Ovulation and Pregnancy Calculator
Whether pregnancy is desired or not, it is important to understand when and how ovulation occurs. An ovulation calculator can help. Here is how…
What is Ovulation?
Ovulation is a time during a woman’s menstrual cycle when she is most fertile. It occurs when a mature ovarian follicle releases an egg. The egg travels through the fallopian tubes. If sperm is present due to sexual intercourse, the egg can become fertilized.
The elevation or decline of female hormones activates certain ovulation phases during a menstrual cycle. There are three phases to this process:
- Follicular Phase (Periovulatory)
- Ovulation Phase (Ovulatory) This phase typically lasts between 24 to 48 hours. Because a woman’s menstrual cycle lasts between 28 and 32 days on average, ovulation generally occurs between day 10 and day 19.
- Luteal Phase (Postovulatory) A luteinizing hormone (LH) is secreted. If the egg is a fertilized egg, implantation occurs. If the egg is unfertilized, it will stop producing hormones. The uterus lining sheds and menstruation begins.
An average cycle is from 28 to 32 days. The length of days varies for some women and it is important to note this if the timing of fertility is important to you. A typical 28-day cycle is as follows:
Day 1 – Menstruation begins on this day.
Days 2 to 14 – The Follicular Phase (The ovary follicles become active; cervical mucus thins.)
Day 14 – Ovulation occurs; estrogen level rise and initiate the LH surge. The follicle of the ovaries releases an egg.
Days 15 to 22 – The Luteal Phase
Days 23 to 24 – If an egg is fertilized, it’s implanted in the uterus. Hormones are produced and able to be detected by a pregnancy test.
Days 25 to 28 – Hormones levels decrease if pregnancy did not occur. The lining in the uterus sheds, repeating the menstruation cycle.
Ovulation Calculator and Calendar
An ovulation calculator is not like those you use in school. It doesn’t have a keypad, but it does use calculations. In fact, ovulation is determined by counting 14 days backward from the last day of your period.
For example, if you have a 28-day cycle, subtract 14. You are pregnant on Day 14. If you have a 30-day cycle, you are fertile on Day 16.
Many women opt to use a visual aid in conjunction with an ovulation calculator. A year-at-a-glance style is preferable. Mark the first and last day of menstruation. You may want to figure out the Luteal Phase – the day following ovulation to the end of the menstruation cycle. Do this consistently each month and you will determine your cycle length.
Physical Signs of Ovulation
- The breasts become tender, and the abdominal region bloats.
- Slight vaginal spotting may occur.
- The amount of cervical mucus increases thickens and becomes stretchy due to higher estrogen levels. It may resemble egg whites.
- A woman’s body temperature will increase to 0.4 to 1.0 degrees. This is because progesterone is produced when an egg is released. Typically she is most fertile in the two or three days before this temperature hike.
- Some women feel a slight ache in their mid-section. It is called “Mittelschmerz” and means “middle pain” in German. This discomfort could last for a few minutes or a few hours.
- If a woman wants a more definite way to determine whether or not she’s ovulating, an ovulation predictor kit can be purchased. The kit uses urine to test the levels of luteinizing hormone (LH) before ovulation.
If a woman has become pregnant, she can use a pregnancy calculator to determine how far along she is. Pregnancy typically lasts 270 days from conception. That’s 40 weeks from the 1st day of the last menstrual cycle.
Many women use a pregnancy calculator that is in the shape of a wheel. This shows them, at quick glance, the day of delivery. There are also many computer programs that offer such a device. While a pregnancy calculator is helpful, doctors typically rely on ultrasounds for a more accurate calculation.