About 1 in 8 women of reproductive age in the United States have difficulty getting or staying pregnant. CDC data from 2015–2019 puts the rate of impaired fecundity (a broad measure that includes trouble conceiving and carrying a pregnancy to term) at 13.4% among women ages 15 to 49, which translates to roughly 9.7 million women. Among married women in that same age range, 8.5% meet the stricter clinical definition of infertility.
What Counts as Infertility
Infertility is clinically defined as the inability to achieve a successful pregnancy based on a person’s medical history, age, physical findings, and diagnostic testing. For couples having regular unprotected sex with no known reproductive issues, the standard timeline for evaluation is 12 months of trying without success when the female partner is under 35, and 6 months when she is 35 or older. That shorter window for older patients reflects the sharper decline in fertility that begins in the mid-30s.
The term “impaired fecundity” is broader than infertility. It captures anyone who has difficulty getting pregnant or carrying a baby to term, regardless of marital status or how long they’ve been trying. That’s why the 13.4% figure is higher than the 8.5% infertility rate, which only counts married women who meet the clinical threshold.
How Age Affects the Numbers
Age is the single strongest predictor of fertility. A woman in her early to mid-20s has a 25–30% chance of conceiving in any given month. By 40, that monthly chance drops to around 5%. This decline isn’t gradual and linear. It accelerates noticeably after 35, driven largely by changes in egg quality and quantity.
The age effect shows up clearly in IVF outcomes as well. For women under 35 using their own eggs, the live birth rate per egg retrieval is 53.2%, according to 2023 national data from the Society for Assisted Reproductive Technology. For women 41 to 42, that rate falls to 13.2%. For women over 42, it drops to just 4.1%. These numbers reflect the biological reality that fertility treatments can improve the odds but can’t fully compensate for age-related changes in egg viability.
Male Infertility’s Role
Infertility is not primarily a women’s health issue. Roughly one-third of infertility cases are caused by male reproductive problems, one-third by female reproductive problems, and the remaining third by a combination of both partners’ issues or by factors that are never identified. Male-factor infertility can involve low sperm count, poor sperm motility, or structural problems that prevent sperm from reaching the egg. Despite this even split, men are less likely to be evaluated early in the process, which can delay diagnosis.
Secondary Infertility
Many people assume that having one child means getting pregnant again will be straightforward. Secondary infertility, the inability to conceive or carry a pregnancy after previously giving birth, affects about 11% of couples in the United States. That makes it roughly as common as primary infertility. Age is often a factor here too: a couple who had their first child at 30 may face a meaningfully different biological landscape trying for a second at 35 or 37. Changes in weight, hormonal shifts, new medical conditions, and declining sperm quality can all contribute.
Who Uses Fertility Services
About 13.7% of women ages 20 to 49 have used some form of fertility service, based on 2022–2023 data. That includes everything from diagnostic testing and ovulation-inducing medications to more intensive procedures like IVF. Among married and cohabiting women ages 15 to 49, 7.8% meet the clinical definition of infertility, meaning there is a sizable population of people who seek help even before reaching that threshold or who pursue services for reasons beyond a strict infertility diagnosis, such as fertility preservation or same-sex couples building families.
The Cost Barrier
Access to treatment remains uneven. A single IVF cycle in the United States costs between $15,000 and $20,000, covering ovarian stimulation, egg retrieval, and embryo transfer. Many patients need more than one cycle. Only a handful of states mandate that insurance plans cover fertility treatment, and even in those states, coverage varies widely by employer and plan type. The financial burden means that infertility treatment is disproportionately accessed by higher-income households, even though infertility itself cuts across all income levels and demographics.
The 13.4% impaired fecundity rate is a population-level snapshot, not a prediction for any individual. Your personal odds depend on age, underlying health conditions, lifestyle factors, and your partner’s reproductive health. What the numbers do make clear is that difficulty conceiving is common enough to be considered a routine part of reproductive medicine, not an outlier experience.