Most women lose the ability to get pregnant naturally somewhere between ages 41 and 46, though the exact cutoff varies widely from person to person. The average age of menopause is 51, but fertility typically ends 5 to 10 years before that, meaning natural conception becomes extremely unlikely by the mid-40s for most women. With medical help, pregnancy is possible later, but the options, risks, and odds change dramatically with each passing year.
Natural Fertility by Age
A woman’s fertility doesn’t drop off a cliff at a single age. It declines gradually, then accelerates. At 25, roughly 3.5% of women are infertile. By 40, that number jumps to 33%. By 45, about 87% of women can no longer conceive naturally. In populations where birth control isn’t used, the average age at which women have their last child falls around 42 to 43.
These numbers reflect egg quantity and quality. Women are born with all the eggs they’ll ever have, and both the number and the genetic integrity of those eggs decline over time. By your early 40s, a higher proportion of your remaining eggs carry chromosomal errors, which makes conception harder and miscarriage more likely even when fertilization does occur.
Natural pregnancies past 45 are rare but not impossible. The oldest verified natural conception on record belongs to Dawn Brooke of the UK, who gave birth at age 59 in 1997 after conceiving accidentally. Cases like hers are extreme outliers, not a realistic benchmark.
How IVF Changes the Picture
IVF extends the window somewhat, but success rates with your own eggs drop steeply after 40. At 40, the average live birth rate per IVF cycle is about 15 to 20%. By 43, that falls to roughly 5%. Past 45, success with your own eggs drops below 1% per cycle.
There’s no universal age cutoff for IVF treatment. Most clinics limit IVF with a patient’s own eggs to somewhere in the mid-40s, but decisions are made case by case based on overall health, egg reserve, and egg quality. A 44-year-old in excellent health with measurable ovarian reserve may still be offered treatment. A 42-year-old with no remaining viable eggs may not.
The limiting factor at this stage isn’t the uterus. A healthy uterus can carry a pregnancy well into the late 40s or even 50s. The bottleneck is egg quality, which is why donor eggs become the primary path for women past their mid-40s.
Donor Eggs After 45
Using eggs from a younger donor removes the age-related egg quality problem entirely. The live birth rate with fresh donor eggs is around 54% per cycle for recipients under 40, and success rates remain significantly higher than own-egg IVF at every recipient age. About 25% of women over 40 who successfully had a baby through IVF did so using donor eggs.
Because the uterus ages more slowly than the ovaries, donor egg IVF allows pregnancies into the late 40s and occasionally the early 50s. Some clinics will treat patients in this age range if they pass comprehensive health screenings. The pregnancy itself carries higher risks at these ages (more on that below), so screening is thorough and ongoing.
Frozen eggs offer a similar option. If you froze your own eggs at a younger age, those eggs retain the quality they had when they were retrieved, regardless of how old you are when you use them.
Chromosomal Risks Rise Sharply
The chance of a baby having a chromosomal abnormality increases with maternal age, driven almost entirely by egg quality. At 35, the risk of any detectable chromosomal abnormality is about 0.6%. At 40, it’s 1.6%. At 45, it jumps to 5.4%, roughly a 1-in-19 chance.
These figures include conditions like Down syndrome and other trisomies. Prenatal screening options, including blood tests and ultrasound measurements in the first trimester, can assess this risk early in pregnancy. More definitive testing through procedures like amniocentesis is available regardless of age. These are offered to all pregnant women, though the conversation takes on more weight when you’re over 35 or 40.
Health Risks for the Mother
Pregnancy after 45 carries meaningfully higher risks compared to younger pregnancies. A large systematic review found that women 45 and older face increased rates of preeclampsia (dangerous high blood pressure), gestational diabetes, placenta previa (where the placenta covers the cervix), placental abruption, postpartum hemorrhage, and preterm birth. The cesarean delivery rate is also substantially higher.
These risks don’t appear suddenly at 45. They climb gradually from the late 30s onward, which is why medical guidelines now break maternal age into five-year brackets: 35 to 39, 40 to 44, 45 to 49, and 50 and older. Each bracket carries progressively higher risk. A healthy 46-year-old can have a safe pregnancy, but it requires closer monitoring than the same pregnancy would at 36.
Pre-existing conditions matter too. High blood pressure, diabetes, and obesity all become more common with age, and each one compounds the risks of pregnancy. This is a major reason fertility clinics screen older patients carefully before proceeding with treatment.
A Realistic Timeline
If you’re trying to pin down practical age ranges, here’s how fertility breaks down for most women:
- Under 35: Highest natural fertility. Monthly conception rates are at their peak, and IVF success rates are strongest.
- 35 to 39: Fertility is declining but natural conception is still common. IVF remains effective.
- 40 to 43: Natural conception is possible but less likely. IVF with your own eggs still works for some women, though success rates are dropping fast.
- 44 to 46: Natural conception is very unlikely. IVF with your own eggs has minimal success. Donor eggs become the primary option.
- 47 and older: Natural conception is extremely rare. Pregnancy is generally only possible through donor eggs or previously frozen embryos, and requires careful health screening.
These ranges are averages. Some women run out of viable eggs at 38; others ovulate into their late 40s. Ovarian reserve testing can give you a snapshot of where you stand individually, though it measures egg quantity better than egg quality. The only reliable predictor of egg quality is age itself.