Understanding Your Odds of Pregnancy by Age (+ Chart)
From your doctor asking if you’re thinking about getting pregnant soon to nosy relatives asking when you’re going to “settle down,” you may have felt your biological clock counting down already. With all the pressure placed on women to have a baby by a certain age, it can be easy to feel like your fertility is a ticking time bomb.
Thankfully, age does not necessarily limit your fertility as much as you may think. More and more women are choosing to wait until their 30s and 40s to have a child for reasons like pursuing career goals, traveling the world, or finding the right partner.
Still, that does not mean that your fertility is an unlimited reserve. While it’s becoming more common — and, thanks to modern medical technology, safer — to have children at an older age, your fertility still changes significantly as you get older. Here’s what you need to know to understand your odds of pregnancy by age.
Understanding Your Odds of Pregnancy by Age
Our eggs age with us. When eggs age, they are more likely to become chromosomally abnormal. This means there are small mistakes in the DNA of the egg. Abnormal DNA can cause cells to function improperly — and, in the case of an egg, may mean that they are unable to become fertilized or mature into a healthy fetus.
In your early 20s, 90% of your eggs are genetically normal. By your mid-40s, however, fewer than 20% of your eggs remain healthy. Knowing this information and how it affects your chances of pregnancy at different ages is important, but knowing what to do with it is even more important!
Getting Pregnant in Your 20s
Many sources, including the American Society for Reproductive Medicine, still believe that a woman’s best years to have a baby are her 20s. A healthy couple under 30 has approximately a 95% chance of getting pregnant after a year of having unprotected sex. Unless you have a health condition impacting fertility, such as endometriosis or polycystic ovarian syndrome (PCOS), you can reasonably expect to get pregnant in your 20s with relative ease. Your risks of miscarriage, pregnancy complications, and genetic problems with your baby are also lowest in your 20s, given that you are overall healthy.
Getting Pregnant in Your 30s
Women between the ages of 30 and 35 still have a reasonably high chance of getting pregnant. However, your fertility has already begun to decline by the time you turn 30. After the age of 30, your chances of pregnancy decline by about 3% each year.
Most significantly, your fertility drops sharply after the age of 35. At age 37, you can expect to have just 25,000 eggs — 2.5% of your starting count. The risks of getting pregnant are also higher after age 35. By age 35, you are more likely to experience miscarriage, pregnancy complications, and genetic abnormalities of the fetus. For more information on getting pregnant in your 30s, check out our blog post here.
Getting Pregnant in Your 40s
You are significantly less likely to get pregnant in your 40s than in your 20s or early 30s. By age 40, your chances of getting pregnant are only 5% during each menstrual cycle, compared with 25% per cycle during your 20s. Your odds of miscarriage, pregnancy complications, and birth defects (such as Down syndrome) are also highest in your 40s.
In your 40s, you may only have a few years if you want to get pregnant naturally. By age 45, the American College of Obstetricians and Gynecologists says that getting pregnant naturally is unlikely for most women. After age 45, you will probably need to use assisted reproductive technology, such as in-vitro fertilization (IVF), to get pregnant. For more information on getting pregnant in your 40s, check out our blog post here.
The Role of Age in Fertility
Age plays an important role in fertility. Your chances of being able to get pregnant naturally start to lower slightly in your late 20s, and considerably in your late 30s. Once you hit 40, your chances of conceiving can drop to 5-10%. By the age of 45, the chance of pregnancy drops to less than 5%.
These are statistics for the general population, but there’s always room for outliers. There are instances where a 24-year-old can be struggling to conceive, while older women approaching menopause can have an unexpected pregnancy.
It’s essential to understand how your age impacts your fertility when you are trying to conceive (TTC) or thinking about conceiving soon. Here are some of the ways in which your age may impact the risks of pregnancy.
The risk of having a miscarriage in your 40s is nearly 50%, more than three times that of a woman in her 20s. The younger you are, the less likely you are to miscarry, given that you are otherwise healthy. That’s because the genetic mutations that cause most miscarriages become more common as women age. It’s estimated that half of all miscarriages are caused by extra or missing chromosomes.
Certain complications in the mom or the baby become more common as women age. For example:
- Preeclampsia is a syndrome combining high blood pressure with signs of kidney and liver damage during pregnancy. It is more common in mothers aged 40 and older.
- Premature birth (birth before 37 weeks gestation) frequently causes low birth weight, which can lead to complications in the health of the infant. Research suggests that women over age 40 are more likely to give birth prematurely.
- Some women develop high blood sugar during pregnancy, known as gestational diabetes, which increases their risk of developing type II diabetes later in life. Compared with women ages 20 to 29, women in their 40s are three to six times more likely to develop gestational diabetes.
- Sometimes, pregnancies may implant outside the uterus, most commonly in the fallopian tubes. These pregnancies are not viable due to growth restriction and can threaten the mother’s life if they cause the fallopian tubes to rupture. Women over 40 are at the highest risk of having an ectopic pregnancy when compared to women in other demographics.
Birth defects are most often caused by genetic abnormalities in the egg that becomes fertilized. As we stated previously, these genetic abnormalities become more common in a woman’s eggs as she gets older.
The most common types of genetic abnormalities affect chromosomes. Normally, babies are born with two copies of each chromosome and when a baby is born with too many or too few chromosomes, they may develop health problems, such as learning disabilities or structural defects in the organs.
Down Syndrome, caused by an extra copy of chromosome 21 (known as trisomy 21), is one of the most well-known genetic birth defects. Mothers over the age of 40 are significantly more likely to give birth to a baby with Down Syndrome. By the age of 40, your odds of giving birth to a baby with Down syndrome are 1 in 70; by age 45, the odds increase to 1 in 19.
Your age — alongside other factors, such as your overall health and fertility — may affect whether or not you are able to get pregnant naturally. Whether you are in your 20s and looking to conserve your fertility or in your 30s or 40s trying to get pregnant with the help of assisted reproductive technology, here are some treatments to consider.
Medically-speaking, the optimal time to have a baby is in your early 20s. However, many women are not ready to conceive until much later in life. If you are approaching 35 and are not ready to have a baby, or have a progressive health condition that may impact your fertility as you age, you may consider freezing your eggs to be fertilized later on. Egg freezing can improve your odds of pregnancy later in life, but it is also an expensive, invasive procedure that may cause side effects. Your doctor can advise you if freezing your eggs may be the right decision for you.
Women who are struggling to get pregnant naturally may have success with in-vitro fertilization (IVF), either with their own eggs or with eggs from a donor. The process can be expensive and tiresome, but many women in their 30s and 40s have success with IVF.
Furthermore, using donor eggs in IVF can improve your odds of pregnancy significantly if you are an older mother. That being said, many women prefer to try other methods before turning to IVF. The Mira fertility tracker may help you get pregnant naturally by helping you pinpoint the exact date of ovulation, through measuring your fertility hormone concentrations.
Every woman is born with a finite amount of eggs and as you age the quality and quantity of your eggs decrease, making it more difficult to get pregnant. Fortunately, a healthy lifestyle can help prevent some of the things that can impede pregnancy: obesity, underweight, stress, high blood pressure, and malnutrition. The key takeaway is that staying healthy maximizes your chance of a successful pregnancy, but won’t cancel out the effects of aging on the reproductive system.
When to Get Help
The process of TTC can feel exhausting and frustrating at times, no matter how old you are. However, most women do not need to worry if it takes them a while to get pregnant. Women who are under the age of 35 and have been trying for at least one year, or women older than 35 who have been trying for at least six months, should consult a fertility specialist for help getting pregnant. You should also talk to your doctor if you want to conceive but have a health condition that may impact your fertility, such as endometriosis or PCOS.
✔️ Medically Reviewed by Banafsheh Kashani, MD, FACOG
Banafsheh Kashani, M.D., FACOG is a board-certified OB/GYN and specialist in reproductive endocrinology and infertility at Eden Fertility Centers, and has been treating couples and individuals with infertility since 2014. Prior to joining Eden Centers for Advanced Fertility, she was practicing as a top fertility specialist at Kaiser Permanente in Orange County and Reproductive Fertility Center. Dr. Kashani has received numerous awards throughout her years of study and medical training.
Dr. Kashani has conducted extensive research in female reproduction, with a specific focus on the endometrium and implantation. Additionally, Dr. Kashani has authored papers in the areas of fertility preservation, and fertility in women with PCOS and Turners syndrome. She also was part of a large SART-CORS study evaluating the trend in frozen embryo transfers and success rates.
Dr. Kashani is a fellow of the American Congress of Obstetricians and Gynecologists. In addition, she is a diplomat of the American Board of Obstetrics and Gynecology and an active member of the American Society of Reproductive Medicine (ASRM) and Pacific Coast Reproductive Society (PCRS). She is also a member of the Society of Reproductive Endocrinology and Infertility (SREI).