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Whether you are trying to avoid getting pregnant or are trying to conceive, keeping a fertility calendar can be quite helpful. With a fertility calendar you can calculate your most fertile days of the month and calculate your due date should you become pregnant. Fortunately today, there are a variety of fertility calendars on the market that can be quite useful.
What is the Fertility Window
Fertility means the ability to reproduce — conceive and bear children. What is the fertility window? You cannot get pregnant at any point in your menstrual cycle. There is actually just a small window of days when it is the best time to get pregnant, or the days to avoid getting pregnant. This is called the fertility window. With many women having irregular menstrual cycles, calculating their ovulation period and the fertile window is highly recommended. A prospective study shows that the fertility window is around 6 days long. This includes the ovulation day and the life of the sperm, which is about 5 days.
Ovulation happens at about 10-12 hours after the LH peak. The release of the monthly mature egg takes place, and hormones will play a key role during this time. These hormones include Follicle-Stimulating Hormone (FSH), estrogen, Luteinizing Hormone (LH), and progesterone. The dominant hormones during ovulation are dependent upon the levels of 17-beta-estradiol, which may lead to high levels of FSH and LH. Its high levels lead to the LH surge which increases the activity of the proteolytic enzymes that weaken the ovarian wall, at which time the mature follicle breaks, releasing an oocyte (egg). The steroid hormone, progesterone, prepares the endometrium for the uterine implantation of the fertilized egg and maintenance of pregnancy. You may consider using Ovulation Calendar and Pregnancy Wheel, it provides day-to-day information on fertility, ovulation and pregnancy milestones.
When trying to conceive, paying attention to, and understanding your menstrual cycle, is key as you begin to use the ovulation or fertile calendar. Take note that the length of each phase can vary from person to person, and can also change over time and with age. Read more here about the Menstrual Cycle Chart.
A woman’s menstrual cycle length can vary from 26 to 35 days. Let’s review the phases of the normal menstrual cycle.
1. Menstrual Phase
We call this the menstrual period which usually lasts for 3 to 8 days. It begins when the unfertilized egg in the previous cycle, along with the uterine lining, breaks down into blood, mucus, and uterus tissue, and exits through the vagina.
2. The Follicular Phase
This phase typically takes 10-14 days. and happens simultaneously with the menstrual phase. The follicle-stimulating hormone (FSH) prompts the ovaries to produce about 15 to 20 mature eggs, each encased in its own follicle. These follicles then produce estrogen and stimulate the uterine lining to thicken, thus providing the nutrients needed by the fertilized egg.
3. The Ovulation Phase
The moment the ovary releases a mature egg, the ovulation phase begins. There is an LH surge and the egg journeys from the ovary, down to the fallopian tube, then into the uterus. The egg meets its partner sperm and is fertilized. It if doesn’t, it will disintegrate after 24 hours. (Best time to start a progesterone cream like Cycle Balance Oil, PMS Balance Cream or Organic Fertile Balance)
4. The Luteal Phase
This is the last phase when implantation takes place. Progesterone is released and keeps the uterine wall thick for the fertilized egg to implant and develop into an embryo. Typically, the luteal phase lasts about two weeks. Note: If you have a short luteal phase consider Fertile Lady. Read more here about Luteal Phase Defect.
The fertility calendar method is intended to predict general trends based on when you begin to menstruate (bleeding) and when it ends. Tracking fertility using the calendar method will take a few months of observation in order to obtain a good picture. If your menstrual cycle is fairly regular, you can assume that you will begin to ovulate somewhere between the 12th and 16th day before you begin to bleed again.
At present, the classical calendar method of estimating the next ovulation date also records the user’s personal information. There are many mobile phone apps women can use to help them map their ovulation and menstrual cycles and facilitate successful conceptions or avoid them. Here are four simple steps as you begin to use the ovulation calendar:
- Chart the first day that bleeding begins as ‘Day One.’ For each subsequent month thereafter, you will do the same thing.
- Take note of how many days you bleed and how many days there are between each cycle.
- To determine the first day you are most likely to begin ovulation, pick the shortest cycle of the previous month’s records. Subtract 18 from the total number of days in the cycle. For instance, if your shortest cycle is 26 days long, you will subtract 18 from 26, which leaves 8 days. Then, begin with Day One of your current cycle and count ahead 10 – 14 days. This is the day that you will most likely begin to ovulate and be most fertile.
- To estimate the last fertile day of your present cycle, find the longest cycle in your record, then subtract 11 from the total number of days in that cycle. Count that number from your day 1 (the first day of bleeding) and mark that day with an X. Day 1 should be included when you count. The day marked X is your last fertile day.
It is helpful to note also that there are scientific data that suggest the insufficiency of the self-reported menstrual history and calendar-based methods of counting. Urinary tests and blood samples still prove essential to verify proper menstrual cycle events.
Ideally, when trying to conceive, the fertility calendar method is most helpful when used in combination with other predictive fertility strategies such as cervix positioning, saliva testing, BBT charting, and/or with fertility tester kits like Ovacue Fertility Monitor.