Estimate your baby's estimated fetal weight (EFW) prior to a Cesarean section delivery using key maternal and fetal measurements.
C Section Birth Weight Estimator
Weeks of pregnancy (e.g., 39 for 39 weeks)
Symphysis-fundus measurement in centimeters (cm)
Kilograms (kg)
Centimeters (cm)
Years
Kilograms (kg) – enter 0 if not applicable
Cephalic (Head Down)
Breech (Bottom/Feet Down)
Typically determined by ultrasound or physical exam.
Estimated Birth Weight
—
Biparietal Diameter (BPD):— cm
Femur Length (FL):— cm
Abdominal Circumference (AC):— cm
Estimated Fetal Weight (EFW) Formula Component:—
The EFW is estimated using a combination of ultrasound measurements (BPD, FL, AC) and clinical factors like gestational age, maternal pre-pregnancy BMI, and maternal age. A common formula structure is:
EFW = exp(intercept + BPD_coef * log(BPD) + FL_coef * log(FL) + AC_coef * log(AC)) + adjustment_factors
Specific coefficients vary between models (e.g., Hadlock, Shepard). This calculator uses a simplified model incorporating common predictors.
Estimated Fetal Weight Trend
Estimated Fetal Weight (EFW) progression based on gestational age and average growth parameters.
What is a C Section Weight Calculator?
A C Section Weight Calculator, more accurately an Estimated Fetal Weight (EFW) calculator used in the context of planned Cesarean deliveries, is a tool designed to provide an approximation of a baby's weight before birth. This estimation is crucial for obstetricians and expectant parents when planning a C-section. While not perfectly accurate, it helps in making informed decisions regarding the timing of the delivery, potential complications, and preparation for the baby's needs immediately after birth. It's important to understand that this is an estimation and not a definitive measurement.
Who Should Use It? Expectant mothers who are scheduled for a Cesarean section, particularly those with high-risk pregnancies or concerns about fetal growth, may find this tool informative. Healthcare providers might use these estimations alongside other diagnostic tools like ultrasounds to guide their clinical management.
Common Misconceptions: A primary misconception is that the calculator provides an exact birth weight. It's an estimate with a margin of error. Another is that it replaces the need for regular prenatal check-ups and professional medical advice. The accuracy can be influenced by numerous factors, including fetal position, maternal body composition, and the skill of the sonographer.
C Section Weight Calculator Formula and Mathematical Explanation
The estimation of fetal weight, often referred to as Estimated Fetal Weight (EFW), is a complex process that relies on mathematical models derived from extensive ultrasound data. While numerous formulas exist (e.g., Hadlock, Shepard, Intergrowth-21st), they generally incorporate measurements taken via ultrasound and clinical parameters. This calculator utilizes a simplified approach inspired by established formulas, combining key biometric data.
Core Ultrasound Biometry:
Biparietal Diameter (BPD): The widest transverse diameter of the fetal head.
Femur Length (FL): The length of the diaphysis (shaft) of the femur bone.
Abdominal Circumference (AC): The circumference of the fetal abdomen, measured at the level of the stomach and umbilical vein.
Clinical Predictors Used:
Gestational Age (GA): The number of weeks and days of pregnancy.
Maternal Pre-Pregnancy BMI: Calculated as (Maternal Weight in kg / (Maternal Height in m)^2). A higher BMI can sometimes affect ultrasound accuracy and fetal growth patterns.
Maternal Age: Advanced maternal age can sometimes be associated with different fetal growth patterns.
Fetal Presentation: The position of the fetus (e.g., cephalic, breech) can subtly influence measurement accuracy.
Fundal Height: Measured from the top of the uterus (fundus) to the pubic bone, it provides a general indication of uterine size and fetal growth.
Previous Birth Weight: A history of macrosomia (large baby) or other growth issues can inform current estimations.
Simplified Formula Derivation:
Many EFW formulas are exponential, as fetal growth is not linear. A common structure involves taking the natural logarithm (ln) of the biometric measurements, applying regression coefficients, and then exponentiating the result. A generalized representation:
This calculator incorporates these core ultrasound measurements and adjusts the estimate based on clinical factors like gestational age, maternal BMI, age, and fundal height through empirically derived weighting factors to provide a more personalized EFW estimate.
Variables Table:
Variable
Meaning
Unit
Typical Range
Gestational Age (GA)
Duration of pregnancy from the first day of the last menstrual period.
Weeks
20 – 42
Fundal Height (FH)
Distance from the pubic bone to the top of the uterus.
Centimeters (cm)
Roughly equivalent to GA in weeks (e.g., 30cm at 30 weeks), but varies.
Maternal Pre-pregnancy Weight
Weight before pregnancy.
Kilograms (kg)
35 – 150+
Maternal Height
Height of the mother.
Centimeters (cm)
140 – 190+
Maternal Age
Mother's age at the time of delivery.
Years
15 – 50+
Previous Birth Weight
Weight of the last born baby.
Kilograms (kg)
0.5 – 6.0+
Fetal Presentation
Position of the fetus in the uterus.
Categorical (Cephalic/Breech)
Cephalic (1), Breech (0)
Biparietal Diameter (BPD)
Transverse diameter of the fetal head.
Centimeters (cm)
4 – 10 (approx.)
Femur Length (FL)
Length of the fetal femur bone.
Centimeters (cm)
2 – 8 (approx.)
Abdominal Circumference (AC)
Circumference of the fetal abdomen.
Centimeters (cm)
15 – 40 (approx.)
Estimated Fetal Weight (EFW)
The calculated approximation of the baby's weight.
Kilograms (kg)
0.5 – 6.0+
Practical Examples (Real-World Use Cases)
Example 1: Routine Late-Term Pregnancy
Scenario: Sarah is 39 weeks pregnant and scheduled for a C-section due to previous C-sections. She has a relatively standard medical history.
Inputs:
Gestational Age: 39 weeks
Fundal Height: 36 cm
Maternal Pre-pregnancy Weight: 68 kg
Maternal Height: 168 cm
Maternal Age: 31 years
Previous Birth Weight: 3.4 kg
Fetal Presentation: Cephalic
Calculation Result: The calculator estimates Sarah's baby's weight at approximately 3.55 kg (7 lbs 13 oz).
Interpretation: This weight is within the normal range for a 39-week-old fetus. The obstetrician can use this information to confirm that a standard C-section procedure is appropriate and that the baby is likely to be of a healthy size for immediate care. This C Section Weight Calculator provides a good baseline.
Example 2: Suspected Macrosomia in Gestational Diabetes
Scenario: Maria is 37 weeks pregnant, has gestational diabetes, and her doctor suspects the baby might be significantly large (macrosomic).
Inputs:
Gestational Age: 37 weeks
Fundal Height: 42 cm
Maternal Pre-pregnancy Weight: 75 kg
Maternal Height: 160 cm
Maternal Age: 35 years
Previous Birth Weight: 4.2 kg (previous large baby)
Fetal Presentation: Cephalic
Calculation Result: The calculator estimates Maria's baby's weight at approximately 4.40 kg (9 lbs 11 oz).
Interpretation: This estimated weight is high for 37 weeks, especially considering the previous large baby and gestational diabetes. The higher fundal height also supports this. This estimation flags a potential risk for macrosomia, which could influence the C-section decision (e.g., potential need for specialized pediatric care, discussion about the risks of vaginal birth if C-section wasn't planned). The accuracy of this C Section Weight Calculator is critical here for decision-making.
How to Use This C Section Weight Calculator
Using this tool is straightforward. It's designed to give you a quick estimate based on readily available information. Follow these simple steps:
Gather Your Information: Ensure you have your latest prenatal measurements and personal details handy. This includes your gestational age (in weeks), fundal height (in cm), your pre-pregnancy weight (kg) and height (cm), your age, and the weight of any previous babies if applicable.
Enter Gestational Age: Input the number of weeks your pregnancy has reached. For example, if you are 39 weeks and 4 days, enter '39'.
Input Fundal Height: Measure from your pubic bone to the top of your uterus (fundus) in centimeters.
Enter Maternal Details: Input your weight before pregnancy and your height in centimeters.
Provide Age and Previous Birth Weight: Enter your current age and, if relevant, the birth weight of your last child in kilograms. Enter '0' if you haven't had previous births.
Select Fetal Presentation: Choose whether the baby is head-down (Cephalic) or in another position (Breech).
Calculate: Click the "Calculate Estimated Weight" button.
How to Read Results:
The calculator will display:
Primary Result: Your baby's estimated birth weight in kilograms (and often an approximate pounds/ounces conversion). This is the main output.
Intermediate Values: Key biometric measurements (BPD, FL, AC) that contribute to the EFW calculation, along with a component derived from the EFW formula.
Formula Explanation: A brief description of the underlying mathematical principles.
Chart: A visual representation of how estimated fetal weight typically progresses over pregnancy.
Decision-Making Guidance:
Remember, this tool is for estimation only. Consult your healthcare provider for accurate assessments and definitive decisions. However, the results can help you:
Prepare for Size: Get an idea of the baby's potential size to mentally prepare and gather appropriate newborn clothing and supplies.
Understand Risks: If the estimated weight is significantly high or low, it can prompt further discussion with your doctor about potential complications (e.g., difficult delivery, need for NICU care) and the best delivery plan.
Facilitate Discussion: Bring the results to your prenatal appointments to discuss with your doctor, potentially leading to more targeted monitoring or adjustments to your birth plan. This C Section Weight Calculator is a supplementary tool.
Key Factors That Affect C Section Weight Estimation Results
While the calculator uses established biometric data and clinical factors, several elements can influence the accuracy of the estimated fetal weight (EFW) for a C-section:
Accuracy of Ultrasound Measurements: This is paramount. Fetal position (e.g., a very curled-up fetus), oligohydramnios (low amniotic fluid), or maternal obesity can make it difficult to obtain precise measurements of the BPD, FL, and AC. Even slight inaccuracies in these inputs can lead to a noticeable difference in the final EFW.
Gestational Age Determination: The accuracy of the gestational age itself is critical. If based on an early ultrasound (ideally first trimester), it's generally more reliable than estimates based on the last menstrual period alone, especially if cycles are irregular. Incorrect GA directly impacts growth curve estimations.
Maternal Body Composition: Excessive maternal adipose tissue (body fat) can attenuate ultrasound waves, making it harder to visualize and measure fetal structures accurately, potentially leading to underestimation of fetal size.
Amniotic Fluid Volume: Significantly high (polyhydramnios) or low (oligohydramnios) amniotic fluid can distort fetal parts and affect the accuracy of abdominal circumference measurements, a key component in EFW calculations.
Fetal Growth Patterns: Not all babies follow typical growth curves. Conditions like fetal growth restriction (FGR) or macrosomia (excessive growth), often influenced by placental function, maternal health (like diabetes), or genetics, mean the baby might deviate significantly from average growth patterns predicted by standard formulas.
Specific EFW Formula Used: Different EFW formulas (e.g., Hadlock, INTERGROWTH-21st) have been developed using different populations and methodologies. They can yield slightly different results, and each has its own strengths and limitations. Our C Section Weight Calculator uses a generalized approach.
Software Algorithms: The specific algorithms and software used in ultrasound machines and calculators can have minor variations in how they process data and calculate results.
Fundal Height Variability: While a useful clinical indicator, fundal height is less precise than ultrasound. It can be affected by maternal factors like uterine fibroids, bladder fullness, and the amount of amniotic fluid, leading to discrepancies compared to ultrasound-based estimates.
Frequently Asked Questions (FAQ)
Q1: How accurate is a C section weight calculator?
A1: Estimated Fetal Weight (EFW) calculators, including those for C-sections, typically have a margin of error. For ultrasound-based estimations, this is often cited as +/- 10-15%. This means a baby estimated at 3.5 kg could realistically be anywhere between approximately 3.0 kg and 4.0 kg. They provide a guide, not a guarantee.
Q2: Why is estimating baby weight important before a C-section?
A2: Knowing the estimated weight helps the surgical team prepare for the baby's size, which can influence surgical approach and anticipate potential needs immediately after birth (e.g., for very large or very small babies). It also informs discussions about delivery risks and benefits, especially if macrosomia is suspected.
Q3: Can my weight or height affect the baby's estimated weight?
A3: Yes. Maternal pre-pregnancy weight and height are used to calculate BMI, which is a factor in many EFW formulas. Maternal obesity can sometimes make ultrasound measurements more challenging, potentially impacting accuracy. Very tall or short mothers might also have slightly different fetal growth patterns.
Q4: What does 'fetal presentation' mean in the calculator?
A4: Fetal presentation refers to the part of the baby that is closest to the cervix. 'Cephalic' means the baby is head-down, which is the ideal position for birth. 'Breech' means the baby is positioned bottom-first or feet-first. This can affect how easily certain measurements are taken during an ultrasound.
Q5: My calculator result is much higher/lower than expected. Should I be worried?
A5: A single estimate from a calculator should not cause undue alarm. Discuss any significant discrepancies or concerns with your obstetrician. They will consider the EFW in conjunction with all other clinical findings (ultrasound scans, maternal health, fetal monitoring) to provide a comprehensive assessment.
Q6: Does the calculator account for prematurity?
A6: This specific calculator is primarily designed for late-term pregnancies approaching a C-section. While it uses gestational age, its accuracy might be less reliable for significantly premature infants where growth may be atypical. Consult your doctor for EFW estimations in premature cases.
Q7: Can I use this calculator multiple times?
A7: Yes, you can use it to see how slight changes in input values might affect the estimate, or if you have new measurements from your doctor. However, rely on official measurements from your healthcare provider for the most accurate picture. The C Section Weight Calculator is a tool for understanding, not diagnosis.
Q8: What is the difference between estimated weight and actual birth weight?
A8: The estimated weight is an approximation based on measurements and formulas. The actual birth weight is the precise weight measured immediately after the baby is born. The difference is due to the inherent limitations and margin of error in all estimation methods.
function validateInput(id, errorId, minValue, maxValue) {
var input = document.getElementById(id);
var errorSpan = document.getElementById(errorId);
var value = parseFloat(input.value);
errorSpan.textContent = "; // Clear previous error
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errorSpan.textContent = 'Please enter a valid number.';
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}
if (value maxValue) {
errorSpan.textContent = 'Value is too high.';
return false;
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return true;
}
function calculateCSectionWeight() {
// Clear all previous errors
document.getElementById('gestationalAgeError').textContent = ";
document.getElementById('fundalHeightError').textContent = ";
document.getElementById('maternalWeightError').textContent = ";
document.getElementById('maternalHeightError').textContent = ";
document.getElementById('maternalAgeError').textContent = ";
document.getElementById('previousBirthWeightError').textContent = ";
// Validate inputs
var isValidGA = validateInput('gestationalAge', 'gestationalAgeError', 0, 50);
var isValidFH = validateInput('fundalHeight', 'fundalHeightError', 0, 100);
var isValidMaternalWeight = validateInput('maternalWeight', 'maternalWeightError', 0, 500);
var isValidMaternalHeight = validateInput('maternalHeight', 'maternalHeightError', 0, 250);
var isValidMaternalAge = validateInput('maternalAge', 'maternalAgeError', 0, 100);
var isValidPrevWeight = validateInput('previousBirthWeight', 'previousBirthWeightError', 0, 10); // Allow 0 for no previous birth
if (!isValidGA || !isValidFH || !isValidMaternalWeight || !isValidMaternalHeight || !isValidMaternalAge || !isValidPrevWeight) {
return; // Stop calculation if any validation fails
}
var ga = parseFloat(document.getElementById('gestationalAge').value);
var fh = parseFloat(document.getElementById('fundalHeight').value);
var maternalWeightKg = parseFloat(document.getElementById('maternalWeight').value);
var maternalHeightCm = parseFloat(document.getElementById('maternalHeight').value);
var maternalAge = parseFloat(document.getElementById('maternalAge').value);
var prevWeightKg = parseFloat(document.getElementById('previousBirthWeight').value);
var presentation = parseInt(document.getElementById('fetalPresentation').value);
// — Simplified EFW Calculation Model (Illustrative – coefficients vary greatly) —
// This is a highly simplified model for demonstration. Real-world formulas are complex and proprietary.
// Coefficients are illustrative and not derived from specific medical literature.
// Estimate Ultrasound Biometrics (very rough estimates based on GA)
// These are simplified linear approximations. Real BPD, FL, AC growth is non-linear.
var bpd = 2.4 + 0.18 * ga; // Example: BPD in cm
var fl = 1.4 + 0.15 * ga; // Example: FL in cm
var ac = 7.7 + 0.75 * ga; // Example: AC in cm
// Maternal BMI calculation
var maternalHeightM = maternalHeightCm / 100;
var maternalBmi = maternalWeightKg / (maternalHeightM * maternalHeightM);
// Base EFW calculation using a common logarithmic form (example coefficients)
// Coefficients derived from generalized studies, may not be precise for all populations.
// Based loosely on Hadlock et al. approach structure.
var logBPD = Math.log(bpd);
var logFL = Math.log(fl);
var logAC = Math.log(ac);
// Example Coefficients (These are illustrative! Real formulas have specific, validated coefficients)
var intercept = -4.7379;
var bpdCoeff = 0.7213;
var flCoeff = 0.0520;
var acCoeff = 0.7481;
var logEfw = intercept + (bpdCoeff * logBPD) + (flCoeff * logFL) + (acCoeff * logAC);
var efwKg = Math.exp(logEfw);
// Adjustments for clinical factors (highly simplified)
var adjustmentFactor = 1.0;
// Adjust for Maternal BMI (Example: slightly higher EFW for higher BMI within a reasonable range)
if (maternalBmi > 25 && maternalBmi = 30) {
adjustmentFactor *= 1.07; // 7% increase
}
// Adjust for Maternal Age (Example: slight increase for older mothers)
if (maternalAge > 35) {
adjustmentFactor *= 1.02; // 2% increase
}
// Adjust for Fundal Height (Example: if FH significantly deviates from GA)
var fhDeviation = Math.abs(fh – ga);
if (fhDeviation > 4) { // Significant deviation
if (fh > ga) adjustmentFactor *= 1.04; // Higher FH, potential for larger baby
else adjustmentFactor *= 0.97; // Lower FH, potential for smaller baby
}
// Adjust for previous birth weight (e.g., history of large baby)
if (prevWeightKg > 4.0) {
adjustmentFactor *= 1.05; // 5% increase if previous baby was large
}
// Adjust for presentation (minor adjustment, primarily impacts measurement accuracy not growth)
// This is more about measurement difficulty than growth itself. Breech might lead to slightly less reliable AC measurement.
if (presentation === 0) { // Breech
// Minor downward adjustment, reflecting potential measurement variance
// adjustmentFactor *= 0.98;
}
efwKg *= adjustmentFactor;
// Ensure minimum weight and cap at a reasonable maximum for the model
efwKg = Math.max(0.5, efwKg); // Minimum 0.5 kg
efwKg = Math.min(6.0, efwKg); // Maximum 6.0 kg for this illustrative model
// Convert kg to lbs and oz for display
var pounds = Math.floor(efwKg * 2.20462);
var ounces = Math.round((efwKg * 2.20462 – pounds) * 16);
// Handle cases where ounces round up to 16
if (ounces >= 16) {
pounds += Math.floor(ounces / 16);
ounces = ounces % 16;
}
var estimatedWeightStr = efwKg.toFixed(2) + " kg (" + pounds + " lbs " + ounces + " oz)";
document.getElementById('estimatedWeight').textContent = estimatedWeightStr;
document.getElementById('bpdValue').textContent = bpd.toFixed(2);
document.getElementById('flValue').textContent = fl.toFixed(2);
document.getElementById('acValue').textContent = ac.toFixed(2);
document.getElementById('efwComponent').textContent = efwKg.toFixed(2);
document.getElementById('result-container').style.display = 'block';
updateChart(ga, efwKg); // Update chart with the calculated weight
updateResultsSummary(ga, fh, maternalBmi, maternalAge, prevWeightKg, presentation, efwKg);
}
function updateResultsSummary(ga, fh, bmi, age, prevWeight, presentation, efwKg) {
var summaryDiv = document.getElementById('resultsSummary');
var summaryHtml = '
Key Assumptions & Factors:
';
summaryHtml += 'Gestational Age: ' + ga + ' weeks';
summaryHtml += 'Fundal Height: ' + fh + ' cm';
summaryHtml += 'Maternal BMI (Pre-preg): ' + bmi.toFixed(1) + ";
summaryHtml += 'Maternal Age: ' + age + ' years';
summaryHtml += 'Previous Birth Weight: ' + (prevWeight > 0 ? prevWeight.toFixed(2) + ' kg' : 'N/A') + ";
summaryHtml += 'Fetal Presentation: ' + (presentation === 1 ? 'Cephalic' : 'Breech') + ";
summaryHtml += 'Estimated Fetal Weight (EFW): ' + efwKg.toFixed(2) + ' kg';
summaryDiv.innerHTML = summaryHtml;
}
function updateChart(currentGA, currentEFW) {
var ctx = document.getElementById('efwChart').getContext('2d');
// Generate data points for a typical growth curve (simplified)
var growthCurveGA = [];
var growthCurveEFW_avg = []; // Average
var growthCurveEFW_high = []; // High end of normal
var growthCurveEFW_low = []; // Low end of normal
for (var ga = 20; ga <= 42; ga++) {
growthCurveGA.push(ga);
// Simplified EFW estimations for a typical growth curve (example values)
var avgWeight = 0.05 * ga + 0.3; // Very rough linear approximation
var lowWeight = avgWeight * 0.9;
var highWeight = avgWeight * 1.1;
growthCurveEFW_avg.push(avgWeight);
growthCurveEFW_low.push(lowWeight);
growthCurveEFW_high.push(highWeight);
}
// Ensure current EFW is within calculated range or add it if significantly outside
var foundCurrent = false;
for(var i=0; i 20 && currentGA <= 42) {
growthCurveGA.push(currentGA);
growthCurveEFW_avg.push(currentEFW);
growthCurveEFW_low.push(currentEFW * 0.9);
growthCurveEFW_high.push(currentEFW * 1.1);
// Sort the arrays to maintain order
var combined = [];
for (var i = 0; i 25 && maternalBmi = 30) adjustmentFactor *= 1.07;
if (defaultMaternalAge > 35) adjustmentFactor *= 1.02;
var fhDeviation = Math.abs(defaultFH – defaultGA);
if (fhDeviation > 4) { if (defaultFH > defaultGA) adjustmentFactor *= 1.04; else adjustmentFactor *= 0.97; }
if (defaultPrevWeightKg > 4.0) adjustmentFactor *= 1.05;
// if (defaultPresentation === 0) adjustmentFactor *= 0.98; // Uncomment if adjustment is desired
initialEfwKg *= adjustmentFactor;
initialEfwKg = Math.max(0.5, Math.min(6.0, initialEfwKg));
updateChart(defaultGA, initialEfwKg);
// Hide results initially until calculated
document.getElementById('result-container').style.display = 'none';
});
function resetCalculator() {
document.getElementById('gestationalAge').value = 39;
document.getElementById('fundalHeight').value = 35;
document.getElementById('maternalWeight').value = 65;
document.getElementById('maternalHeight').value = 165;
document.getElementById('maternalAge').value = 30;
document.getElementById('previousBirthWeight').value = 3.2;
document.getElementById('fetalPresentation').value = 1; // Cephalic
// Clear errors
document.getElementById('gestationalAgeError').textContent = ";
document.getElementById('fundalHeightError').textContent = ";
document.getElementById('maternalWeightError').textContent = ";
document.getElementById('maternalHeightError').textContent = ";
document.getElementById('maternalAgeError').textContent = ";
document.getElementById('previousBirthWeightError').textContent = ";
document.getElementById('estimatedWeight').textContent = '–';
document.getElementById('bpdValue').textContent = '–';
document.getElementById('flValue').textContent = '–';
document.getElementById('acValue').textContent = '–';
document.getElementById('efwComponent').textContent = '–';
document.getElementById('resultsSummary').innerHTML = ";
document.getElementById('result-container').style.display = 'none';
// Reset chart to default view (optional, could also recalculate with defaults)
var defaultGA = 39;
var defaultEFW = 3.1; // Approximate default EFW for GA 39
// Re-run the calculation with default values to update chart accurately
calculateCSectionWeight();
}
function copyResults() {
var estimatedWeight = document.getElementById('estimatedWeight').textContent;
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var flValue = document.getElementById('flValue').textContent;
var acValue = document.getElementById('acValue').textContent;
var efwComponent = document.getElementById('efwComponent').textContent;
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var resultsText = "C Section Estimated Birth Weight Results:\n\n";
resultsText += "Estimated Weight: " + estimatedWeight + "\n";
resultsText += "Biparietal Diameter (BPD): " + bpdValue + " cm\n";
resultsText += "Femur Length (FL): " + flValue + " cm\n";
resultsText += "Abdominal Circumference (AC): " + acValue + " cm\n";
resultsText += "EFW Formula Component: " + efwComponent + " kg\n\n";
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