A 45-year-old woman can get pregnant, but the path to conception is significantly more challenging and medically complex than it is for younger women. While modern medicine offers options to assist with conception at this age, the biological realities of reproductive aging make natural pregnancy increasingly rare. For women in this age group, understanding the decline in ovarian function and the associated health risks is a necessary part of family planning.
Biological Changes Affecting Conception
The primary biological factor limiting conception at age 45 is the rapid decline in ovarian function, affecting both the quantity and quality of a woman’s eggs. A woman is born with her entire lifetime supply of oocytes, and this ovarian reserve diminishes steadily over time. By age 45, the remaining pool of follicles is critically low, often numbering only around 1,000, which significantly limits the chance of releasing a viable egg each cycle.
The more substantial obstacle is the severe decline in egg quality due to accumulated genetic errors. As oocytes age, the cellular machinery responsible for proper chromosome separation deteriorates, resulting in a much higher incidence of aneuploidy. This means the egg has an incorrect number of chromosomes, which is the leading cause of failed implantation, miscarriage, and genetic syndromes. By age 45, the vast majority of a woman’s eggs may be chromosomally abnormal, leaving few viable for a healthy pregnancy.
Natural Conception Rates and Statistical Probability
The biological challenges translate into extremely low statistical odds for a natural, successful pregnancy and live birth at age 45. The chance of conceiving naturally in any given menstrual cycle is estimated to be less than 1%. Even when conception occurs, the risk of the pregnancy failing is substantial due to the high rate of chromosomal abnormalities.
The risk of miscarriage rises dramatically, reported to be well over 50% for women aged 45 and older, compared to less than 15% for women in their twenties. This high rate of pregnancy loss is directly linked to poor egg quality. The probability of achieving a live birth after an In Vitro Fertilization (IVF) cycle using one’s own eggs also drops significantly, often falling to less than 5%. This statistical reality highlights why many women seeking pregnancy turn to assisted reproductive technologies, particularly those utilizing younger eggs.
Health Risks for Mother and Baby
Once a pregnancy is achieved at age 45, it is classified as a pregnancy of Advanced Maternal Age (AMA) and is associated with increased health risks for both the mother and the baby. The mother faces higher risks of developing serious medical complications. These complications include a greater likelihood of gestational hypertension and preeclampsia, a condition characterized by high blood pressure and signs of organ damage.
Gestational diabetes is also more common, requiring careful monitoring and management. Furthermore, women in this age group have an increased chance of placental issues, such as placenta previa, and a higher overall rate of requiring a Cesarean section for delivery. The elevated risk profile means that pregnancies at age 45 are typically managed with more frequent prenatal visits and testing.
For the baby, the primary concern is the increased risk of chromosomal conditions, such as Down syndrome (Trisomy 21), a direct consequence of aged oocyte quality. The risk of having a baby with a chromosomal abnormality at age 45 is estimated to be around 1 in 35. Beyond genetic concerns, the baby also faces a higher risk of prematurity, defined as birth before 37 weeks of gestation, and low birth weight. These risks necessitate specialized prenatal care, including genetic screening and frequent ultrasounds.
Medical Interventions for Conception
Given the low probability of natural conception, Assisted Reproductive Technology (ART) becomes the most viable pathway for women attempting to get pregnant at age 45. While In Vitro Fertilization (IVF) using a woman’s own eggs is an option, success rates are very low due to poor egg quality, with live birth rates per cycle often in the low single digits. To mitigate the risk of chromosomal abnormalities, Preimplantation Genetic Testing (PGT) can be performed on IVF embryos.
PGT screens the embryos for aneuploidy before transfer, improving the chance of selecting a chromosomally normal embryo for implantation. Despite this screening, the scarcity of genetically normal embryos remains the limiting factor when using eggs from a 45-year-old. Consequently, using donor eggs offers the highest probability of a successful pregnancy and live birth.
Donor eggs come from younger, carefully screened women, effectively bypassing the age-related decline in oocyte quality. The success rate for IVF using donor eggs remains high, often ranging from 35% to 60% per cycle, regardless of the recipient’s age. This approach provides the best chance for women at 45 to achieve a healthy pregnancy and is frequently the preferred medical recommendation.