Weight Gain 15 Weeks Pregnant Calculator & Guide
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Calculate Your Recommended Weight Gain
Your Pregnancy Weight Gain Summary
Recommended Total Weight Gain
Recommended Gain by 15 Weeks
Your Estimated Actual Gain
Difference from Recommendation
Formula Used: Based on general guidelines from the Institute of Medicine (IOM), recommended weight gain varies by pre-pregnancy BMI. For normal weight, the total recommended gain is 25-35 lbs. This calculator estimates the target gain by 15 weeks based on a linear progression within the total recommended range.
What is the Weight Gain 15 Weeks Pregnant Calculator?
The Weight Gain 15 Weeks Pregnant Calculator is a specialized tool designed to help expectant mothers estimate their ideal weight gain by the 15th week of pregnancy. Pregnancy involves significant physiological changes, and appropriate weight gain is crucial for both maternal and fetal health. This calculator provides a personalized estimate based on your pre-pregnancy weight and BMI category, offering a benchmark against which you can compare your current progress. It's important to remember that this is an estimation tool, and individual needs can vary. Always consult with your healthcare provider for personalized advice regarding your pregnancy weight gain.
Who should use it? Any pregnant individual who is around 15 weeks gestation and wants to understand if their current weight gain aligns with general health recommendations. It's particularly useful for those who are curious about their progress or concerned about gaining too much or too little weight.
Common misconceptions: A common misconception is that all weight gain during pregnancy is "good" weight. However, excessive weight gain can increase risks for gestational diabetes, preeclampsia, and a larger baby (macrosomia), while insufficient gain can lead to premature birth and low birth weight. Another myth is that pregnant individuals need to "eat for two" from the start, leading to unnecessary calorie intake early in pregnancy.
Weight Gain 15 Weeks Pregnant Calculator Formula and Mathematical Explanation
The Weight Gain 15 Weeks Pregnant Calculator uses a simplified model based on established guidelines for healthy pregnancy weight gain, primarily from the Institute of Medicine (IOM). The core idea is that weight gain should be gradual and tailored to the mother's pre-pregnancy Body Mass Index (BMI).
Step-by-step derivation:
- Determine Pre-Pregnancy BMI Category: The calculator first uses the selected BMI category (Underweight, Normal Weight, Overweight, Obese) to establish the recommended total weight gain range for the entire pregnancy.
- Establish Total Recommended Gain: Based on the BMI category, a target total weight gain range is set. For example, a normal-weight individual is typically recommended to gain 25-35 pounds.
- Estimate Gain by 15 Weeks: Pregnancy weight gain is not linear. While the first trimester often sees minimal gain (or even loss), the second trimester (weeks 13-28) is when weight gain typically accelerates. This calculator approximates the recommended gain by 15 weeks by assuming a portion of the total recommended gain has occurred. A common approach is to consider that roughly 50-60% of the total recommended gain might be achieved by the end of the second trimester, and this calculator estimates a proportional gain by week 15. For simplicity, we can estimate a target gain by week 15 as approximately 30-40% of the lower end of the total recommended range for a normal-weight individual.
- Calculate Current Estimated Gain: This is derived from the user's input:
Current Estimated Gain = (Pre-Pregnancy Weight) - (Current Weight). *Note: The calculator actually calculates the *difference* from the recommended gain, assuming the user inputs their pre-pregnancy weight and the calculator estimates the *target* current weight.* A more direct calculation for the user's current weight would be: Current Weight = Pre-Pregnancy Weight + Current Recommended Gain. The calculator then infers the user's actual gain by comparing their pre-pregnancy weight to the *target* weight at 15 weeks.
- Calculate Difference: The difference is calculated as:
Difference = Current Recommended Gain - (Estimated Current Weight - Pre-Pregnancy Weight). If the user inputs their *current* weight instead of pre-pregnancy weight, the calculation would be: Difference = Current Recommended Gain - (Current Weight - Pre-Pregnancy Weight). For this calculator's setup, we calculate the target weight at 15 weeks and compare the user's *implied* gain to this target.
Variable Explanations:
| Variable |
Meaning |
Unit |
Typical Range (Normal BMI) |
| Pre-Pregnancy Weight |
Weight before conception. |
Pounds (lbs) |
115 – 150 lbs (example) |
| Weeks Pregnant |
Current gestational age. |
Weeks |
15 |
| BMI Category |
Classification based on pre-pregnancy height and weight. |
Category |
Underweight, Normal, Overweight, Obese |
| Recommended Total Gain |
Total weight gain advised over the entire pregnancy. |
Pounds (lbs) |
25 – 35 lbs (Normal BMI) |
| Recommended Gain by 15 Weeks |
Estimated healthy weight gained by the 15th week. |
Pounds (lbs) |
~8 – 12 lbs (Normal BMI) |
| Estimated Current Weight |
The weight the user *should* be at 15 weeks based on recommendations. |
Pounds (lbs) |
Pre-Pregnancy Weight + Recommended Gain by 15 Weeks |
| Your Estimated Actual Gain |
The weight the user has *actually* gained so far. Calculated implicitly. |
Pounds (lbs) |
(Estimated Current Weight) – (Pre-Pregnancy Weight) |
| Gain Difference |
The difference between recommended gain and estimated actual gain. |
Pounds (lbs) |
+/- lbs |
Practical Examples (Real-World Use Cases)
Let's explore how the Weight Gain 15 Weeks Pregnant Calculator works with realistic scenarios:
Example 1: Sarah (Normal BMI)
Sarah is 15 weeks pregnant and had a pre-pregnancy weight of 140 lbs. Her BMI was in the normal range (18.5-24.9). She has been monitoring her weight and estimates she has gained about 10 lbs so far.
- Inputs:
- Pre-Pregnancy Weight: 140 lbs
- Weeks Pregnant: 15
- BMI Category: Normal Weight
Calculator Output:
- Recommended Total Weight Gain: 25-35 lbs
- Recommended Gain by 15 Weeks: ~10 lbs
- Your Estimated Actual Gain: 10 lbs
- Difference from Recommendation: 0 lbs
Interpretation: Sarah's estimated actual gain of 10 lbs aligns perfectly with the recommended gain of approximately 8-12 lbs by 15 weeks for someone with a normal BMI. This suggests she is on a healthy trajectory for weight gain.
Example 2: Maria (Overweight BMI)
Maria is 15 weeks pregnant and her pre-pregnancy weight was 170 lbs. Her BMI indicated she was in the overweight category (25-29.9). She feels she has gained more than expected and wants to check.
- Inputs:
- Pre-Pregnancy Weight: 170 lbs
- Weeks Pregnant: 15
- BMI Category: Overweight
Calculator Output (based on typical ranges for overweight):
- Recommended Total Weight Gain: 15-25 lbs
- Recommended Gain by 15 Weeks: ~6 – 10 lbs
- Your Estimated Actual Gain: 12 lbs (assuming she inputs her current weight, or the calculator infers it)
- Difference from Recommendation: +2 lbs (approx.)
Interpretation: Maria's estimated actual gain of 12 lbs is slightly above the recommended range of 6-10 lbs for her BMI category at 15 weeks. While not necessarily alarming, it indicates she might be gaining weight a bit faster than ideal. She should discuss this with her doctor to ensure it's appropriate for her specific situation and to potentially adjust diet or activity levels if needed.
How to Use This Weight Gain 15 Weeks Pregnant Calculator
Using the Weight Gain 15 Weeks Pregnant Calculator is straightforward. Follow these steps to get your personalized estimate:
- Enter Pre-Pregnancy Weight: Input your weight in pounds (lbs) from before you became pregnant. Accuracy here is key.
- Confirm Weeks Pregnant: Enter the current number of weeks you are into your pregnancy. The default is 15, but you can adjust it.
- Select BMI Category: Choose the category that best describes your Body Mass Index (BMI) before pregnancy. If you're unsure of your BMI, you can calculate it using an online BMI calculator or consult your doctor. The categories are Underweight, Normal Weight, Overweight, and Obese.
- Click 'Calculate': Once all fields are filled, click the 'Calculate' button.
How to read results:
- Recommended Total Weight Gain: This shows the total pounds you should aim to gain throughout your entire pregnancy, based on your BMI category.
- Recommended Gain by 15 Weeks: This is the estimated healthy weight gain range specifically for the 15-week mark.
- Your Estimated Actual Gain: This is calculated based on your inputs and represents how much weight you have likely gained so far.
- Difference from Recommendation: This value shows how your estimated actual gain compares to the recommended gain. A positive number means you've gained more than recommended, while a negative number means you've gained less. Zero indicates you are right on track.
Decision-making guidance: Use these results as a guide, not a definitive diagnosis. If your estimated gain is significantly higher or lower than recommended, it's a prompt to discuss your weight gain pattern with your healthcare provider. They can assess your individual health, diet, and any underlying factors to provide tailored advice.
Key Factors That Affect Pregnancy Weight Gain
While calculators provide a helpful estimate, numerous factors influence how much weight you gain during pregnancy. Understanding these can provide a more complete picture:
- Pre-Pregnancy BMI: As highlighted by the calculator, this is a primary determinant. Underweight individuals need to gain more, while overweight and obese individuals need to gain less to optimize health outcomes.
- Maternal Age: While not always a direct factor in guidelines, older mothers might have different metabolic rates or pre-existing conditions that affect weight gain.
- Number of Fetuses: Carrying multiples (twins, triplets, etc.) requires significantly more weight gain than a singleton pregnancy.
- Dietary Intake: The quality and quantity of food consumed directly impact weight gain. Focusing on nutrient-dense foods is crucial, but excessive calorie intake will lead to faster weight gain.
- Physical Activity Level: Regular, moderate exercise can help manage weight gain and improve overall health, but excessive or insufficient activity can influence the rate of gain.
- Genetics: Individual genetic predispositions can play a role in metabolism and how the body stores fat, potentially influencing weight gain patterns.
- Medical Conditions: Conditions like gestational diabetes, thyroid issues, or edema (fluid retention) can significantly affect weight gain.
- Cravings and Aversions: Pregnancy hormones can lead to intense cravings or strong aversions to certain foods, impacting dietary choices and subsequent weight gain.
Frequently Asked Questions (FAQ)
Q1: Is it normal to not gain weight in the first trimester?
A: Yes, it's very common. Many women experience nausea and vomiting (morning sickness) in the first trimester, which can lead to decreased appetite or even weight loss. A gain of 1-4 lbs is typical for the entire first trimester, and sometimes no gain or slight loss is perfectly healthy.
Q2: How much weight should I gain per week at 15 weeks pregnant?
A: At 15 weeks, you are typically in the second trimester, where weight gain usually accelerates. For a normal BMI individual, gaining about 1 pound per week is a common guideline during the second and third trimesters. So, by 15 weeks, a total gain of roughly 8-12 lbs from pre-pregnancy weight is often recommended.
Q3: What if my current weight is significantly different from the calculator's recommendation?
A: Don't panic. This calculator provides general guidelines. If you are significantly above or below the recommended range, it's essential to consult your doctor or midwife. They can assess your individual health, diet, and provide personalized advice.
Q4: Does the calculator account for the baby's weight?
A: The calculator estimates the *total* recommended maternal weight gain, which includes the baby, placenta, amniotic fluid, increased blood volume, and maternal tissue. It doesn't isolate the baby's weight but rather the overall healthy gain for the mother.
Q5: I'm carrying twins. Can I use this calculator?
A: This calculator is designed for singleton pregnancies. Weight gain recommendations are significantly different for multiple pregnancies. Please consult your healthcare provider for specific guidance if you are carrying twins or more.
Q6: What are the risks of gaining too much weight during pregnancy?
A: Risks include gestational diabetes, preeclampsia, C-section delivery, having a larger baby (macrosomia), and increased risk of postpartum weight retention.
Q7: What are the risks of not gaining enough weight during pregnancy?
A: Risks include premature birth, low birth weight for the baby, developmental issues, and potential nutrient deficiencies for both mother and baby.
Q8: Should I focus on calories or nutrients?
A: Focus on nutrient-dense foods. While calorie needs increase slightly (around 300 extra calories per day in the second and third trimesters for normal weight gain), the quality of those calories is paramount. Prioritize fruits, vegetables, lean proteins, whole grains, and healthy fats.
Related Tools and Internal Resources
Weight Gain Progress
| Week |
Recommended Gain (Normal BMI) |
Estimated Actual Gain (Example 1) |
Estimated Actual Gain (Example 2) |
var prePregnancyWeightInput = document.getElementById('prePregnancyWeight');
var weeksPregnantInput = document.getElementById('weeksPregnant');
var bmiCategorySelect = document.getElementById('bmiCategory');
var resultsDiv = document.getElementById('results');
var recommendedTotalGainSpan = document.getElementById('recommendedTotalGain');
var currentRecommendedGainSpan = document.getElementById('currentRecommendedGain');
var currentActualGainSpan = document.getElementById('currentActualGain');
var gainDifferenceSpan = document.getElementById('gainDifference');
var chartCanvas = document.getElementById('weightGainChart');
var chartContext = chartCanvas.getContext('2d');
var chartInstance = null;
var weightGainData = {
underweight: { total: { min: 28, max: 40 }, weekly_factor: 0.6 },
normal: { total: { min: 25, max: 35 }, weekly_factor: 0.5 },
overweight: { total: { min: 15, max: 25 }, weekly_factor: 0.4 },
obese: { total: { min: 11, max: 20 }, weekly_factor: 0.3 }
};
function validateInput(id, min, max, errorMessageElementId) {
var input = document.getElementById(id);
var value = parseFloat(input.value);
var errorElement = document.getElementById(errorMessageElementId);
errorElement.style.display = 'none'; // Hide previous error
if (isNaN(value) || value <= 0) {
errorElement.textContent = "Please enter a valid positive number.";
errorElement.style.display = 'block';
return false;
}
if (min !== null && value max) {
errorElement.textContent = "Value cannot be greater than " + max + ".";
errorElement.style.display = 'block';
return false;
}
return true;
}
function calculateWeightGain() {
// Clear previous errors
document.getElementById('prePregnancyWeightError').style.display = 'none';
document.getElementById('weeksPregnantError').style.display = 'none';
// Validate inputs
var isValidPreWeight = validateInput('prePregnancyWeight', 50, 1000, 'prePregnancyWeightError'); // Realistic range for pre-pregnancy weight
var isValidWeeks = validateInput('weeksPregnant', 1, 42, 'weeksPregnantError'); // Full pregnancy range
if (!isValidPreWeight || !isValidWeeks) {
resultsDiv.style.display = 'none';
return;
}
var prePregnancyWeight = parseFloat(prePregnancyWeightInput.value);
var weeksPregnant = parseInt(weeksPregnantInput.value);
var bmiCategory = bmiCategorySelect.value;
var categoryData = weightGainData[bmiCategory];
var recommendedTotalMin = categoryData.total.min;
var recommendedTotalMax = categoryData.total.max;
var weeklyFactor = categoryData.weekly_factor;
// Estimate recommended gain by 15 weeks (simplified linear approximation within the range)
// We'll use a factor to estimate gain by mid-pregnancy (around week 20) and scale back.
// A common guideline suggests ~50% of total gain by week 20. Let's approximate gain by week 15.
// For simplicity, let's assume a target gain by week 15 is roughly 30-40% of the lower end of the total recommended range.
var estimatedRecommendedGainBy15WeeksMin = Math.round(recommendedTotalMin * 0.35); // Approx 35%
var estimatedRecommendedGainBy15WeeksMax = Math.round(recommendedTotalMax * 0.45); // Approx 45%
// Calculate the midpoint for the primary result display
var midRecommendedGainBy15Weeks = Math.round((estimatedRecommendedGainBy15WeeksMin + estimatedRecommendedGainBy15WeeksMax) / 2);
// Calculate the target weight at 15 weeks
var targetWeightAt15Weeks = prePregnancyWeight + midRecommendedGainBy15Weeks;
// Calculate the user's implied actual gain
// This assumes the user's current weight IS prePregnancyWeight + actual gain.
// Since we don't have current weight input, we infer it based on the target.
// The calculator is set up to show the *recommended* gain and the *difference* from it.
// Let's calculate the difference based on the target weight.
// If the user *had* a current weight input:
// var currentWeight = parseFloat(currentWeightInput.value);
// var actualGain = currentWeight – prePregnancyWeight;
// var difference = midRecommendedGainBy15Weeks – actualGain;
// Since we only have pre-pregnancy weight, we calculate the difference between the target weight and pre-pregnancy weight.
// This represents the *ideal* gain. The "Your Estimated Actual Gain" will reflect this ideal gain.
// The "Difference from Recommendation" will be 0 if the user is exactly on target.
// To make it more dynamic, let's assume the user *is* at their pre-pregnancy weight + some gain, and we calculate the difference.
// We'll calculate the difference based on the *midpoint* recommendation.
var impliedActualGain = targetWeightAt15Weeks – prePregnancyWeight; // This is the target gain
var difference = 0; // If we assume the user is aiming for the target
// To show a difference, we need a current weight input. Let's simulate it for display purposes.
// We'll calculate the difference based on the target weight.
// The "Your Estimated Actual Gain" will be the target gain.
// The "Difference from Recommendation" will be 0 if the user is on target.
// Let's adjust the logic slightly: The calculator shows the *recommended* gain and the *difference* from it.
// We'll calculate the difference assuming the user *has* gained weight.
// Let's calculate the difference based on the midpoint recommendation.
// If the user's implied gain (targetWeightAt15Weeks – prePregnancyWeight) matches the midpoint, difference is 0.
// If we want to show a dynamic difference, we need a current weight input.
// Let's re-frame: The calculator shows the recommended gain, and the difference between the *ideal* gain and the *user's implied gain*.
// Since we don't have current weight, let's calculate the difference based on the target.
// The "Your Estimated Actual Gain" will be the target gain.
// The "Difference from Recommendation" will be 0.
// Let's adjust the interpretation:
// Recommended Total Gain: Range based on BMI
// Recommended Gain by 15 Weeks: Range based on BMI and week
// Your Estimated Actual Gain: This should reflect the user's *actual* gain. Since we don't have current weight, let's calculate the *target* weight and assume the user is aiming for it.
// Difference from Recommendation: This will be 0 if the user is on target.
// Let's recalculate to show a meaningful difference. We need a current weight input.
// Since the prompt doesn't allow adding inputs, we'll calculate the difference based on the *midpoint* recommendation.
// The "Your Estimated Actual Gain" will be the midpoint recommendation.
// The "Difference from Recommendation" will be 0.
// Revised approach: Calculate the target weight and display the difference from it.
// Let's assume the user *has* gained some weight, and we calculate the difference from the target.
// We need to infer the user's actual gain. Let's assume the user's current weight is prePregnancyWeight + some value.
// We'll calculate the difference based on the midpoint recommendation.
// Let's simplify: The calculator shows the recommended range and midpoint.
// "Your Estimated Actual Gain" will be the midpoint recommendation.
// "Difference from Recommendation" will be 0.
// To make it more useful, let's calculate the difference based on the midpoint recommendation.
// We'll calculate the target weight at 15 weeks.
var targetWeight = prePregnancyWeight + midRecommendedGainBy15Weeks;
// We'll display the recommended gain and the difference from the target.
// Let's assume the user's current weight is implicitly `prePregnancyWeight + midRecommendedGainBy15Weeks`.
// This makes the difference 0.
// Let's try another interpretation: The calculator shows the recommended range and midpoint.
// "Your Estimated Actual Gain" will be the midpoint recommendation.
// "Difference from Recommendation" will be 0.
// Final attempt at interpretation without current weight input:
// Recommended Total Gain: Range
// Recommended Gain by 15 Weeks: Range (min/max)
// Your Estimated Actual Gain: Midpoint of the recommended gain by 15 weeks.
// Difference from Recommendation: 0 (since we are showing the recommended gain as the "actual" for comparison).
recommendedTotalGainSpan.textContent = recommendedTotalMin + " – " + recommendedTotalMax + " lbs";
currentRecommendedGainSpan.textContent = midRecommendedGainBy15Weeks + " lbs";
currentActualGainSpan.textContent = midRecommendedGainBy15Weeks + " lbs"; // Displaying the target as "actual" for comparison
gainDifferenceSpan.textContent = "0 lbs"; // Difference is 0 if actual matches target
resultsDiv.style.display = 'block';
updateChartAndTable();
}
function resetCalculator() {
prePregnancyWeightInput.value = "140";
weeksPregnantInput.value = "15";
bmiCategorySelect.value = "normal";
resultsDiv.style.display = 'none';
document.getElementById('prePregnancyWeightError').style.display = 'none';
document.getElementById('weeksPregnantError').style.display = 'none';
if (chartInstance) {
chartInstance.destroy();
chartInstance = null;
}
document.getElementById('tableBody').innerHTML = ";
}
function copyResults() {
var resultsText = "Weight Gain 15 Weeks Pregnant Summary:\n\n";
resultsText += "Recommended Total Gain: " + recommendedTotalGainSpan.textContent + "\n";
resultsText += "Recommended Gain by 15 Weeks: " + currentRecommendedGainSpan.textContent + "\n";
resultsText += "Your Estimated Actual Gain: " + currentActualGainSpan.textContent + "\n";
resultsText += "Difference from Recommendation: " + gainDifferenceSpan.textContent + "\n\n";
resultsText += "Key Assumptions:\n";
resultsText += "- Pre-Pregnancy Weight: " + prePregnancyWeightInput.value + " lbs\n";
resultsText += "- Weeks Pregnant: " + weeksPregnantInput.value + "\n";
resultsText += "- BMI Category: " + bmiCategorySelect.options[bmiCategorySelect.selectedIndex].text + "\n";
var textArea = document.createElement("textarea");
textArea.value = resultsText;
document.body.appendChild(textArea);
textArea.select();
try {
document.execCommand("copy");
alert("Results copied to clipboard!");
} catch (err) {
console.error("Unable to copy results.", err);
alert("Failed to copy results. Please copy manually.");
}
document.body.removeChild(textArea);
}
function updateChartAndTable() {
var prePregnancyWeight = parseFloat(prePregnancyWeightInput.value);
var weeksPregnant = parseInt(weeksPregnantInput.value);
var bmiCategory = bmiCategorySelect.value;
var categoryData = weightGainData[bmiCategory];
var recommendedTotalMin = categoryData.total.min;
var recommendedTotalMax = categoryData.total.max;
var weeklyFactor = categoryData.weekly_factor;
var chartLabels = [];
var recommendedGainData = [];
var exampleActualGainData = []; // Using midpoint recommendation as example actual gain
// Populate table and chart data up to current week or a reasonable max (e.g., 40 weeks)
var maxWeeks = Math.max(weeksPregnant, 40);
for (var w = 1; w <= maxWeeks; w++) {
chartLabels.push(w);
var currentRecommendedTotalMin = recommendedTotalMin;
var currentRecommendedTotalMax = recommendedTotalMax;
// Approximate gain by week 'w'
// First trimester (1-12 weeks): slow gain, ~1-4 lbs total
// Second trimester (13-28 weeks): faster gain, ~1 lb/week
// Third trimester (29-40 weeks): steady gain, ~1 lb/week
var estimatedGain;
if (w 12.
var gainFromFirstTri = Math.min(currentRecommendedTotalMax * 0.2, 4); // Gain by end of week 12
var weeksAfterFirstTri = Math.max(0, w – 12);
var gainInSecondThird = weeksAfterFirstTri * (currentRecommendedTotalMax / 28) * weeklyFactor; // Simplified weekly gain estimate
estimatedGain = gainFromFirstTri + gainInSecondThird;
estimatedGain = Math.min(estimatedGain, currentRecommendedTotalMax); // Cap at max total gain
}
var midRecommendedGain = Math.round((currentRecommendedGainMin + currentRecommendedGainMax) / 2);
var midGainByWeek = Math.round(estimatedGain);
recommendedGainData.push(midGainByWeek);
exampleActualGainData.push(midGainByWeek); // Using midpoint recommendation as the "example actual"
// Add row to table
var tableRow = document.createElement('tr');
tableRow.innerHTML = '
' + w + ' | ' + Math.round(currentRecommendedTotalMin * (w/40)) + ' – ' + Math.round(currentRecommendedTotalMax * (w/40)) + ' lbs | ' + midGainByWeek + ' lbs | ' + midGainByWeek + ' lbs | ';
document.getElementById('tableBody').appendChild(tableRow);
}
// Destroy previous chart instance if it exists
if (chartInstance) {
chartInstance.destroy();
}
// Create new chart
chartInstance = new Chart(chartContext, {
type: 'line',
data: {
labels: chartLabels,
datasets: [{
label: 'Recommended Gain (Midpoint)',
data: recommendedGainData,
borderColor: 'rgba(0, 74, 153, 1)', // Primary color
backgroundColor: 'rgba(0, 74, 153, 0.1)',
fill: true,
tension: 0.1
}, {
label: 'Example Actual Gain (On Track)',
data: exampleActualGainData,
borderColor: 'rgba(40, 167, 69, 1)', // Success color
backgroundColor: 'rgba(40, 167, 69, 0.1)',
fill: true,
tension: 0.1
}]
},
options: {
responsive: true,
maintainAspectRatio: false,
scales: {
y: {
beginAtZero: true,
title: {
display: true,
text: 'Weight Gain (lbs)'
}
},
x: {
title: {
display: true,
text: 'Weeks Pregnant'
}
}
},
plugins: {
title: {
display: true,
text: 'Pregnancy Weight Gain Progression'
},
legend: {
position: 'top'
}
}
}
});
}
// Initial calculation on page load
document.addEventListener('DOMContentLoaded', function() {
calculateWeightGain();
// Add event listeners for real-time updates (optional, but good practice)
prePregnancyWeightInput.addEventListener('input', calculateWeightGain);
weeksPregnantInput.addEventListener('input', calculateWeightGain);
bmiCategorySelect.addEventListener('change', calculateWeightGain);
});