First Trimester (Weeks 1-13)
Second Trimester (Weeks 14-27)
Third Trimester (Weeks 28-40)
Sedentary (little to no exercise)
Lightly active (light exercise/sports 1-3 days/week)
Moderately active (moderate exercise/sports 3-5 days/week)
Very active (hard exercise/sports 6-7 days/week)
Extra active (very hard exercise/sports & physical job)
Enter your details to see your recommended calorie and nutrient intake.
Understanding Pregnancy Nutrition Needs
Proper nutrition during pregnancy is crucial for both the mother's health and the healthy development of the baby.
The recommended calorie intake, as well as specific nutrient needs, change throughout the trimesters. This calculator
provides an estimated guideline based on your individual characteristics and pregnancy stage.
How the Calculator Works:
This calculator estimates your basal metabolic rate (BMR) using the Mifflin-St Jeor equation, which is a common
formula for calculating energy expenditure. It then adjusts this BMR based on your activity level to determine
your total daily energy expenditure (TDEE) without pregnancy. Finally, it adds the recommended caloric surplus for
each trimester.
BMR Calculation (Mifflin-St Jeor for women):
BMR = (10 * weight in kg) + (6.25 * height in cm) – (5 * age in years) – 161
Note: Age is not included as an input to simplify the calculator, so a standard BMR estimation is used.
Activity Multipliers:
Sedentary: 1.2
Lightly active: 1.375
Moderately active: 1.55
Very active: 1.725
Extra active: 1.9
TDEE (Total Daily Energy Expenditure) = BMR * Activity Multiplier
Pregnancy Calorie Adjustment:
First Trimester: TDEE + 0 (No significant increase recommended)
Second Trimester: TDEE + 340 calories
Third Trimester: TDEE + 450 calories
Key Nutrients for Pregnancy:
Beyond calories, several nutrients are vital:
Folate (Folic Acid): Crucial for preventing neural tube defects. Found in leafy greens, fortified cereals, and beans.
Iron: Supports increased blood volume and oxygen transport. Good sources include red meat, poultry, fish, and legumes.
Calcium: Essential for baby's bone development and maintaining mother's bone density. Dairy products, leafy greens, and fortified foods are good sources.
Vitamin D: Aids calcium absorption. Found in fatty fish, fortified milk, and sunlight exposure.
Protein: Building blocks for baby's tissues and organs. Lean meats, poultry, fish, eggs, dairy, legumes, and nuts are excellent sources.
Omega-3 Fatty Acids (DHA): Important for baby's brain and eye development. Fatty fish like salmon is a primary source.
It's always recommended to consult with a healthcare provider or a registered dietitian for personalized
nutritional advice throughout your pregnancy. This calculator is a general guide and does not replace professional medical advice.
function calculateNutrition() {
var trimester = parseInt(document.getElementById("trimester").value);
var prePregnancyWeightKg = parseFloat(document.getElementById("prePregnancyWeightKg").value);
var currentWeightKg = parseFloat(document.getElementById("currentWeightKg").value);
var heightCm = parseFloat(document.getElementById("heightCm").value);
var activityLevel = document.getElementById("activityLevel").value;
var resultDiv = document.getElementById("result");
resultDiv.innerHTML = "; // Clear previous results
if (isNaN(prePregnancyWeightKg) || isNaN(currentWeightKg) || isNaN(heightCm) || heightCm <= 0) {
resultDiv.innerHTML = 'Please enter valid numbers for weight and height.';
return;
}
// Estimate BMR using Mifflin-St Jeor (simplified, as age is not input)
// For women: BMR = (10 * weight in kg) + (6.25 * height in cm) – (5 * age) – 161
// Since age is not an input, we'll use a simplified approach or assume a baseline age if needed for a more precise BMR,
// but for this calculator's purpose, we'll calculate TDEE without age for simplicity and focus on pregnancy adjustments.
// A direct calculation of TDEE using current weight and activity level is a common approach for general guidance.
// Let's use current weight for BMR calculation as it's more reflective of the body's current needs.
var bmr = (10 * currentWeightKg) + (6.25 * heightCm) – 161; // Simplified BMR without age
var activityMultiplier;
switch (activityLevel) {
case "sedentary":
activityMultiplier = 1.2;
break;
case "light":
activityMultiplier = 1.375;
break;
case "moderate":
activityMultiplier = 1.55;
break;
case "very":
activityMultiplier = 1.725;
break;
case "extra":
activityMultiplier = 1.9;
break;
default:
activityMultiplier = 1.2; // Default to sedentary
}
var tdee = bmr * activityMultiplier;
var calorieSurplus = 0;
if (trimester === 2) {
calorieSurplus = 340;
} else if (trimester === 3) {
calorieSurplus = 450;
}
// First trimester has no significant calorie surplus recommended in general guidelines.
var totalCalories = tdee + calorieSurplus;
// Basic nutrient estimations (these are very rough and for illustrative purposes)
// Protein: 1.1g per kg of pre-pregnancy weight during pregnancy is often recommended.
var recommendedProteinGrams = prePregnancyWeightKg * 1.1;
// Iron: ~27 mg per day for most pregnant women
var recommendedIronMg = 27;
// Calcium: ~1000-1300 mg per day
var recommendedCalciumMg = 1200;
var resultHtml = 'Estimated Daily Needs:';
resultHtml += 'Calories: ' + Math.round(totalCalories) + ' kcal';
resultHtml += 'Protein: ~' + Math.round(recommendedProteinGrams) + ' g';
resultHtml += 'Iron: ~' + recommendedIronMg + ' mg';
resultHtml += 'Calcium: ~' + recommendedCalciumMg + ' mg';
resultHtml += 'These are general estimates. Consult your healthcare provider for personalized advice.';
resultDiv.innerHTML = resultHtml;
}