Fundal Height Chart for Twins

Estimated centiles and standard deviation per gestational week

Table Fundal Height Twins

* Estimated centiles (c) and S.D. per gestational week (GW). Measurement in centimeters.

Although mean fundal height is substantially greater in twin than singleton pregnancies, the value of the technique to detect growth disturbances in multiple pregnancies may be limited.

Reference

  1. Staub D, Harpes P, Zimmermann R, Ochsenbein-Kölble N. Reference curves of symphysis-fundus height in twin pregnancies. Eur J Obstet Gynecol Reprod Biol. 2006 Sep-Oct;128(1-2):236-42.

Fundal Height: What does it mean?

A fundal height measurement is generally defined as the distance in centimeters from the pubic bone to the top of the uterus. The expectation is that after week 24 of pregnancy, the fundal height for a normally growing baby will match the number of weeks of pregnancy — plus or minus 2 centimeters. For example, if you’re 27 weeks pregnant , your health care provider would expect your fundal height to be about 27 centimeters.

What does a fundal height measurement tell us?

Fundal height measurements can be used to determine if a baby is small for its gestational age . If the measurement is significantly smaller than what is expected, it may indicate that the baby is not growing properly and may need further evaluation.

For example, if you’re 27 weeks pregnant, your health care provider would expect your fundal height to be about 27 centimeters. If it’s significantly less than that, it could indicate a problem with the baby’s growth.

How the fundal height is measured?

To take a fundal height measurement, your health care provider will simply measure the distance from your pubic bone to the top of your uterus. A tape measure is used to check the distance between these areas and record the measurement in centimeters (cm).

The zero marker is placed at your pubic bone, and the tape measure is pulled up to the top of your uterus. This is your fundal height measurement.  This measurement can be done at each prenatal visit starting around week 24 of pregnancy.

How Fundal Height is Measured
Illustration showing how fundal height is measured.

When a tape measure is unavailable, finger widths are used to estimate centimeter (week) distances from a corresponding anatomical landmark.

What can affect the fundal height measurement?

There are a few things that can affect the fundal height measurement:

  • The position of your baby during the measurement (babies tend to move around a lot!)
  • The amount of amniotic fluid surrounding your baby
  • Your abdominal muscle tone (if you have very toned abs, it may be harder to get an accurate measurement)
  • Whether you are carrying twins or multiples

What is a normal fundal height?

As your pregnancy progresses, your fundal height measurement will change. The fundus is the uppermost part of the uterus, and during pregnancy, it grows as the baby develops.

At 12 weeks, the fundus is at the level of the pubic bone. By 16 weeks, it’s usually halfway between the pubic bone and the belly button (the umbilicus). By 20 weeks, it typically reaches the belly button. After 24 weeks, the measurement in centimeters should match (within a centimeter or two in each direction) the gestational age of your baby. So if you’re 25 weeks pregnant, your fundal height should be about 23 to 27 centimeters. After 36 weeks, the fundal height may decrease as the baby engages in your pelvis (moves down) in preparation for labor.

In the later stages of pregnancy, the fundal height may decrease as the baby engages in your pelvis (moves down) in preparation for labor. About an hour after delivery, your uterus will go down to where it was at 20 weeks (around your belly button).

Fundal Height Chart
International fundal height standards for clinical use.

What can cause a small fundal height measurement?

There are many possible causes of a small fundal height measurement, including:

  • Pregnancy complications such as preeclampsia or gestational diabetes
  • Poor nutrition
  • Infection
  • Abnormalities of the uterus or cervix
  • Certain medications such as steroids
  • Smoking

If you have a small fundal height measurement, your health care provider will likely order further testing to determine the cause. This may include an ultrasound or other imaging tests, as well as blood tests.

Treatment for a small fundal height will depend on the underlying cause. If the cause is a pregnancy complication, treatment may involve close monitoring of the pregnancy and/or delivery by cesarean section. If the cause is poor nutrition, your health care provider may recommend changes to your diet.

What can cause a large fundal height measurement?

There are several possible causes of a large fundal height measurement, including:

  • Multiple gestation ( twins or triplets)
  • Hydramnios (too much amniotic fluid)
  • Macrosomia (a large baby)
  • Obesity

If you have a large fundal height measurement, your health care provider will likely order further testing to determine the cause.

Detecting abnormal fetal growth

As any expectant parent knows, the health of their unborn child is of the utmost importance. One way to gauge the well-being of a fetus is to track its growth. Fetal size, as defined by estimated fetal weight, is a good indicator of overall health. A fetus is considered small if it falls below the 10th percentile for its gestational age, and large if it is above the 90th percentile. If a fetus falls within these limits, its size is considered appropriate for its gestational age. Tracking fetal growth can therefore give doctors and parents valuable information about the health of the fetus. In addition to monitoring for appropriate growth, doctors also look for signs of abnormalities such as macrosomia (abnormally large size) or microcephaly (abnormally small head). By keeping an eye on fetal growth, doctors can ensure that fetuses are developing normally and flag any potential problems.

Why is important to know my gestacional age?

Determining the gestational age of a fetus is an important part of prenatal care. Accurate dating is essential for assessing the risk of preterm labor and delivery, as well as for determining the appropriate timing and course of other interventions, such as antenatal testing and induction of labor. There are two primary methods for estimating gestational age: using the first day of the last menstrual period (LMP) or using ultrasound. Your doctor will likely use both methods to get the most accurate estimate. The LMP method is based on the principle that ovulation occurs approximately 14 days after the start of the last menstrual period. This method is only reliable, however, if you have a regular menstrual cycle. If your cycles are irregular, your doctor may instead rely on ultrasound to estimate gestational age. Ultrasound dating is based on measurements of fetal structures, such as the length of the femur (thigh bone), and can be performed as early as 10-12 weeks into pregnancy. Gestational age estimation is an inexact science, but it is an important tool for ensuring a healthy pregnancy.

What are the risks of fundal height measurements?

There are no risks associated with having a fundal height measurement. Your healthcare provider will measure your fundal height at each prenatal consultation after 24 weeks.

The Best Sunscreens for Pregnancy: What to Look For on the Ingredients Label

When you’re pregnant, it’s especially important to protect your skin from the sun. The American Academy of Dermatology recommends using a sunscreen with an SPF of 30 or higher every day. But not all sunscreens are safe for pregnant women. Some ingredients in sunscreen can be harmful to your baby. So, what should you look for on the ingredients label?

Why is using sunscreen important when you’re pregnant?

Not only will sunscreen protect you from skin cancer, but it will also shield your skin from discoloration and other pregnancy-related conditions that can be exacerbated by sun exposure.

Since your skin tends to be more sensitive when you’re pregnant, melasma and other kinds of hyperpigmentation — blotches, patches, dots or lines that can vary in color from reddish-purple to brown, blue or gray — are more of a possibility and can become more pronounced when you’re exposed to the sun.

So what should you look for on the ingredients label?

The first thing to look for is the SPF, or sun protection factor. This tells you how well the sunscreen will protect your skin from the sun’s harmful rays. The higher the SPF, the better. But experts say that no sunscreen can block all of the sun’s rays, so it’s still important to wear protective clothing and stay in the shade when possible.

Another ingredient to look for is zinc oxide. This is a mineral that helps block both UVA and UVB rays. It’s considered safe for pregnant women and babies, and it’s often used in baby sunscreen because it’s less likely to irritate their skin.

Some sunscreens also contain titanium dioxide. This is another mineral that helps block both UVA and UVB rays. But unlike zinc oxide, it’s not considered safe for pregnant women or babies. So, if you’re looking for a sunscreen for pregnancy, make sure it doesn’t contain titanium dioxide.

Finally, avoid sunscreens that contain retinyl palmitate. This is a form of vitamin A that can be harmful to your baby if you use it while you’re pregnant.

What are some of the best sunscreens for pregnancy?

Now that you know what to look for on the ingredients label, here are some of the best sunscreens for pregnancy:

  • The Honest Company SPF 50 Mineral Sunscreen
  • Neutrogena Pure & Free Baby Mineral Sunscreen SPF 50
  • Aveeno Baby Continuous Protection Zinc Oxide Mineral Sunscreen SPF 50
  • CeraVe baby lotion SPF 45
  • Banana Boat Simply Protect Baby sunscreen lotion SPF 50+

What sunscreen is not safe during pregnancy?

When it comes to choosing a sunscreen for pregnancy, the most important thing is to read the ingredients label. Look for sunscreens that contain zinc oxide and avoid those that contain retinyl palmitate. And remember, no matter what sunscreen you choose, it’s still important to wear protective clothing and stay in the shade when possible.

Is sun exposure important during pregnancy?

So, while you should definitely take precautions against too much sun exposure, some sun exposure is still important for your health during pregnancy. Most research points to as little as five to ten minutes of sun exposure two to three times a week on the arms, legs, hands and/or face to meet all of the body’s vitamin D needs.

So, while you should definitely take precautions against too much sun exposure, some sun exposure is still important for your health during pregnancy. Just be sure to choose a safe sunscreen and don’t stay in the sun for too long.

If you have any questions about which sunscreen is right for you, be sure to ask your doctor or dermatologist. They can help you choose a sunscreen that will be safe for both you and your baby.

When do you start leaking colostrum?

Colostrum is the first milk you have in your breasts. It is a thick, yellowish fluid that contains antibodies and other nutrients that help to protect your baby during his or her first few weeks of life. Women start to produce colostrum from about sixteen weeks of pregnancy onwards. Some women find that they leak colostrum from their breasts as early as 28 weeks of pregnancy.

If this happens to you, don’t worry – it’s perfectly normal! Just make sure to wear a breast pad to avoid any embarrassing accidents! And do not worry if you do not – it is not an indicator of whether you will have milk for your baby. Sometimes, women’s bodies simply do not produce colostrum. This is perfectly normal too!

Why colostrum is important?

Colostrum is important because it contains antibodies and other nutrients that help to protect your baby during his or her first few weeks of life. The antibodies contained in colostrum serve as vaccines, allowing the mother to pass on immunity to her baby from many germs that could otherwise harm him or her. There is a much higher concentration of these antibodies in colostrum than there is in mature breast milk.

It also contains the nutrients that newborns need for healthy brain, heart, and central nervous system development. Colostrum is high in carbohydrates and protein but low in fat, and will help the baby pass his or her first stools, which is important to prevent jaundice.

Colostrum

Does leaking colostrum early mean good milk supply?

Leaking colostrum or the ability to hand express colostrum IS NOT a good indicator of supply postpartum, so don’t worry if you’re not seeing any or don’t want to collect. If you’ve had low supply in the past, this is a great way to stock up on milk before baby is born.

Does leaking colostrum mean Labor is close?

No, leaking colostrum does not necessarily mean that labor is close. It can happen days, weeks, or even hours before labor begins. If your water breaks or you experience contractions, those are more reliable signs that labor is imminent.

How do you know if your colostrum is leaking?

You may notice that your breasts feel fuller or heavier than usual, or that you have a small amount of yellowish fluid on your nipples. If you’re not sure whether what you’re seeing is colostrum, you can try expressing a little bit onto a clean finger and tasting it – it should be thick and slightly sweet.

If you think you’re leaking colostrum, it’s a good idea to wear breast pads to protect your clothing. You can also try using a pump to collect the colostrum and store it in the freezer for use after baby is born.

Can I squeeze milk out while pregnant?

Yes, you can squeeze milk out while pregnant. However, it is not advisable to do this too often as it can lead to infection. If you must express milk, make sure to wash your hands and breasts thoroughly beforehand. You should also sterilize any equipment that you use.

The big worry here is that squeezing out milk or colostrum could induce contractions. This is because nipple stimulation causes an increase in the hormone oxytocin, which is involved in both milk release and womb contraction.

Early Signs and Symptoms of Pregnancy

While a missed period is one of the most classic early pregnancy symptoms, there are actually a ton of other signs that a positive pregnancy test may be in your future. We asked our readers what some of their signs and symptoms of early pregnancy were, and some of the answers may surprise you.

Here are some signs and symptoms of early pregnancy that our readers reported:

Nausea and vomiting

While “morning sickness” is most commonly associated with early pregnancy, nausea and vomiting can actually happen at any time of day. If you’re feeling nauseous, try drinking a ginger tea or nibbling on some ginger snaps.

Fatigue

Feeling exhausted all the time is another one of those early pregnancy symptoms that can be confusing. After all, don’t we all feel tired sometimes? But if you’re noticing that you’re extra fatigued and you can’t seem to get rid of it no matter how much rest you get, it could be an early sign of pregnancy.

Bloating

Many women report feeling bloated early on in their pregnancy. This is likely due to the hormone progesterone, which relaxes smooth muscle tissue throughout your body, including in your digestive tract. This can lead to constipation and gas, both of which can contribute to bloating.

Food cravings or aversions

Hormones can also cause food cravings or aversions. If you find yourself suddenly wanting (or not wanting) certain foods, it could be an early sign of pregnancy.

Breast changes

Another early symptom of pregnancy is changes in your breasts. Many women report feeling their breasts become more tender or sensitive. You may also notice that your nipples are darker or that your breasts are larger. These changes are due to the increased levels of hormones in your body.

Mood swings

If you find yourself feeling inexplicably sad or angry, it could be an early sign of pregnancy. Hormones can wreak havoc on your emotions, and you may find yourself crying for no reason or feeling more irritable than usual.

Frequent urination

If you find yourself needing to go to the bathroom more often than usual, it could be an early sign of pregnancy. This is due to the hormone hCG (human chorionic gonadotropin), which is produced in large quantities during early pregnancy.

Headaches

Many women report headaches as an early pregnancy symptom. These can be due to the increased levels of hormones in your body or from the extra stress of being pregnant. If you’re struggling with headaches, try drinking plenty of fluids and getting some rest.

Constipation or diarrhea

Changes in your digestive system are another common early symptom of pregnancy. Hormones can slow down your digestion, which can lead to constipation. Alternatively, you may find yourself dealing with diarrhea. If you’re struggling with either of these, try to eat nutritious foods and drink plenty of fluids.

If you’re experiencing any of these signs and symptoms, it’s possible that you could be pregnant. The best way to confirm a pregnancy is with a test from your doctor or a home pregnancy test.

These are just a few of the signs and symptoms of early pregnancy. If you think you may be pregnant, the best thing to do is take a home pregnancy test or make an appointment with your doctor.

Pregnancy can be a very exciting time, but it can also be confusing and overwhelming. If you’re feeling lost or need some help navigating this new stage in your life, we’re here for you.

Have you already seen our pregnancy due date calculator? If you are pregnant and need to find out your due date, you can use it!.

Cryptic Pregnancy

Cryptic pregnancy, also known as stealth pregnancy, is a pregnancy in which a woman is unaware that she is expecting a baby until halfway through it, or even up until labor or birth. It can be a startling and overwhelming experience for both the mother and those around her. Television shows like MTV’s “I Didn’t Know I Was Pregnant” showcase extreme examples of this condition, when woman finds out her pregnancy only when signs of labor are present.

There are many reasons why a woman might not know she is pregnant. Perhaps she has irregular periods and so doesn’t realise she’s missed one. Maybe she’s on the Pill or another form of contraception and so doesn’t expect to get pregnant. Or she could be dealing with other issues in her life that make her distracted or stressed, meaning she doesn’t notice the early signs of pregnancy.

It’s estimated that cryptic pregnancies happen in around 1% of all pregnancies, though the true figure may be higher as many women who have them don’t come forward. If you think you might be pregnant but have no idea how far along you are, it’s important to see a doctor as soon as possible so they can confirm the pregnancy and help you plan for the weeks and months ahead.

How do I you know if I have a cryptic pregnancy

While cryptic pregnancy is rare, it’s important to be aware of the signs and symptoms so you can be sure to get the medical care you need if it does happen to you. The most common symptom is actually feeling pregnant even though you’re not showing any physical signs like a growing belly. You might also experience nausea, fatigue, food cravings or aversions, mood swings, and breast changes.

Even if you do not have a baby bump you might consider de possibility of denied or concealed pregnancy. If you have any of the mentioned signs or symptoms, contact your health care provider as soon as possible.

Can I take a pregnancy test?

Yes! If you think you might be pregnant you should take a pregnancy test right away. Cryptic pregnancy can be difficult to diagnose because the early symptoms are similar to those of other conditions, so a test is the best way to know for sure.

Can I get pregnant if I am on birth control?

Even if someone is on birth control, there’s still a possibility that they can get pregnant if they’re having unprotected sex. Cryptic pregnancy can happen to anyone. Birth control isn’t always foolproof. Even when used correctly, it’s possible to become pregnant. Those who use birth control may assume they’re safe and ignore pregnancy symptoms.

What causes cryptic pregnancy

There is no one cause of cryptic pregnancy. In some cases, it may be due to irregular periods or other hormonal issues that make it difficult to notice the early signs of pregnancy. In other cases, it may be because the woman is under a lot of stress or dealing with other issues in her life that make her distracted or less likely to notice physical changes. Cryptic pregnancies can also occur in women who have had previous miscarriages or abortions, as they may be less likely to believe they are pregnant again when they miss a period.

Typical Pregnancy Symptoms

There are a variety of physical and emotional symptoms that women experience during pregnancy. These symptoms can vary in intensity and may be different for each woman. The most common early symptoms of pregnancy include:

  • Missed period
  • Nausea or vomiting
  • Morning sickness
  • Breast changes
  • Fatigue
  • Food cravings or aversions
  • Mood swings
  • Weight gain or loss
  • Headaches
  • Heartburn
  • Constipation or diarrhea

If you’re experiencing any of these symptoms, it’s important to take a pregnancy test as soon as possible to confirm whether or not you are pregnant. Cryptic pregnancy can be difficult to diagnose, so a test is the best way to know for sure. If you find out you´re pregnant check out our due date calculator.

Can I have a period while on denied pregnancy?

Yes, you can. Actually most probably your having a first trimester bleeding and not a period. Also there is the implantation bleeding  caused by the egg implanting itself in the uterus. It can occur around the time of a woman’s expected period and may be mistaken for a regular period.

What are the risks of cryptic pregnancy?

There are a number of risks associated with cryptic pregnancy, both for the mother and the baby.

Cryptic pregnancy can be dangerous for the mother if she is not getting the proper medical care. This can lead to complications like preeclampsia, gestational diabetes, and infection.

Cryptic pregnancy can also be dangerous for the baby. If the mother is not getting proper prenatal care, the baby may not be getting the nutrients and screenings they need. This can lead to a variety of health problems, including low birth weight, premature delivery, and congenital abnormalities.

What is a normal fetal heart rate?

When you heard your baby’s heartbeat through ultrasound monitoring, you were probably delighted, entranced and mystified by that tiny, internal life. You might have also wondered if your baby’s fetal heart rate was normal during your pregnancy. We promise, this isn’t the first time you’ll wonder if your baby’s development is “normal” in comparison to others. While most pregnant women won’t get to hear their baby s heartbeat in the first week, or even the first trimester, this shouldn’t make you worried – you can hear it as early as the sixth week! The fetal heart rate varies during the stages of pregnancy, and with help from regular health care, monitoring and frequent ultrasound appointments, it won’t be long before the time comes to hear that first beat. Click on the bar below to hear a fetus’ heartbeat!

At about 5 weeks of gestation during pregnancy, your baby’s heart begins to beat, and you will get to hear your baby s fetal heart rate with an external method such as a Doppler ultrasound. Doppler device uses sound waves using fluid in the amniotic sac to check the flow of blood in the baby, and is also used when monitoring the baby’s heart rate.

During this trimester, the baby s heartbeat is slightly higher than that of the mother, about 100 beats per minute (bpm). From this point on during pregnancy, the baby s heart rate frequency will increase by around 3 beats per minute per day during that first month. This system is so accurate that your doctor could use the mother s heart rate to help determine your baby’s gestational age.

Fetal Heart Rate on Ultrasound
Normal fetal heart rate on ultrasound

By the beginning of the 9th week of pregnancy, the normal fetal heart rate is an average of 175 bpm (beats per minute). At this point, a rapid deceleration of the fetal heart rate begins, reaching around 110-160 beats per minute in mid-gestation. There is also a slow deceleration in fetal heart rate in the last ten weeks of pregnancy. It is important to note that variations in a baby s heart rate is normal, just as with an adult’s heart rate. Whether it will get higher or lower, rest assured your baby is fine! You will find that sleep, movement, and other related prenatal activities can contribute to these normal, healthy variations in your baby s heart rate, and your doctor has a system to test and monitor each beat. 

Fetal Heart Rate Reference Table

Gestational Age / Fetus Size Normal Fetal Heart Rate
2 mm embryo 75 beats per minute (bpm)
5 mm embryo 100 beats per minute (bpm)
10 mm embryo 110 bpm to 120 bpm
15 mm embryo 130 beats per minute (bpm)
5 Weeks starts at 80 and ends at 103 bpm
6 Weeks starts at 103 and ends at 126 bpm
7 Weeks starts at 126 and ends at 149 bpm
8 Weeks starts at 149 and ends at 170 bpm
9 Weeks 155-195 bpm (average 175 bpm)
12 Weeks 120-180 bpm (average 150 bpm)
After 12 Weeks 110-160 bpm (average 140 bpm)
Normal Fetal Heart Rate During Pregnancy

What is a False-Positive Reading?

False-positive fetal heart rate monitoring readings – which may indicate there is a problem when the baby is actually fine – are common.Your doctor has a range to classify your baby’s prenatal development and fetal heart rate readings during pregnancy. The range is reviewed according to three categories:

  • Category One: Everything is normal and no action or test is needed.
  • Category Two: Readings are unclear and may be further reviewed, or require more internal information such as an additional test, evaluation and surveillance.
  • Category Three: Readings around the heart rate are abnormal (higher or lower) and may require prompt evaluation and action.

Medical professionals can see fairly early on when a baby s heart looks normal and healthy (category 1) and know when something is wrong during gestation and we need to take immediate action (category 3). In the middle, it may get complicated, and this range is where false-positives often show up based on what your doctor can and can’t see through external ultrasound monitoring. A lot of factors go into assessing if a baby is healthy during birth – for example, the mother’s pregnancy health from the first trimester affects the baby, and must be reviewed as early as possible. This is where the use of one device can’t replace the care of a good doctor. The results are usually related to the context of what’s going on around gestation during any given week, and we know an internal fetal heart rate device can’t give us this information.

What can fetal heart rate monitoring tell us about your baby’s heartbeat during labor?

If you’re between 38-42 weeks in your pregnancy and you’ve gone into labor, your medical team will immediately set up fetal heart rate monitoring to first asses your baby’s heartbeat and health during birth. The main purpose of fetal heart rate monitoring is to provide information by observing your baby s heartbeat and alerting your doctor if your baby may not be getting enough oxygen or blood flow. We want to see your healthy baby come through pregnancy, labor and delivery as smoothly as possible. We don’t want the stress of labor to threaten a baby s heart, health or development, which is why a monitoring system as early as possible is so essential.

A baby s heart rate during labor should be between 110 and 170 bpm (beats per minute) depending on which week you’ve gone into labor, but it may fluctuate above or below this rate for a variety of reasons. Short bursts of acceleration of the baby’s heart rate are usually common and indicate that the baby is getting an adequate oxygen supply. We know that brief decelerations in the baby s heart rate are also normal and do not indicate poor fetal health. Accurate results are based on the use of a monitoring system reviewed by your health care team, regardless of how many weeks of gestation your baby is.

If these accelerations or decelerations are not occurring at the stages they should be, or if they are prolonged, it may mean a number of things, such as the umbilical cord is compressed and blood flow to the baby has been slowed. Usually, a simple method used, such as changing your labor position, may improve the situation and increase blood flow. If, when monitoring the birth, the fetal heart rate results indicate that your baby may be in danger (such as an irregular beat), your doctor may make a decision to rupture the amniotic sac to accelerate delivery, or recommend an operative vaginal delivery or a cesarean section.

Is it possible to determine my baby’s sex by the fetal heart rate?

According to an old wives’ tale, if your baby’s fetal heart rate is greater than 140 bpm, the baby is female. If the fetal heart rate is below 140 bpm, it is a boy. Of course, superstition is not used to test fetal monitoring – if it were this easy to tell the baby’s gender, obstetricians would be out of a job! Your baby’s fetal heart rate has nothing to do with his gender. A study from the 1980’s disproved this heart rate “myth” after examining more than 10,000 babies; a secondary study conducted in 2006 would help reconfirm what scientists already knew: there is no relationship between fetal heart rate and the sex of the baby. An ultrasound during pregnancy is usually the easiest and most accurate way to make sure.

One accurate predictor is the use of ultrasonography, which identifies the baby’s sex by examining fetal anatomy depending on the trimester. Find out from your doctor when you’ll be able to see your baby’s sex on ultrasound.

When You Can Find Out Baby’s Sex

The main reason for having a baby gender ultrasound is to determine the health and well-being of your baby. Having said that, it is only natural that the parents would want to learn her baby s sex as well. An amniocentesis is a medical, prenatal procedure that is used to test for risk of fetal abnormalities (birth defects) like down syndrome, cystic fibrosis or spina bifida; an amniocentesis can tell you whether your baby has a genetic disorder by analyzing fetal cells that are found in amniotic fluid, from about 15 weeks of pregnancy. You can learn more on amniocentesis and the associated risk in this article. Similarly, chorionic villus sampling (CVS) is another prenatal test that is used to detect birth defects in pregnant women, including genetic diseases.

While prenatal screening tests, including blood tests and ultrasounds, can tell parents if their baby has a riskof a disorder, wanting to know your baby s gender and when it can be identified is probably one of the most common first requests at an ultrasound appointment. In addition to ultrasounds, it is possible to know if you’re having a boy or girl through a urine test or through sexing, but for the purposes of this article, we will examine sexing through ultrasound.

Unfortunately, there isn’t one easy answer for moms-to-be. Identifying the baby s genitalia depends on a number of factors. For example, the fetal position can make it difficult, if not impossible, to see the baby’s gender. The appearance of genitalia (i.e. penis or clitoris) will also depend on your baby’s gestational age. Currently, we know that the diagnosis of sex is inaccurate until the 12th week of pregnancy — after the 13th week of pregnancy, it can reach 99 to 100% accuracy.

The gestational age tables vary from population to population, so it is preferable to use the size of the fetus (not the gestational age) to determine whether your baby is a boy or a girl. Fetuses over 72 mm that are in the right position with a clear image on the monitor will allow your technician / doctor to reveal the sex with nearly 100% accuracy.

How does the doctor know the baby’s sex?

A sonographer specializes in the use of ultrasonic (sound waves) imaging devices to produce diagnostic images, scans, videos or three-dimensional renderings of anatomy. During your pregnancy, an ultrasound technician should be able to look for and see the genital tubercle from as early as the 13th week – the structure that will develop into a penis for a boy and a clitoris for a girl. The site and positioning of the tubercle in a girl is horizontal (parallel to the spine), while in a boy it is vertical before developing into an penis (perpendicular to the spine), as shown in the image below. Medical ultrasounds are about 99 percent accurate in determination of the baby s gender.

Below is a slightly adjusted image of the genitalia to show the difference between boys and girls during pregnancy (not always easy to identify on ultrasound). Contrary to popular belief, the fetus’ heart rate does not determine the sex of your baby.

Baby gender on ultrasound
How to identify baby’s gender on ultrasound

What can impede finding out the sex of your baby?

In addition to the baby’s position during pregnancy and the size of the fetus, there is more than one medically reviewed factor that affects baby gender identification, including:

  • Sign of maternal obesity
  • Site of previous abdominal surgeries
  • Weeks of pregnancy
  • Risk of fetal abnormality
  • Uterine positioning
  • Fetal positioning
  • Quality of the medical ultrasound device used

If your doctor has said he is having difficulty determining the sex of your baby during an ultrasound, it might be too early and it’s probably best to have the test done on another day. Remember that you will get additional ultrasounds between 11 and 14 weeks to measure the nuchal translucency. When you schedule this exam, you can measure nuchal translucency at that time and have at least a good idea of your baby s gender, in addition to important information about your baby s well-being.

CAUTION: The correct time to measure nuchal translucency is when the fetus is between 45 and 84 mm in length from head to buttocks. So it’s important not to schedule your exam at the end of 14 weeks, as the fetus may have passed the appropriate measurements to determine nuchal transparency. 

When can parents find out the baby s gender?

Look at your calendar to count the gestational age. Note that not every month has 4 weeks; as the interval between 13 and 14 weeks is very short, this small difference can cause you to miss the one window that measures nuchal translucency. If you are in doubt, read this article to find our gestational age calculator. You may also like this article on converting months to weeks to make sure said calculations are accurate.

Until you find out the sex of your baby, you may decide not to get baby clothes for now. Regardless of when you determined the sex of your baby, you’ll want to wait for a second test in the list of ultrasounds (called the morphological exam), between 20 weeks and 24 weeks. After the prenatal morphological examination results, your ultrasound technician can confirm the sex of your baby with 100 percent accuracy — go ahead and find his first trousseau! 

Is there a trick to choosing the sex of the baby before becoming pregnant?

Throughout history, women have done peculiar things in the name of pre-determining the gender of their baby. Despite old wives tales, in naturally conceived pregnancies early gender selection is not possible; there is no universal sign that will ensure your baby has a penis, no food that will determine the sex of your child. Your ob gyn cannot ‘make’ you conceive a baby boy or get a ‘girl ultrasound’ with exclusively ‘female sound waves’. There is no medically reviewed, scientific sign that your lifestyle choices will affect if you’re having a boy or girl. From time to time we hear that there may be a difference in the speed of the sperm that carries the X chromosome and the sperm that carries the Y chromosome. It is said that this, in theory, may affect the gender, but is not a prediction; there is no scientific evidence used to support this claim, and no way for your ob gyn to test it (through blood tests, etc.) So having sex farther or closer to ovulation is not an accurate way to determine or learn the sex.

What are the signs of labor?

Wouldn’t it be wonderful if there was a timer that told you when labor starts? During their pregnancy, any pregnant women wonder what it will feel like, how long it will take and if they’re actually in labor, or if it’s just a false alarm (i.e. Braxton-Hicks contractions). Everyone’s pregnancy is different; similarly, everyone’s delivery experience is different. Knowing the signs of labor will help prepare you to get ready and meet your new baby.

Woman with signs of labor going to the hospital

Braxton Hicks Contractions

Since mid-pregnancy, you may have experienced some irregular labor contractions, known as Braxton-Hicks contractions. These are just “training” contractions, but as your pregnancy comes close to an end, these contractions get progressively longer and have a shorter interval; you will definitely notice the signs of active or “true” labor, a sure sign that your baby is ready to come. The early phase, known as prodromes of labor, can begin a few days or weeks before active labor.

What are the early signs of labor?

During actual labor, the contractions are quite rhythmic, occurring every 3 to 4 minutes and lasting at least 30 to 70 seconds each. If you’d like to track the progress of your labor, lie back, relax and place your hand on your abdomen, near the dome-shaped uppermost, rounded part of the uterus, called theuterine fundus. When a contraction starts, you may notice the uterus will shift forward and harden. When you feel the contraction start, use a watch to time the duration of the contraction. Contractions may or may not be associated with pain. Depending on the intensity of the contractions and the sensitivity of the mother, contractions may be experienced anywhere from mild to intense pressure and discomfort. Labor contractions are usually localized to the lower part of the belly, but can also radiate to the lower back. Time your contractions for about 10 minutes; if you count at least 3 contractions within this time frame, and they get stronger and closer together, this is probably the most important indicator that you are in labor, and it’s time for your baby to come!

It is important to note that there are situations where the uterus might be stimulated and a few contractions may come in a row and get closer together, then cease after a period of rest, without the cervix dilating. Women experience this if, for example, they walk around for a while, if there are still has a few weeks to go before the due date, or if they are very stressed about their pregnancy. In this instance, they are experiencing false labor. If a patient is ever concerned, she should go to the hospital.

How can I be sure that I’m going into labor?

To make absolutely sure that you are in labor and ready to deliver your baby, you would ideally evaluate your contractions for longer than 10 minutes. We advise that if you have 3 contractions in 10 minutes, wait another 30 minutes and then do a new evaluation. If the contractions persist at regular intervals, and are fewer minutes apart, it is time for you to go to the hospital so that you can be evaluated by your doctor.

In addition to uterine contractions, there are other early signs of labor during your pregnancy that may indicate your baby is ready. It is best to contact your doctor or midwife if you experience any of the following:

  • A few days (or even weeks) before delivery, your belly will look like it has “dropped”. This is because the uterus is shrinking in size as your baby drops and prepares to enter the world. You may experience lower back pain as well.
  • The process of your baby settling or lowering into your pelvis just before labor is called lightening. Lightening can occur a few weeks or a few hours before labor. Because the uterus rests on the bladder more after lightening, some women get the need to urinate more frequently during the last part of their pregnancy.
  • During your pregnancy, in the days before labor you may feel a sudden burst of energy and get an increased drive to clean and organize in preparation for your baby. This can even happen weeks before the time your baby is due.
  • Your cervix will dilate open when labor begins, though you will need a vaginal exam to determine this. Do not examine your own cervix! If your cervix dilates, Make sure you get the right medical advice from a doctor or midwife. They will advise if you cervix is dilated at 10 centimeters, or how much time you’ll have before that occurs.
  • When your cervix does begin to dilate, you may lose your mucus “plug”, a phlegm-like substance that seals the uterine cavity. The mucus plug may be followed by a “bloody show”, or blood-tinged vaginal discharge (there is no pain when this occurs). Mucus may present as light pink, brown or bright red.
  • You feel your water breaking. Many women feel like they’ve accidentally peed themselves, when in fact it’s amniotic fluid emptying from the amniotic sac; when your water breaks, it’s a definite sign to get ready for labor. For some women, they may not feel their water break at all, and have to rely on other signs of labor such as regular contractions that are several minutes apart.
  • When labor starts, you may feel like you have to vomit, especially while you’re having regular contractions and/or lower back pain. This may mean your baby is getting ready to come.
  • You see your baby s head. This is unusual, but some women don’t know they’re in labor, think they’re in false labor, or are unaware that they are experiencing the signs of labor. If your baby is crowning, and you’re on or near your due date, this is a key differentiator between true labor and false labor.

If you’re still unsure, if your water breaks, or even if you think you might be having false labor contractions, call your doctor or midwife, and/or get to the hospital as soon as labor starts so that an obstetrician can properly assess your pregnancy and your baby. If you are experiencing any signs of active labor such as bloody show, water breaking or another sign of labor and you are less than 37 weeks into your pregnancy, call your doctor as you may be in premature labor. In this instance, you will get an exam to assess the labor signs, as well as the risks of preterm labor, in addition to the second trimester morphological exam.

In the event of preterm labor, it is essential to arrive at the hospital as soon as possible to be medically reviewed so that the doctor can inhibit labor contractions or prescribe medication to rapidly mature the baby’s lungs. If you are in early labor you may be at risk.

How long will my labor last?

The duration of labor varies, but typically lasts between 12 to 24 hours. However, many women include the hours before labor, known as the prodromal labor phase — contractions that begin before true labor. Unlike Braxton-Hicks contractions, which help your uterus prepare for active labor, your cervix can slowly dilate or efface during prodromal labor. If we include this phase, labor can last up to a few days.

What can I do to encourage true labor?

Even in today’s age, the mechanism by which true labor begins is not fully understood. Most of the time, it is difficult to predict when the true labor will start, even if we know the due date (or the mother’s water breaks). Toward the end, when the baby is ready, she will go into labor, however there are instances that can help labor along:

  • Short walks or gentle yoga (which may feel good whether or not you’re in labor)
  • Having sex. This can cause the uterus to contract in 3 different ways: 
  • Through orgasm
  • Through the release of oxytocin (a hormone that makes the uterus contract)
  • Through semen, which can also cause contractions
  • Nipple stimulation. Small (gentle) pinches can also help release oxytocin. If you have previously breastfed a baby, you’ll remember experiencing cramps while nursing. This is due to the release of oxytocin triggered by the nipple stimulation.

If you have additional questions about the signs that labor have begun, or about whether you’re going into labor (or having false labor contractions), call your doctor or midwife to discuss your concerns.

Pregnancy Due date calculator

How do I use the Pregnancy Due Date Calculator?

Our online pregnancy due date calculator allows you to determine how many weeks old your baby is in utero (also known as your gestational age). The easiest way to use the pregnancy due date calculator is to simply enter the first day of your last period. If you don’t know when the first day of your last menstrual period was, your baby’s age can be calculated in five different ways. 

  1. Estimated Due Date (or EDD): If you know your baby’s expected delivery date, you can enter that day on the calculator and it will inform you of your baby’s current gestational age, the likely date of conception and other important information about your pregnancy. Important to note: PDD is not the day you’ve scheduled for delivery, the expected date of birth is the day your baby turns 40 weeks old.
  2. Last Menstrual Period (or LMP): The first day of your last menstruation is the most commonly used parameter to determine your baby’s gestational age. With this information, we can better understand your menstrual cycle and determine all the important milestones of your pregnancy.
  3. Date of a previous exam: Use this if you do not know when your last menstrual date was or when your probable delivery date is. In this instance, it is not possible to calculate using your menstrual cycle, so we’ll need to perform an ultrasound to be certain. Important to note: You should always use the first exam that was performed during this pregnancy for the calculation to be accurate; the earlier it is, the lower the margin of error for the ultrasound. If you choose to use this parameter for the calculation, you will need to enter the gestational age that was estimated on that exam, in addition to the date on which the exam was performed. For example, if you took an exam on the 10th of May, your baby’s estimated gestational age would be 8 weeks and 3 days. In this case, you should use the value of “10/05” in the “Date of a previous exam” field for the calculation, and in gestational age you must enter “8” weeks and “3” days.
  4. Transfer date: If you’ve gone through assisted reproductive technology cycles, you can calculate your due date more precisely using your IVF (in vitro fertilisation) transfer date.
  5. Conception date: If you happen to know precisely when you conceived, you can use this method to estimate your gestational age. Bear in mind that very few expectant moms know exactly when they conceived.

If the dates of your pregnancy are still causing you confusion, please consult your prenatal portfolio, where you will easily find all the information about your pregnancy. The due date based on your last period is calculated based on a normal menstrual cycle length. The average cycle length is 28 days, but can range anywhere from 24 to 38 days. 

Conception usually occurs around 14 days after the first day of your last period. The due date of your baby is calculated by adding 280 days to the first day of your last menstrual period. That is because the average length of human gestation is 40 weeks (or 280 days) from the first day of your last period.

I don’t know how to calculate gestational age in weeks. Can I use months instead?

No. Technically, the “correct” way to calculate gestational age is in weeks. Using months is an inaccurate way to count your pregnancy time. Months do not have the same number of days, and while there may only be a 1-day difference from one month to the next, adding that discrepancy to a 9-10 month time span would make a considerable difference. There are many reasons to count gestational age in weeks rather than months, and we have linked two posts on the subject below:

  • How is Gestational Age (Duration of Gestation) calculated?
  • Gestational Age in Months

I’m still trying to get pregnant. How do I use the calculator?

In this instance, you do not need the pregnancy due date calculator, but use the Fertile Period Calculator instead. With this calculator, it is possible to determine the probable day of your ovulation based on the characteristics of your menstrual cycle. This will allow you to determine when your chances of becoming pregnant are greatest.

Reference: Calculadora de Idade Gestacional | Fetalmed