Ask the Experts about Infertility/Assisted Reproduction Technology from Medscape Ob/Gyn & Women's Health
 Age and In Vitro Fertilization Question
I have a 45-year-old patient who is considering having a baby. She is a G3P3. What are the latest statistics? She specifically wants to know what are her chances of conceiving at this age and if she does conceive, what are the chances of having a genetically healthy pregnancy outcome.
Response from Peter Kovacs, MD
Research and Scientific Coordinator, Kaali Institute IVF Center, Budapest, Hungary; Visiting Clinical Instructor, Albert Einstein College of Medicine, Bronx, NY
There are numerous factors that affect a woman's chance to conceive. The most important factor is probably age. The ideal age range for successful pregnancy is between 20 and 30 years. Several studies have shown that fecundity declines with age, and a reduction in the monthly fecundity can be observed as early as age 30. There is some further acceleration of the rate of declining fecundity after the age of 35. For women 40 years and older, however, the chance to conceive is reduced by 50% with each additional year, and by the mid-40s it approaches zero. [1]
This decline is mainly attributable to oocyte factors. With advanced age, there is an increased rate of meiotic errors that will result in abnormal oocytes. These eggs will not fertilize; if they do, the majority of the embryos will fail to implant. Most of the embryos that do implant despite the genetic defect will be lost during the first few weeks of pregnancy. Preimplantation genetic studies have shown that for all women a large proportion of embryos are genetically abnormal. Although the rate is "only" around 30% among younger women, it is as high as 80% to 85% among women older than 40. The risk of trisomy 21 among women 45 years and older is 1:10 if chorionic villus sampling results are evaluated 1:20 if amniocentesis results are evaluated, and 1:40 at birth. Spontaneous abortion rates are significantly higher (about 40%) in the older age group. This high rate of genetic errors is one of the reasons why in vitro fertilization (IVF) cycles have poor outcomes among older women.
There are other reasons as well. At birth, about 2 million primordial follicles in the ovaries exist, but their number steadily declines with age When no more follicles can be recruited during ovulation, women enter menopause. The change from being reproductively active to menopausal is not abrupt and occurs over several years. During the perimenopausal transition, it becomes increasingly difficult to recruit follicles, and in some cycles it just does not happen. With respect to assisted reproductive technologies (ART), ovarian resistance to stimulation can occur during controlled ovarian hyperstimulation in perimenopausal women Despite the high doses of exogenous gonadotropins, few follicles can be induced to grow, and few eggs will be retrieved so that very often appropriate embryo selection and the transfer of morphologically good-quality embryos cannot occur.
The net effect of these factors will influence IVF outcome. In most countries, outcome is not required to be reported for women 42 years and older. On the basis of available reports and on the experience of infertility specialists, it is rather rare for a 43- or 44-year-old to conceive, and the situation is even worse for a 45-year-old. Even if her ovarian reserve testing yields good results and she successfully completes IVF treatment, her chances of conception will not be higher than 1% to 2% She would also face the increased risk of spontaneous abortion. The American Society for Reproductive Medicine reported a 7.1% delivery rate per initiated ART cycle among women 41 years and older on the basis of 1997 data. One would have to believe that most of these pregnancies occurred among the 41- and 42-year-old women. The rate of pregnancy loss was 41.6% in this age group. [2] More recently, the Centers for Disease Control and Prevention reported a 6% live birth rate for women 42 years of age and older undergoing ART whether or not they had had previous ART or a previous birth. [3] If there is no medical or other contraindication, an older woman is a good candidate for donor eggs, ; and her chances of successful pregnancy would be similar to that for a younger woman. [4]
IVF with donor eggs would be the best solution for the patient described in the question. If a donor oocyte is not acceptable to her, ovarian reserve should be evaluated, and if the testing reveals normal function, she could attempt a cycle of IVF. She needs to be informed about expected poor outcome, however, before the stimulation protocol is initiated. Posted 03/25/2004
References - Pal L, Santoro N. Age-related decline in fertility. Endocrinol Metab Clin North Am. 2003;32:669-688. Abstract
- Assisted reproductive technology in the United States: 1997 results generated from the American Society for Reproductive Medicine/Society for Assisted Reproductive Technology Registry. Fertil Steril. 2000;74:641-653. Abstract
- MMWR Surveill Summ. 2003;52:1-16. Available at: http://www.cdc.gov/mmwr/preview/mmwrhtml/ss5209a1.htm Accessed March 18, 2004.
- Toner JP, Grainger DA, Frazier LM. Clinical outcomes among recipients of donated eggs: an analysis of the U.S. national experience, 1996-1998. Fertil Steril. 2002;78:1038-1045. Abstract
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Age and In Vitro Fertilization