Enter the heart rate measured during your ultrasound.
Boy or Girl? The Heart Rate Method Explained
Waiting to find out the gender of your baby is one of the most exciting parts of pregnancy. While modern medical technology like ultrasounds and NIPT blood tests offer high accuracy, old wives' tales and folklore methods remain incredibly popular for their fun and anticipation factor.
This Fetal Heart Rate Gender Prediction Calculator is based on one of the most enduring myths in pregnancy folklore: the idea that a baby's heart rate can indicate whether you are carrying a boy or a girl.
How the Calculation Works
According to this popular theory, the dividing line is typically set at 140 Beats Per Minute (BPM). The folklore suggests the following logic:
Over 140 BPM: It is predicted to be a Girl.
Under 140 BPM: It is predicted to be a Boy.
Medical Disclaimer: Please note that this calculator is for entertainment purposes only. Scientific studies have shown no significant difference between male and female fetal heart rates during the first trimester. Always consult your doctor or sonographer for accurate medical advice.
Interpreting Your Results
Understanding where your baby's heart rate falls on the chart can be fun to track throughout your pregnancy.
Heart Rate Range (BPM)
Folklore Prediction
Notes
Below 140
Boy
Often associated with a slower, steady rhythm.
Above 140
Girl
Often associated with a faster, galloping rhythm.
Exactly 140
Uncertain
Borderline range; could go either way.
Factors Affecting Fetal Heart Rate
Regardless of gender, a baby's heart rate changes naturally throughout pregnancy. It starts slow (around 80-100 BPM at 6 weeks), accelerates to roughly 170-200 BPM by weeks 9-10, and then gradually settles down to an average of 120-160 BPM for the remainder of the pregnancy.
Your baby's heart rate can also fluctuate based on:
Activity Level: Just like adults, a baby's heart rate increases when they are moving.
Gestational Age: The heart rate varies by week of pregnancy.
Maternal Conditions: Your own heart rate, stress levels, or caffeine intake can influence the reading.
Scientific Reality vs. Folklore
Several studies, including research conducted by Austin Radiological Association and others, have debunked the heart rate gender myth. They found that while girl fetuses might have a statistically insignificant higher heart rate during labor, there is no reliable difference during the first and second trimesters when most parents are eager to know.
Other Popular Gender Prediction Myths
If you enjoyed checking the heart rate method, you might also be familiar with these other old wives' tales:
Morning Sickness: Severe nausea is often linked to girls, while little to no sickness is linked to boys.
Cravings: Craving sweets suggests a girl, while craving salty or savory foods suggests a boy.
Carrying High or Low: Carrying high is said to be a girl, while carrying low is said to be a boy.
Use this tool as a fun way to engage with your pregnancy journey, but rely on your 20-week anatomy scan for the big reveal!
function predictGender() {
// 1. Get input value
var bpmInput = document.getElementById('fetalBpm');
var bpmValue = parseFloat(bpmInput.value);
var resultContainer = document.getElementById('result-container');
var headerDiv = document.getElementById('predictionHeader');
var textDiv = document.getElementById('predictionText');
// 2. Clear previous classes
resultContainer.className = ";
// 3. Validation Logic
if (isNaN(bpmValue) || bpmValue === 0) {
alert("Please enter a valid heart rate value.");
resultContainer.style.display = "none";
return;
}
if (bpmValue 250) {
alert("This heart rate seems unusually high or low for a viable pregnancy. Please verify the number.");
resultContainer.style.display = "none";
return;
}
// 4. Calculation Logic (Old Wives' Tale Logic)
var gender = "";
var explanation = "";
var cssClass = "";
// Threshold is typically 140 BPM
if (bpmValue > 140) {
gender = "It's a Girl!";
explanation = "According to folklore, a heart rate above 140 BPM indicates you are carrying a baby girl.";
cssClass = "result-girl";
} else if (bpmValue < 140) {
gender = "It's a Boy!";
explanation = "According to folklore, a heart rate below 140 BPM indicates you are carrying a baby boy.";
cssClass = "result-boy";
} else {
// Exactly 140
gender = "Too Close to Call!";
explanation = "A heart rate of exactly 140 BPM is right on the borderline. It could be either a boy or a girl according to this method.";
cssClass = "result-neutral";
}
// 5. Display Result
headerDiv.innerHTML = gender;
textDiv.innerHTML = explanation;
resultContainer.className = cssClass; // Apply pink, blue, or neutral styling
resultContainer.style.display = "block";
}