Second Trimester Heart Rate Changes

The fetal heart rate will change during the second trimester, just as it changes throughout the various stages of pregnancy. In fact, the fetal heart rate can change on a moment-by-moment basis, in response to various stimuli or various conditions that can be affecting your baby. While your baby’s heart rate does tend to spike briefly around the age of ten weeks of pregnancy, by the time that the second trimester rolls around, your baby’s heart rate will not change much until after your baby is born.

The fetal heart rate can, typically, be heard at around eight to ten weeks of pregnancy, depending on the mother’s body size and the method used to find the fetal heart rate, whether a transvaginal ultrasound or a Doppler or some other method. At around the tenth week of pregnancy, roughly three weeks before the second trimester begins, the fetal heart rate will peak at around 175 beats per minute. By week fifteen, which is during the very early part of the second trimester, the fetal heart rate will have dropped down to around 140 beats per minute.

It was once thought that the fetal heart rate could predict your baby’s gender. It was thought that, if a baby’s heart rate was under 140 beats per minute that it would be a boy, and that if it was over 140 beats per minute it would be a girl. The theory behind this idea was that, because women usually have a higher metabolic rate than men, that unborn girls would have a slightly higher pulse rate than unborn boys. However, most research does seem to disprove this idea, and demonstrate that there is not necessarily a connection between the fetal heart rate and the gender of your baby.

If you have concerns about your fetal heart rate, you should speak with your health care provider. Your health care provider can help to interpret what a high or a low fetal heart rate might mean, as well as help to figure out if it indicates some sort of a problem that will need to be addressed.

No Baby Gender Prediction Test is Perfect

Wondering about the gender of the baby you’re carrying is as natural as breathing. Any expectant mother who tells you she isn’t curious about whether she’s having a boy or a girl either already knows (or thinks she knows) or is lying.

These days, we expect to know the gender of our babies with relative certainty by the midway point of the pregnancy. Ultrasound technology has advanced to the point that we can know with 90% accuracy whether we’re carrying a boy or a girl at 20 weeks gestation. That’s great, except:

  • No one really wants to wait 20 weeks to find out
  • 90% accuracy still means 1 in 10 will get wrong information about baby’s gender

Some are content to wait and wonder, but many want to know sooner. Since moving the ultrasound up isn’t generally an option, we’re left with using traditional baby gender prediction methods or ponying up to buy commercially available baby gender tests.

Traditional Baby Gender Prediction Methods

Beliefs about traditional baby gender prediction methods range from blind faith to dismissing them as old wives’ tales. Blind faith in a scientifically unproven prediction method probably doesn’t give you any better chances of accurately predicting your baby’s gender than flipping a coin and assigning heads to “it’s a boy” and tails to “it’s a girl.”

Still, it’s not unreasonable to suggest that there might be a very good reason why some old wives’ tales have stuck around long enough to become part of our oral tradition. Maybe there’s some truth to them. Many hold firmly to beliefs such as:

  • Where you’re carrying the baby (high or low) indicates the baby’s gender
  • Suspending your wedding ring on a string over your belly and observing whether it swings back and forth (it’s a boy!) or in circles (it’s a girl!) can predict your baby’s gender
  • Mixing your urine with Draino can predict your baby’s gender: If the color changes, buy blue paint, if it stays the same, invest in pink

At the very worst, these methods offer a 50/50 chance of predicting your baby’s gender and can be fun.

Other Medical Baby Gender Prediction Methods

Other than ultrasound, the two main medical gender prediction methods are amniocenteses and CVS testing. Unfortunately, both of these are more invasive and carry more risk than ultrasound, so doctors won’t order them just to satisfy your curiosity. Generally, you need to have a serious risk factor in your pregnancy before a doctor will order one. These tests are about 99% accurate.

Of course, there is no perfect gender prediction test. Even the most accurate and scientific tests still have the potential to get it wrong. Who knows? Maybe that’s to keep us guessing, if only a little, until the big day finally comes.

Baby Gender Prediction Based On Baby’s Heart Rate

One of the popular theories on baby gender prediction is based on the baby’s heart rate.

The theory states that if your baby’s heart rate was 140 beats per minute and above, you would be having a girl. If the heart rate was under 140 beats per minute, then you would be having a boy.

While this would be a quick and easy baby gender prediction method, there is actully no evidence that this theory is accurate. There is recent study, “Sex, Heart Rate, and Age” from Terry J. DuBose, M.S., RDMS; Director Diagnostic Medical Sonography Program at the University of Arkansas for Medical Sciences, which indicates there is no correlation between fetal heart rate and the gender of the baby.

How Ultrasounds Predict Gender

An ultrasound is one of the most reliable ways to tell your baby’s sex. As a matter of fact, an ultrasound may be the only way, short of something like genetic sampling or amniocentesis, that you will be able to tell your baby’s sex with any degree of certainty. Understanding how an ultrasound can be used to tell your baby’s sex is an important part of knowing how reliable the ultrasound will be.

An ultrasound relies on making a visual representation of what is going on inside of your womb. Using an ultrasound, you can usually see your baby’s heartbeat at around 8 weeks of pregnancy, for example. An ultrasound is also used to measure your baby, and to track your baby’s growth. An ultrasound may be used to try to detect if there are any abnormalities with the way that your baby is forming, as well. And, as has been said before, an ultrasound can indeed be used to tell your baby’s sex.

How an ultrasound is used to tell your baby’s sex relies, at least in part, on the person operating the ultrasound, whether it is an ultrasound technician or whether it is your health care provider. The person operating the ultrasound will be able to tell your baby’s sex by looking for the presence of genitals. If the person that is operating the ultrasound can see a penis, she will predict that your baby’s sex will be male. Telling your baby’s sex when it is a girl, however, can be more difficult. If the person operating the ultrasound actually sees the labia on the ultrasound, your baby’s sex is obviously female. But if the person operating the ultrasound just doesn’t see a penis, it doesn’t mean for certain that your baby’s sex is male. As a matter of fact, without seeing the labia, most of the time the person operating the ultrasound will not tell you that your baby’s sex is female.

There are other factors that will tell whether the ultrasound is reliably telling your baby’s sex. First, the position of your baby can affect whether or not the genitals can be seen. Also, your baby’s age and size will play a role as well.

5 Popular Gender Prediction Methods



Even since couples have been having babies, they’ve wanted to figure out ahead of time whether they were having a baby boy or a baby girl. In today’s world, we have medical imaging which can predict a baby’s gender with a high degree of accuracy as early as the twelve weeks into the pregnancy (around the beginning of the second trimester). Still, most parents are curious and many are willing to try more traditional methods of gender prediction while they wait for the official results.

Here are some of the more popular traditional methods of gender prediction:

  1. Watch your cravings. Many people believe that the kinds of food you crave during your pregnancy will give you a hint as to whether you’re having a boy or a girl. Are you craving potato chips and pickles? Stock up on blue paint. Would you rather have chocolate and ice cream? Stick with pink.
  2. Mayan numerology. Lots of airplay has been given to Mayan predictions of the world’s end in December 2012, but they had a more useful legend for expectant parents. According to their tradition, if a mother’s age (in years) and the year of conception are both even or both odd numbers, you will have a girl. If one is even and the other is odd, you’ll have a strapping Mayan warrior.
  3. Zits are for girls. Some believe that you are more likely to break out in zits if you are having a girl. Traditionally, this is believed to be because that little cutie growing inside of you is stealing as much of your beauty as she can grab.
  4. His and Lows. One of the most widely accepted gender prediction methods is to simply look into a full length mirror and see whether you’re carrying the baby high or low. If your baby bump is low, it’s a bouncing baby boy. If you’re carrying higher, it’s a girl. Of course, by the time you can tell whether you’re carrying high or low, you can have the ultrasound technician give you a much more accurate prediction based on what kind of genitalia she sees.
  5. Chinese Prediction Calendar. When a prediction method is used for 7,000 years, there’s a chance there’s something to it. Many Chinese (and an increasing number of Westerners) swear by the Chinese gender prediction calendar, which used a mother’s age at the time of conception and the month the baby was conceived to predict babies’ gender.

Most gender prediction methods have their defenders who swear by them and detractors who think of them as fun but unscientific diversions. Even the worst gender prediction method has a 50% chance of success, though, and there’s certainly nothing wrong with being curious while you wait for the definitive answer.

Fetal Heart Rate: Can It Predict Gender?


When is an old wives’ tale not really an old wives’ tale? When the myth started in the scientific community.

There is a popular notion that you can predict the gender of your baby based on his or her fetal heart rate. Most proponents of this theory suggest that:

  • A fetal heart rate of 140 bpm (beats per minute) or higher indicates that you are carrying a baby girl.
  • A fetal heart rate of less than 140 bpm indicates that you are carrying a baby boy.

Many have dismissed this as an old wives’ tale. That hardly seems plausible, however, since we have only been able to monitor fetal heart rates in recent decades. Fetal heart rate monitoring made its debut in the 1960s. So, where did the idea get its start?

It turns out that it was the medical community itself that got this rumor started. While the technology for monitoring fetal heart rates was still fairly new, some doctors speculated that you may be able to determine a baby’s gender by its fetal heart rate. Studies were conducted, but were generally inconclusive. Still, it didn’t stop the theory from gaining widespread acceptance, especially outside of the scientific and medical community.

At least three studies (two in the United States and one in the United Kingdom) have been conducted which have shown that fetal heart rate cannot accurately predict a baby’s gender.

The studies showed that a number of factors determined babies’ fetal heart rates, including:

  • Gestational age. Between eight and ten weeks, your baby’s heart rate will generally be between 170 and 200 beats per minute. During your second trimester, your baby’s heart rate will generally be between 120 and 160 bpm.
  • Baby’s movement. When your baby is active and kicking about inside you, her heart rate will go up. When she’s resting, her heart rate will go down. In that respect, she’s no different than you are.

Unfortunately, the studies do not show any correlation between fetal heart rate (at any stage of gestation) and baby’s gender. In fact, they show fairly conclusively that you cannot predict a baby’s gender by his or her heart rate.


How to Predict Baby’s Gender the Chinese Calendar Way


One of the most ancient methods of predicting your baby’s gender is with a Chinese gender prediction calendar. This method has been used to help expectant mothers and fathers for thousands of years not only to determine whether they’re going to have a boy or a girl, but to help time their baby making activities so as to know when the best time is to conceive a boy or when the best time is to conceive a girl.

How it works

Chinese calendar gender prediction is based on two important factors: the age of the mother when the baby was conceived, and the month in which the baby was conceived.

The calendar relies on the lunar calendar, so you can’t simply use the Western calendar to make this determination. You need to know how old the woman is under the Chinese calendar, and know what Chinese lunar month the baby was conceived during.

Using the Chinese gender prediction chart

Once you have the mother’s age at the time of conception and the month of conception, it’s a matter of looking at the chart. Some combinations will result in a boy gender prediction, while others will result in a girl gender prediction.


The Chinese gender prediction calendar was, in ancient China, used exclusively by the royal families. In fact, it was invented for that purpose. The basic premise was to maximize the odds that royal families would conceive male heirs.

It wasn’t until after the fall of imperialism in China that the Chinese gender prediction calendar came to be used by ordinary people.

Potential errors

There are two common errors people make when attempting to use a Chinese gender prediction calendar: they either fail to use the Chinese (lunar) age of the mother or the lunar month. The other error has to do with miscalculating when exactly the baby was conceived.

Scientific methods

Chinese Gender Prediction calendars aren’t scientific, but they can be fun to use and talk about. Before you buy decorations, furniture, and clothing appropriate for a boy or a girl, you’re probably best off waiting for your 20-week ultrasound.

Dads Want Sons, Moms Want Daughters


Put this into the “you already guessed it” category, but some recent research shows that parents often have a preference – a significant preference, even – about the gender of their expected child.

In this survey, participants were asked what gender they’d prefer their firstborn to be, what gender they’d prefer the majority of their children to be, and what gender they would prefer if they were to only have one child.

What the researchers were surprised to find – which we may not be quite as surprised to find – is that men prefer sons, and women prefer daughters.

Evolutionary drive

In some ways, it’s easy to reason why men would want to have sons. After all, men have the possibility of keeping the family gene line going by potentially fathering more women than a single woman could bear. While in most cultures that actual practice wouldn’t be looked upon favorably, you can see where the drive comes from.

For women, however, it’s suggested that there is a more complex reasoning for wanting daughters. Women may have a desire to have the shared experience of pregnancy, or the strong bonds that are perceived to exist between mother and daughter.

Women, according to the researchers, have a “legacy drive” rather than a simple drive to procreate and keep the genetic line going.

Gender selection

There are a number of ways this plays out, of course. In some extreme cases, for example, there is the practice of female feticide, in which girls are aborted and boys are not. This isn’t entirely uncommon in certain countries like India and China. Yet, there is some evidence that it’s happening among certain cultural groups in North America, as well.

This type of gender selection goes way beyond simply trying to give yourself an edge in choosing your baby’s gender. Some ethicists make the case that it’s actually a form of discrimination against women, and if practiced on a large scale could lead to other sociological problems.

One solution proposed in Canada, for example, is to hold off revealing a baby’s gender until after 30 weeks of pregnancy, at which point abortion is no longer a legal option. 

How Accurate Is A Due Date?


A due date is, in reality, an educated guess by your physician based on your recollection of dates and, later during pregnancy, of your baby’s growth. The fact is your baby will arrive whenever she’s ready to arrive, not before or after. Most births don’t actually occur on the due date, believe it or not.

A healthy pregnancy is considered anywhere from 39 to 42 weeks. (Although full term is considered 37 weeks, many experts believe that babies have the best results in terms of health when delivered after week 38).

The due date prediction is fairly straightforward. Go back to the first day of your last menstrual period. Pregnancy typically lasts 280 days from that time until delivery. If you usually have a longer cycle than 28 days, you might deliver after your due date, and if yoru cycle usually is shorter, you might deliver a few days prior.

In addition to this sort of calculation, your health care provider might use other means to try to predict a more accurate due date. Using an ultrasound, your health care provider will take a measurement of various parts of your baby’s growth and development. The size of your baby during these ultrasounds, as well as the growth that your baby makes between ultrasounds, might prompt your health care provider to alter your due date, if the measurements don’t match up very well with the date calculated using the date of your last menstrual period.

Once you hit 40 weeks of pregnancy and become “overdue,” your health care provider will probably suggest some stress testing in order to make sure that your baby is still doing all right. If pregnancy goes much past your due date, your health care provider may suggest that you should have labor induced. On the other hand, if you were to go into labor before the 37th week of pregnancy, it is likely that your health care provider would like to be able to stop labor, and postpone it long enough for your baby to do some more developing.