Estimate your fertile window and peak ovulation days to maximize your chances of conception.
Conception Calculator
Typically 21-35 days.
Usually 10-16 days, often around 14.
Estimated Fertile Window
—Days
—Estimated Ovulation Day
—Fertile Window Start
—Fertile Window End
How it Works
The conception calendar calculator estimates your fertile window and ovulation day based on your last menstrual period (LMP), average cycle length, and luteal phase length. Ovulation typically occurs about 14 days *before* the start of your next period (which is determined by the luteal phase length). Sperm can survive for up to 5 days in the female reproductive tract, and the egg is viable for about 12-24 hours. Therefore, the fertile window includes the days leading up to ovulation plus the day of ovulation itself.
Key Assumptions
Regular menstrual cycles.
Consistent luteal phase length.
Ovulation occurs approximately {Luteal Phase Length} days before the next period.
Sperm survival up to 5 days.
Egg viability up to 24 hours.
Fertility Window Visualization
Cycle Day Breakdown
Cycle Day
Description
Likelihood of Conception
Day 1 (LMP)
Start of Menstrual Period
Very Low
Fertile Window Start
Beginning of Fertile Window
Moderate to High
Estimated Ovulation
Peak Fertility
Highest
Fertile Window End
End of Fertile Window
Moderate
Post-Ovulation
After Fertile Window Closes
Very Low
What is a Conception Calendar Calculator?
A conception calendar calculator is a valuable online tool designed to help individuals and couples identify the most fertile days within a woman's menstrual cycle. By inputting specific details about a woman's menstrual cycle, the calculator estimates the timing of ovulation and the subsequent "fertile window" – the period during which intercourse is most likely to result in pregnancy. Understanding these fertile days is a cornerstone of trying to conceive (TTC), allowing couples to time their efforts strategically for the best possible outcome. This tool demystifies the biological process, making it more accessible and manageable for those on their family-building journey. It's crucial to remember that while this conception calendar calculator provides estimations, individual fertility can vary.
Who Should Use a Conception Calendar Calculator?
Anyone trying to conceive (TTC) can benefit from using a conception calendar calculator. This includes:
Couples who have been trying to get pregnant for a while and want to optimize their timing.
Individuals or couples who are new to TTC and want to understand their fertile periods better.
People with generally regular menstrual cycles who want to pinpoint ovulation more accurately.
Those looking to gain insights into their reproductive health and cycle patterns.
It's an essential tool for proactive family planning and understanding the nuances of the female reproductive cycle. While helpful, it's important to consult with a healthcare professional for personalized advice, especially if conception proves difficult or if there are underlying health concerns. This conception calendar calculator is a guide, not a definitive medical diagnosis.
Common Misconceptions
Misconception: Pregnancy happens only on the exact day of ovulation. Reality: The fertile window is several days long due to sperm's lifespan.
Misconception: All women have a 28-day cycle and ovulate on day 14. Reality: Cycle lengths vary significantly, and ovulation timing is relative to the *next* period, not just a fixed day.
Misconception: The calculator guarantees pregnancy. Reality: It increases the probability by helping time intercourse, but doesn't ensure conception due to many biological factors.
Misconception: You only need to track your period dates. Reality: Understanding cycle length and luteal phase is crucial for accurate calculation.
Conception Calendar Calculator Formula and Mathematical Explanation
The core of the conception calendar calculator relies on establishing the estimated day of ovulation, as this is the central event around which the fertile window is built. The calculation is primarily based on the understanding that ovulation occurs a predictable number of days *before* the onset of the next menstrual period.
Step-by-Step Derivation:
Determine Ovulation Day: Ovulation is estimated to occur {Luteal Phase Length} days before the start of the next expected period. Since the next period starts on Cycle Day {Cycle Length}, the estimated ovulation day is:
Ovulation Day = Cycle Length - Luteal Phase Length
Identify Fertile Window Start: Sperm can survive in the female reproductive tract for up to 5 days. Therefore, the fertile window begins approximately 5 days before the estimated ovulation day.
Fertile Window Start = Ovulation Day - 5 days
Identify Fertile Window End: The fertile window includes the ovulation day itself, as the egg is viable for about 12-24 hours post-ovulation.
Fertile Window End = Ovulation Day
Calculate Fertile Window Duration: The length of the fertile window is the duration from the start date to the end date.
Fertile Window Duration = Fertile Window End - Fertile Window Start + 1 day (adding 1 to include both start and end days)
Variable Explanations
To use this conception calendar calculator effectively, understanding the input variables is key:
Date of Last Menstrual Period (LMP): The first day of your most recent period. This serves as the anchor point (Day 1) for calculating subsequent cycle days.
Average Cycle Length: The total number of days from the first day of one period to the first day of the next. This is crucial for predicting when the next period is due.
Luteal Phase Length: The phase of the menstrual cycle that begins after ovulation and ends when menstruation begins. This phase is typically more consistent than the follicular phase and is used to pinpoint ovulation.
Variables Table
Variable
Meaning
Unit
Typical Range
Date of Last Menstrual Period (LMP)
First day of the last period
Calendar Date
N/A (specific date)
Average Cycle Length
Days from LMP to next LMP
Days
21 – 35 days (most common)
Luteal Phase Length
Days from Ovulation to next LMP
Days
10 – 16 days (most common: 14)
Ovulation Day
Estimated day of egg release
Cycle Day
Typically days 10-20 for a 28-day cycle, varies with cycle length.
Fertile Window Start
First day sperm can potentially fertilize an egg
Cycle Day
~5 days before ovulation
Fertile Window End
Last day an egg can potentially be fertilized
Cycle Day
Ovulation Day
Fertile Window Duration
Total number of days in the fertile window
Days
~6 days (5 days prior + ovulation day)
Practical Examples (Real-World Use Cases)
Example 1: Standard Cycle
Scenario: Sarah's last menstrual period (LMP) started on November 1st, 2023. She typically has a 28-day cycle and a consistent 14-day luteal phase.
Inputs:
LMP: 2023-11-01
Average Cycle Length: 28 days
Luteal Phase Length: 14 days
Calculations:
Estimated Ovulation Day: 28 – 14 = Day 14
Fertile Window Start: Day 14 – 5 = Day 9
Fertile Window End: Day 14
Fertile Window Duration: 14 – 9 + 1 = 6 days
Results:
Main Result (Fertile Window Duration): 6 days
Estimated Ovulation Day: November 14th, 2023 (Cycle Day 14)
Fertile Window: November 10th – November 14th, 2023
Interpretation: Sarah and her partner should aim to have intercourse between November 10th and November 14th to maximize their chances of conception. The highest likelihood is around November 14th.
Example 2: Longer Cycle
Scenario: Maria's LMP started on October 20th, 2023. She has a longer cycle of 35 days and a luteal phase of 15 days.
Inputs:
LMP: 2023-10-20
Average Cycle Length: 35 days
Luteal Phase Length: 15 days
Calculations:
Estimated Ovulation Day: 35 – 15 = Day 20
Fertile Window Start: Day 20 – 5 = Day 15
Fertile Window End: Day 20
Fertile Window Duration: 20 – 15 + 1 = 6 days
Results:
Main Result (Fertile Window Duration): 6 days
Estimated Ovulation Day: November 7th, 2023 (Cycle Day 20)
Fertile Window: November 3rd – November 7th, 2023
Interpretation: Maria's fertile window occurs later in her cycle compared to Sarah. She has a 6-day fertile window from November 3rd to November 7th, with peak fertility on November 7th. Timing intercourse within this window is key for conception.
How to Use This Conception Calendar Calculator
Using the conception calendar calculator is straightforward. Follow these steps to get your personalized fertile window estimate:
Record Your LMP: The first and most crucial step is to accurately note the start date (the first day) of your most recent menstrual period. Enter this date into the 'Date of Last Menstrual Period (LMP)' field.
Input Cycle Length: Determine your average menstrual cycle length. Count the number of days from the first day of your LMP to the first day of your *next* period. If your cycles vary, use a recent average. Enter this number in the 'Average Cycle Length' field.
Input Luteal Phase Length: While often around 14 days, this can vary. If you know your typical luteal phase length (the time between ovulation and your next period), enter it. Otherwise, the calculator defaults to 14 days, which is common. Enter this in the 'Luteal Phase Length' field.
View Results: Once the inputs are entered, the calculator will automatically update and display:
Estimated Fertile Window: The date range during which conception is most likely. This is highlighted as the primary result.
Estimated Ovulation Day: The most probable day you will ovulate.
Fertile Window Start & End Dates: The specific start and end dates of your fertile window.
Fertile Window Duration: The total number of days in your fertile window.
Understand the Chart and Table: The visualization and table provide a clear overview of your cycle, highlighting the fertile days relative to your cycle progression.
Copy Results: Use the 'Copy Results' button to save or share your calculated dates.
Reset: If you need to start over or input new data, use the 'Reset' button.
How to Read Results and Decision-Making Guidance
The primary result, Estimated Fertile Window Duration, tells you the number of days in your most fertile period. The accompanying start and end dates are what you should focus on. Aim to have intercourse regularly (every 1-2 days) during this window, especially in the 2-3 days leading up to and including your estimated ovulation day. Consistent intercourse during the fertile window significantly increases the chances of conception. If conception doesn't occur within a few cycles of using the calculator, consider consulting with a healthcare provider to discuss potential fertility factors.
Key Factors That Affect Conception Calendar Results
While the conception calendar calculator provides valuable estimates, several factors can influence actual fertility and the accuracy of the predictions:
Cycle Variability: The calculator assumes regular cycles. Stress, illness, travel, weight changes, hormonal fluctuations (like PCOS), and certain medications can cause irregular ovulation or alter cycle length, making predictions less precise.
Luteal Phase Inconsistency: While often stable, the luteal phase can sometimes vary. If your luteal phase is shorter than 10-11 days, it might indicate a condition like Luteal Phase Defect (LPD), which could impact implantation and requires medical attention.
Sperm Health and Lifespan: Sperm quality (motility, morphology) and viability can vary. While we assume up to 5 days of survival, suboptimal sperm health might reduce this window. Factors like diet, lifestyle, and medical conditions affect sperm health.
Egg Quality and Viability: Egg quality naturally declines with age. While the egg is viable for 12-24 hours post-ovulation, older eggs may be less likely to fertilize or develop properly, even if conception occurs.
Timing of Intercourse: Even within the fertile window, the frequency and timing of intercourse play a role. Having intercourse too early in the fertile window or less frequently than recommended can decrease chances. The calculator helps identify the window; strategic timing within it is key.
Underlying Medical Conditions: Conditions such as endometriosis, thyroid disorders, polycystic ovary syndrome (PCOS), fibroids, and sexually transmitted infections can affect fertility independently of the menstrual cycle timing.
Age: Female fertility naturally declines with age, particularly after 35. This affects egg quantity and quality, regardless of cycle timing.
Lifestyle Factors: Smoking, excessive alcohol consumption, high caffeine intake, poor nutrition, and being significantly underweight or overweight can negatively impact fertility for both partners.
Frequently Asked Questions (FAQ)
How accurate is a conception calendar calculator?
It's an estimation tool. Accuracy depends heavily on the regularity of your cycles and the accuracy of your inputs. For women with very regular cycles, it can be quite accurate in identifying the fertile window. However, it doesn't account for all biological variations.
What if my cycle length varies?
If your cycle length varies significantly, using an average might not be precise enough. Consider tracking your cycle over several months to get a better average or use ovulation predictor kits (OPKs) or basal body temperature (BBT) charting for more precise ovulation tracking. This conception calendar calculator is best suited for those with predictable cycles.
Can I get pregnant before or after my calculated fertile window?
Pregnancy is highly unlikely outside the calculated fertile window (approximately 5 days before ovulation through ovulation day). However, variations in sperm survival or egg viability, or slight inaccuracies in ovulation prediction, can mean the window is slightly wider or shifts slightly.
How often should we have intercourse during the fertile window?
For the best chances, aim for intercourse every 1-2 days within the fertile window, particularly during the 2-3 days leading up to and including the estimated ovulation day. This ensures sperm are available when the egg is released.
Does the calculator predict the baby's gender?
No, a conception calendar calculator has no ability to predict or influence the baby's gender. Gender is determined by the sperm (X or Y chromosome) at the moment of fertilization.
What if I'm on hormonal birth control?
Hormonal birth control typically prevents ovulation. If you are on birth control, this calculator is not applicable, as it relies on natural cycle tracking. You should wait to use this tool until after you have stopped birth control and your natural cycles have resumed.
Can this calculator be used for natural family planning (avoiding pregnancy)?
While the fertile window is identified, this calculator is primarily designed for those *trying* to conceive. Using it for contraception is highly unreliable due to the variability of ovulation and sperm lifespan. Natural family planning requires more rigorous methods and tracking.
When should I see a doctor if I'm trying to conceive?
It's generally recommended to consult a healthcare provider if you haven't conceived after one year of regular, unprotected intercourse (or after six months if you are over 35). A doctor can assess your fertility and discuss potential treatments or further investigations. Consulting before trying is also beneficial for preconception health advice.
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function validateAndCalculate(inputId, min, max) {
var errorElementId = inputId + 'Error';
var isValid = validateInput(inputId, min, max, errorElementId);
if (isValid) {
calculateConception();
}
}
function calculateConception() {
var lmpInput = getElement("lastMenstrualPeriod");
var cycleLength = getInputValue("cycleLength");
var lutealPhaseLength = getInputValue("lutealPhaseLength");
var lmpErrorElement = getElement("lastMenstrualPeriodError");
var cycleLengthErrorElement = getElement("cycleLengthError");
var lutealPhaseLengthErrorElement = getElement("lutealPhaseLengthError");
// Reset errors
clearError("lastMenstrualPeriodError");
clearError("cycleLengthError");
clearError("lutealPhaseLengthError");
var isValid = true;
// Validate LMP
if (!lmpInput || !lmpInput.value) {
displayError("lastMenstrualPeriodError", "Please enter the date of your last menstrual period.");
isValid = false;
}
// Validate Cycle Length
if (!validateInput("cycleLength", 1, 90, "cycleLengthError")) {
isValid = false;
}
// Validate Luteal Phase Length
if (!validateInput("lutealPhaseLength", 7, 20, "lutealPhaseLengthError")) {
isValid = false;
}
if (!isValid) {
// Clear results if any input is invalid
getElement("mainResult").innerText = "–";
getElement("ovulationDay").innerText = "–";
getElement("fertileWindowStart").innerText = "–";
getElement("fertileWindowEnd").innerText = "–";
updateChart([], []);
return;
}
var lmpDate = new Date(lmpInput.value);
// Adjust for timezone offset to ensure the date is treated as the start of the day
lmpDate.setHours(12, 0, 0, 0);
var ovulationDayOffset = cycleLength – lutealPhaseLength;
var fertileWindowStartOffset = ovulationDayOffset – 5;
var fertileWindowEndOffset = ovulationDayOffset; // Ovulation day is the end of the fertile window
// Calculate dates
var ovulationDate = new Date(lmpDate);
ovulationDate.setDate(lmpDate.getDate() + ovulationDayOffset -1); // -1 because LMP is Day 1
var fertileWindowStartDate = new Date(lmpDate);
fertileWindowStartDate.setDate(lmpDate.getDate() + fertileWindowStartOffset -1);
var fertileWindowEndDate = new Date(lmpDate);
fertileWindowEndDate.setDate(lmpDate.getDate() + fertileWindowEndOffset -1);
// Calculate results
var fertileWindowDuration = fertileWindowEndOffset – fertileWindowStartOffset + 1;
// Update display
getElement("mainResult").innerText = fertileWindowDuration + " days";
getElement("ovulationDay").innerText = formatDate(ovulationDate);
getElement("fertileWindowStart").innerText = formatDate(fertileWindowStartDate);
getElement("fertileWindowEnd").innerText = formatDate(fertileWindowEndDate);
// Update table
updateCycleTable(lmpDate, cycleLength, lutealPhaseLength, ovulationDayOffset, fertileWindowStartOffset, fertileWindowEndOffset);
// Update chart
var chartLabels = [];
var chartData = [];
var chartDataSperm = []; // Data for sperm survival
for (var i = 0; i = fertileWindowStartOffset && cycleDay fertileWindowStartOffset && cycleDay = fertileWindowStartOffset && cycleDay <= fertileWindowEndOffset +1) { // Fertile window starts 5 days before ovulation and ends day after ovulation
spermDataPoint = 1;
}
chartDataSperm.push(spermDataPoint);
}
updateChart(chartLabels, chartData, chartDataSperm, fertileWindowStartOffset, ovulationDayOffset, fertileWindowEndOffset);
// Update dynamic values in the formula explanation
var lutealPhaseSpan = document.querySelectorAll('.formula-explanation ul li')[1]; // Adjust index as needed
if (lutealPhaseSpan) {
lutealPhaseSpan.innerHTML = `Ovulation typically occurs about ${lutealPhaseLength} days *before* the start of your next period (which is determined by the luteal phase length).`;
}
var cycleLengthSpan = document.querySelectorAll('.formula-explanation ul li')[0]; // Adjust index as needed
if (cycleLengthSpan) {
cycleLengthSpan.innerHTML = `The fertile window includes the days leading up to ovulation plus the day of ovulation itself.`;
}
}
function updateCycleTable(lmpDate, cycleLength, lutealPhaseLength, ovulationDayOffset, fertileWindowStartOffset, fertileWindowEndOffset) {
var tbody = getElement("cycleTableBody");
tbody.innerHTML = ''; // Clear existing rows
var currentCycleDay = 1;
// Row 1: LMP Day
var dateLMP = new Date(lmpDate);
tbody.innerHTML += `
Day 1 (LMP)
Start of Menstrual Period
Very Low
`;
// Rows for days before fertile window (if any)
for (var i = 1; i < fertileWindowStartOffset – 1; i++) {
var date = new Date(lmpDate);
date.setDate(lmpDate.getDate() + i);
tbody.innerHTML += `
Day ${i+1}
Pre-Ovulation Phase
Low
`;
}
// Rows for Fertile Window Start
var dateFWS = new Date(lmpDate);
dateFWS.setDate(lmpDate.getDate() + fertileWindowStartOffset – 1);
tbody.innerHTML += `
Day ${fertileWindowStartOffset} (FW Start)
Beginning of Fertile Window
Moderate to High
`;
// Rows for days between FW start and Ovulation
for (var i = fertileWindowStartOffset; i < ovulationDayOffset; i++) {
var date = new Date(lmpDate);
date.setDate(lmpDate.getDate() + i);
tbody.innerHTML += `
Day ${i+1}
Approaching Ovulation
High
`;
}
// Row for Ovulation Day
var dateOvulation = new Date(lmpDate);
dateOvulation.setDate(lmpDate.getDate() + ovulationDayOffset – 1);
tbody.innerHTML += `
Day ${ovulationDayOffset} (Ovulation)
Peak Fertility
Highest
`;
// Rows for Fertile Window End
var dateFWE = new Date(lmpDate);
dateFWE.setDate(lmpDate.getDate() + fertileWindowEndOffset – 1);
tbody.innerHTML += `
Day ${fertileWindowEndOffset} (FW End)
End of Fertile Window
Moderate
`;
// Rows for post-ovulation
for (var i = fertileWindowEndOffset + 1; i <= cycleLength; i++) {
var date = new Date(lmpDate);
date.setDate(lmpDate.getDate() + i – 1);
var description = "Post-Ovulation Phase";
if (i === cycleLength) {
description = "Approaching Next Period";
}
tbody.innerHTML += `
Day ${i}
${description}
Very Low
`;
}
}
function formatDate(date) {
if (!date || isNaN(date.getTime())) return "–";
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return date.toLocaleDateString(undefined, options);
}
function copyResults() {
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var ovulationDay = getElement("ovulationDay").innerText;
var fertileWindowStart = getElement("fertileWindowStart").innerText;
var fertileWindowEnd = getElement("fertileWindowEnd").innerText;
var cycleLength = getInputValue("cycleLength");
var lutealPhaseLength = getInputValue("lutealPhaseLength");
var assumptionsText = "Assumptions:\n";
assumptionsText += "- Regular menstrual cycles.\n";
assumptionsText += "- Consistent luteal phase length.\n";
assumptionsText += "- Ovulation occurs approximately " + lutealPhaseLength + " days before the next period.\n";
assumptionsText += "- Sperm survival up to 5 days.\n";
assumptionsText += "- Egg viability up to 24 hours.\n";
var resultsText = "Conception Calendar Results:\n";
resultsText += "—————————–\n";
resultsText += "Estimated Fertile Window Duration: " + mainResult + "\n";
resultsText += "Estimated Ovulation Day: " + ovulationDay + "\n";
resultsText += "Fertile Window Start: " + fertileWindowStart + "\n";
resultsText += "Fertile Window End: " + fertileWindowEnd + "\n\n";
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function resetCalculator() {
setInputValue("lastMenstrualPeriod", ""); // Clear the date
setInputValue("cycleLength", 28);
setInputValue("lutealPhaseLength", 14);
// Clear errors
clearError("lastMenstrualPeriodError");
clearError("cycleLengthError");
clearError("lutealPhaseLengthError");
// Reset results
getElement("mainResult").innerText = "–";
getElement("ovulationDay").innerText = "–";
getElement("fertileWindowStart").innerText = "–";
getElement("fertileWindowEnd").innerText = "–";
getElement("cycleTableBody").innerHTML = `
Day 1 (LMP)
Start of Menstrual Period
Very Low
Fertile Window Start
Beginning of Fertile Window
Moderate to High
Estimated Ovulation
Peak Fertility
Highest
Fertile Window End
End of Fertile Window
Moderate
Post-Ovulation
After Fertile Window Closes
Very Low
`;
updateChart([], []); // Clear chart
}
function updateChart(labels, data, dataSperm, fwsDay, ovulationDay, fweDay) {
var ctx = getElement('fertilityChart').getContext('2d');
// Destroy previous chart instance if it exists
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}
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}
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labels: labels,
datasets: [
{
label: 'Fertility Level',
data: data,
backgroundColor: data.map(val => {
if (val === 3) return 'rgba(40, 167, 69, 0.8)'; // Green for Peak
if (val === 2) return 'rgba(0, 74, 153, 0.6)'; // Blue for Fertile
if (val === 1) return 'rgba(255, 193, 7, 0.6)'; // Yellow for Sperm Viable
return 'rgba(200, 200, 200, 0.3)'; // Light gray for low
}),
borderColor: data.map(val => {
if (val === 3) return 'rgba(40, 167, 69, 1)';
if (val === 2) return 'rgba(0, 74, 153, 1)';
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return 'rgba(200, 200, 200, 0.5)';
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borderWidth: 1,
fill: false,
tension: 0.1,
pointRadius: data.map(val => val > 0 ? 5 : 0) // Show points only for fertile/viable days
},
// Add a second series for Sperm Viability Check if needed, or use colors as above
{
label: 'Sperm Survival Window',
data: dataSperm,
backgroundColor: 'rgba(255, 193, 7, 0.4)', // Semi-transparent yellow for sperm
borderColor: 'rgba(255, 193, 7, 0.8)',
borderWidth: 1,
fill: true, // Fill the area under the line
tension: 0.1,
pointRadius: 0, // No points needed for this line itself
stepped: true // Optional: makes it look more like a window
}
]
};
var chartOptions = {
responsive: true,
maintainAspectRatio: false,
scales: {
y: {
beginAtZero: true,
ticks: {
// Custom tick display for clarity
callback: function(value, index, values) {
if (value === 3) return 'Peak Fertility';
if (value === 2) return 'Fertile';
if (value === 1) return 'Sperm Viable';
return "; // No label for 0 or intermediate values
}
},
title: {
display: true,
text: 'Likelihood of Conception'
}
},
x: {
title: {
display: true,
text: 'Cycle Day'
}
}
},
plugins: {
tooltip: {
callbacks: {
label: function(context) {
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}
if (label === 'Sperm Survival Window') {
// This dataset is for visual representation; tooltip might be less useful here directly
return null; // Hide tooltip for this dataset
}
return null; // Hide tooltip
}
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},
legend: {
position: 'top',
labels: {
filter: function(legendItem, chartData) {
// Filter legend items if necessary, e.g., hide the stepped line if it's confusing
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}
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}
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elements: {
line: {
borderColor: 'rgba(0, 74, 153, 0.7)', // Default line color
borderWidth: 2
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bar: {
borderWidth: 1
}
}
};
// Create new chart
chartInstance = new Chart(ctx, {
type: 'bar', // Using bar for distinct days, line for trends if preferred
data: chartData,
options: chartOptions
});
}
// Initial calculation on load
document.addEventListener('DOMContentLoaded', function() {
// Set initial values or trigger calculation if defaults are set
var lmpInput = getElement("lastMenstrualPeriod");
if (!lmpInput.value) {
// Optionally set a default LMP to the current date minus ~14 days for a starting point
var today = new Date();
today.setDate(today.getDate() – 14); // Assume today is mid-cycle
setDateValue("lastMenstrualPeriod", today);
}
calculateConception();
// Add event listener for FAQ toggling
var faqQuestions = document.querySelectorAll('.faq-question');
faqQuestions.forEach(function(question) {
question.addEventListener('click', function() {
var answer = this.nextElementSibling;
if (answer.style.display === 'block') {
answer.style.display = 'none';
} else {
answer.style.display = 'block';
}
});
});
});