baby from thriving. Also, the baby may develop too large, making labor and delivery longer and more difficult.

At 42 weeks, growth can slow or completely stop because the space in the womb has been maxed out.

At any rate, most women go into labor between their 37th and 42nd week of pregnancy. An overdue baby may be due to an atypical pregnancy.

10 The Baby’s Heartbeat Is An Estimation

Another way for a physician to figure out the length of a pregnancy is by listening to the baby’s heartbeat. An ultrasound fetal monitor can hear a fetal heart as early as 10-12 weeks into the pregnancy. A heartbeat evaluation can determine the fetal size, thereby determining the gestational age of the baby.

With regards to fetal heart rate, there are few biological differences between from one pregnancy to the next. However, some estimations fall outside of the range. While the fetal heartbeat is helpful in predicting the baby’s arrival, it’s not an absolute indicator of the due date.

Fetal maturity can be better determined with multiple indicators. Ultrasounds, a history of the woman’s menstrual cycles, and prenatal exam records, including fetal heart rates, all create a clearer picture as a whole. Still, prenatal testing can only estimate the gestational age because babies grow at different rates. With all methods of determining the delivery date, the margin of error is about two weeks.

9 The Fundal Height Is A Rough Estimate

There’s another method to estimate how far along a woman is in her pregnancy. It involves measuring the uterus in centimeters.

Take a measurement from the top of the uterus to the bottom of the pubic bone. This is known as the fundal height. After week 16 of pregnancy, this measure is the approximate number of weeks since the LMP. So, if the health care provider measures the fundal height is 28 centimeters, the mother-to-be is 28 weeks pregnant.

Although this is another method to find a rough estimate of the due date, it is not the most accurate way to find the age of the fetus. The fundal height can be off if the mother-to-be has a full bladder. The expecting mom can also measure larger is she is carrying multiple children, or if she is overweight. This is just another tool to gauge fetal growth, but it does not produce very accurate results.

8 Mom-To-Be Is Overweight

Overdue pregnancies are also linked to being overweight. Researchers in Australia found that an overweight body was less likely to respond when labor was triggered. Electrical signals found in the uterine muscle cells switch off for a pregnant woman who is within her body mass index, but they tend to persist for a woman with extra weight.

Shutting off these signals is what can ignite premature labor. This is why there is a higher rate of cesarean sections and induced labors with larger women.

Medical research is currently in the works to develop a medication that could help the uterine muscle to contract. The discovery of a new drug could assist women whose muscles do not contract on their own, including overweight, pregnant women. The challenge is inventing a medication that will not present any risks to the mother and the baby.

Unfortunately, a therapy like this for expecting moms will not be available for decades.

7 It’s A Boy

One of life’s greatest surprises is finding out the gender of a baby at birth. But if the pregnancy is overdue, the soon-to-be parents may be expecting a son.

Studies have found that boys not only produce longer pregnancies, but also longer labors. The apparent reason for the extra duration is that boys are typically heavier and larger than their female counterparts. Males also experience more complications than girls, such as cesarean sections, and assistance during delivery because of their larger heads.

Although gender may play a role in the length of pregnancy, there’s little difference between the sexes.

There are various causes of an overdue pregnancy because women experience pregnancy in different ways. The best way to determine the baby’s gender is to verify with a doctor, gynecologist, obstetrician, or health care professional. If the expecting mother is overdue, don’t buy a blue sleeper just yet.

6 Mom-To-Be Was Born Late

If the baby is taking an extended residence in the mom’s womb, there may be a biological reason. Was the mother-to-be born late? If so, it’s likely that her child will also be born late. Expecting moms tend to have prolonged pregnancies is they, themselves, were born later as pregnancy delays runs in the families.

In fact, if other women related to the mom-to-be has delivered past their due dates, the expecting mom is also likely to deliver late.

Having an overdue pregnancy has some risks. When the baby runs out of room in the uterus, growth can slow or completely stop, possibly resulting in a slowed heartbeat or another type of fetal distress. The need for a cesarean section rises, as does an assisted delivery using medical equipment such as forceps and a vacuum.

Because of the increased chance of the mother or the baby experiencing some type of complication, monitoring may be used. Non-stress tests, ultrasounds, and a record of fetal movements may be recommended by the health care provider.

5 She’s A First-Time Mother

Sometimes, the hardest part of pregnancy is the wait. Adverse side effects don’t help either. Backaches, swollen ankles, and sleep deprivation may be making the expecting mom’s life a little hellish. At this point, mom-to-be is probably tired of all of it.

It’s tempting for an overdue mom to try at-home techniques to speed up the childbirth process, but first-time moms are simply likely candidates for overdue deliveries.

For instance, a pregnant woman is prone to a delayed delivery if she is a first-time mother. One study found that women having babies for the first time gave birth five days later than experienced mothers. The explanation: first-time mothers are simply predisposed to longer pregnancies.

Expecting moms may be impatient for labor to begin, but they need to be cautious using home remedies to induce labor. Some strategies listed on the internet are fun, but some can be damaging. Check with an obstetrician or midwife before administering alternative treatments.

Firstborns are not guaranteed to be late, but chances are, they will make a fashionably late entrance. One thing that is for certain: after carrying a baby past 40 weeks, a pregnant woman will want to hug her mom.

4 A Previous Delivery Was Late

If the baby hasn’t appeared on schedule, it could be that the mother-to-be had a previous delivery that was also behind schedule. Having a full-term or postterm pregnancy once is anxiety-inducing enough. Going through an overdue pregnancy for the second time is yet again a stressful experience, but rest assured that the baby is probably doing fine.

If labor still hasn’t started naturally after 41 weeks, the mom-to-be may need to consult a doctor or midwife about a date for an early induction. But again, if there is a question about the delivery date, if may be preferable to delay an artificial induction. Being induced artificially has both pros and cons.

A cesarean section may be advised to prevent complications. The birthing team will evaluate if a surgical intervention is right. But no matter when labor begins, be happy that the arrival of your baby is just around the corner.

3 The Use Of Birth Control Pills Pre-Pregnancy

Some claim deliveries after the due date are due to taking birth control pills before the pregnancy. Using oral contraception just before becoming pregnant doesn’t guarantee that the mother-to-be will have an overdue baby, but the chances are higher.

When childbirth will begin is anyone’s guess, but a normal, healthy term usually ends before the 42nd week of pregnancy. Past this point, the mom-to-be will need to discuss her birthing options with her obstetrician or midwife during her next checkup. They can figure out if she may be a likely candidate for a C-section.

Waiting for labor can be stressful. A first-time mother waiting for childbirth to begin can worry even more. But what a soon-to-be mom needs to remember is that the due date is the estimated date she will naturally go into labor. That doesn’t mean it’s the best time for the baby to be born.

2 Mom-To-Be Had Irregular Periods

There are a number of reasons why a pregnant woman goes past her due date, including this important factor: if the mother-to-be has had a history of irregular menses, her baby may make a fashionably late entrance into the world.

There’s a reason why shifting menstrual cycles make due dates harder to pinpoint. Women with irregular periods often mistake early spotting during pregnancy for the start of their menstrual cycle. This would make the calculation of the LMP inaccurate.

Also, having irregular menses is more difficult to accurately predict the estimated due date. This is why medical professionals try to assess the due date using various data, not just the date of the last menstrual period.

Fear not because the baby will not take up permanent residence in the uterus, even if it feels that way right now. And, what most people call overdue is actually more common than not. It is normal to deliver a baby within two weeks of the estimated due date.

1 Nature Needs To Takes Its Course

40 weeks is long enough, not to mention if it continues into the 41st or 42nd week. Mom-to-be is probably tired of pregnancy and a little down in the dumps. She did not expect to be pregnant after her due date. But, only 10 percent of pregnant women experience prolonged pregnancies.

Since there is little a mom-to-be can do to expedite the process, it’s important for her to remember that overdue pregnancies occur for a reason.

Sometimes, it’s better to promote labor. For example, the size of the baby becomes a factor after 41 weeks. A big baby can put a vaginal delivery in jeopardy. To avoid complications, induction may be recommended by a health care provider. It is usually recommended between the 41st and the 42nd week of pregnancy.

If induction is necessary to lower the risk of complication, there are pros and cons to consider. Sometimes, however, it’s more appropriate to let nature take its course. Medical intervention is not always needed.

In the meantime, there are things mom-to-be can do besides twiddle her thumbs:

  • Nap as much as possible. Getting plenty of rest will build up energy reserves for labor.
  • Appreciate the quiet time and babysitter-free moments. Don’t be afraid to leave the house. See a movie, go out to dinner, go for a walk, or visit with friends and family.
  • Take pictures to savor the memories of the last days of pregnancy.
  • Precook meals, let me cool, and pack them in the freezer. After delivery, ready-to-eat home cooked meals that just need reheating will make life with a newborn easier.
  • If repeated phone calls and text messages are irritating, pre-record a voicemail message to let every caller know the labor status.
  • Keep in contact with medical professionals. Close examination will be necessary with every passing week. If there are any signs of labor, don’t be afraid to let them know.

Whether mom-to-be is scheduled to be induced, or she and her doctor decide to play the waiting game, she should try to enjoy whatever time remains of her pregnancy. Birth will happen when the time is right.

Sources: Women and Infants, AmericanPregnancy, Mayo Clinic, WebMD

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