Chances of Getting Pregnant

Due to natural hormonal fluctuations driving menstruation, a woman's odds of getting pregnant greatly vary during the cycle. The following breakdown is based on a 28-day cycle, though healthy period patterns can last from 21 to 35 days. 

Chances of Pregnancy During Period

For most women with 28-day cycles, the odds of pregnancy while on a period are nil because their fertile window does not start until Day 9. However, those with shorter cycles might be entering their fertility days while still bleeding.

Chances of Pregnancy After Period and Before Ovulation

The odds of pregnancy increase with every day that passes after a period as a woman is approaching her fertile window. Having sex during the five days before ovulation is a woman's best chance to get pregnant. Those with short cycles might already be in their most fertile days right after a period and before ovulation.

Chances of Pregnancy during Ovulation

Ovulation, which lasts for 12 to 24 hours, is the only time during which the egg can be fertilized if the sperm is present by the fallopian tubes. As such, having sex on ovulation day guarantees very high chances of pregnancy.

Chances of Pregnancy After Ovulation and Before Period

The time of the lowest probability of pregnancy is after ovulation and until the next period. When the egg is not fertilized by the sperm during the 24-hour window, it will move to the uterus to be shed about two weeks later with menstrual bleeding.

Additional Information

For women with irregular periods or irregular ovulation, it is best to track their menstrual patterns with the help of ovulation tests, such as checking cervical mucus, as they help detect bodily clues that fertile days are approaching.

Women are generally conscious of an age-related natural fertility decline. Many, however, are not sure what exactly their odds of pregnancy are at various ages.

Chances of Pregnancy in the 20s

A woman in her 20s has the best chance to get pregnant, about 25% per cycle, as her ovarian reserve is abundant, and the majority of her eggs are chromosomally normal. As such, 96% of 20-year-olds conceive within a year of trying.

Chances of Pregnancy in the 30s

Turning 30 comes with the first reproductive challenges, although a woman's fertility rates continue high with about 86% of women in this age range conceiving within a year. However, fertility at 35 begins to declines at faster rates.

Chances of Pregnancy in the 40s

Chances of Pregnancy in the 50s

A woman's odds of pregnancy mainly depend on two factors: the type of birth control she is on and her diligence in following the schedule.

Failure rates of various contraceptive methods are often based on perfect use, which means a woman is using them as instructed every single time she has sex. In reality, most women practice what is referred to as typical use, which includes human error, such as forgetting the pill.

Despite common belief, women have the same chances of pregnancy after getting off birth control as those who have not used it.

However, what is more important is how quickly a woman's fertility returns after stopping birth control. For pregnancy to occur, a woman has to be ovulating. Because most birth control methods work by preventing ovulation, it might take time for normal ovulatory cycles to be fully restored.

It is important to remember that how long it takes to conceive depends on other factors as well. Consequently, it can take up to a year for a healthy couple to conceive.

How Does Breastfeeding Prevent Pregnancy?

Milk production in the breast is stimulated by the hormone prolactin following childbirth. Prolactin inhibits the release of other hormones that normally signal the ovaries to mature the eggs in the preparation for ovulation. Without those hormones, the ovulatory cycle cannot kick off. If a woman is not ovulating, conception cannot occur.

How Likely is it to Get Pregnant while Breastfeeding?

Generally, it is unlikely for a woman who is breastfeeding and whose period has not returned yet to get pregnant. In some cases, however, a woman might ovulate before the arrival of the first post-partum menses.

The likelihood of conceiving while breastfeeding is most commonly determined by the frequency and total amount of time the baby spends at the breasts per 24 hours. The two types of breastfeeding that are commonly used to delay the return of full fertility, exclusive and ecological breastfeeding, can range in their effectiveness varies from 1 to 6%.

As couples give conceiving a try, they often anxiously weigh their probability of pregnancy if they do not succeed right away, automatically suspecting infertility problems. In reality, making a baby is not as simple as it may seem, and it may take a healthy couple up to year of active trying to get pregnant.

For starters, learning to time intercourse with a woman's most fertile days takes several months of diligent tracking of menstrual patterns. Although progressing age does not affect men to a great extent, women's fertility is time-limited and rapidly declines after 35 as the ovaries run out of eggs, thus reducing the chances of pregnancy. When time is of the essence, possible fertility delays after stopping birth control might further complicate conception trials. Understanding all of the factors that naturally determine how likely is it to get pregnant is key to optimizing the baby-making process for ultimate success.