Fertility Q&A

By Kristin A Bendikson, MD, USC Fertility

How a patient’s ethnic background affects her chance of pregnancy, especially with in vitro fertilization (IVF), is a fascinating yet poorly studied area of research. According to a 1995 national survey of family growth, non-White married women were more likely to experience infertility than White married women, yet these same non-White women were less likely to receive any type of infertility treatment—especially treatment with assisted reproductive technologies.1

There is very little data in the literature examining ethnicity and its affect on pregnancy rates with IVF. Ethnic minorities compose a small percentage of patients in the nation’s IVF programs, making it relatively difficult to examine how they respond to various infertility treatments. In the few studies that have examined the affect of ethnicity on IVF pregnancy rates, differing outcomes have been found.

There have been only two published studies specifically comparing IVF success rates between African Americans and Whites. The results of these studies contradict each other, with one showing that Blacks had decreased pregnancy rates with IVF compared with Whites; the other found no difference in pregnancy outcomes with IVF between these two ethnic groups.2,3

Likewise there are only a few studies directly comparing IVF pregnancy outcomes between Indians and Whites.4,5,6 One showed a trend toward decreased pregnancy rates in Indian women and found that Indian women were significantly more likely to have their cycle canceled compared with White women. Another study found no significant difference in IVF pregnancy rates between Indians and Whites. A more recent study has shown that Asian ethnicity was an independent predictor of poor outcome with IVF.7

The first study comparing IVF outcomes among multiple ethnic groups was a retrospective study reviewing the cycles of 1,135 women undergoing IVF between 1994 and 1998 at three IVF centers in Boston.8 Only the first IVF cycle of each woman was reviewed. Whites made up the majority of the patients, constituting 91.5 percent. Blacks, Asians, and Hispanics accounted for 4 percent, 3 percent, and 1.5 percent of the patient population, respectively.

Blacks had a significantly increased number of total past pregnancies in comparison with White and Asian women; however, there was no difference in the previous live births among the ethnic groups. The mean duration of infertility was 58 months for Hispanics, significantly higher in comparison with 38 months and 35 months for Whites and Blacks, respectively. Although there was no significant difference among the various ethnicities for most causes of infertility, Black women were more likely to have a tubal factor as a cause of their infertility than White women (51 percent versus 22 percent).

The majority of IVF cycle characteristics was not influenced by the ethnicity of the patients, although Blacks and Asians had significantly higher levels of estradiol than Whites. There was no significant difference among ethnicities for any of the cycle outcomes. The rates of successful live births did not change with ethnicity.

There are many reasons for the differing results of all of these studies, including the fact that some studies were performed in states where IVF coverage is mandated by health insurance while other studies were not, which has an obvious impact on the breakdown of patient socioeconomic status. Some studies looked at all IVF cycles versus studying only the patients’ first IVF cycle. When multiple cycles are included in the analysis, data on IVF outcomes may be confounded by the results for patients who unsuccessfully underwent repetitive cycles of IVF. In addition many of these studies were limited by their retrospective nature and the small sample size of the ethnic minorities.

To better understand how ethnicity affects IVF outcome, it will be necessary to study a larger number of minority patients. In these studies it is important that all ethnicities be included. If racial differences do exist, IVF treatment protocols could be adjusted to improve the success rates for patients of all ethnic backgrounds, so further exploration in this area is necessary and very important.

References

1. National survey of family growth, 1995. National Center for Health Statistics. Series 23, No. 19, 1997.

2. Sharara FI, McClamrock HD. Differences in in vitro fertilization (IVF) outcome between White and Black women in an inner-city, university-based IVF program. Fertility and Sterility. 2000;73(6):1170-73.

3. Nichols JE Jr., Higdon HL 3rd, Crane MM 4th, Boone WR. Comparison of implantation and pregnancy rates in African American and White women in an assisted reproductive technology practice, Fertility and Sterility. 2001;76(1):80-84.

4. Mahmud G, Bernal AL, Yudkin P, Ledger W, Barlow DH. A controlled assessment of the in vitro fertilization performance of British women of Indian origin compared with White women. Fertility and Sterility. 1995;64(1):103-6.

5. Anand Kumar TC, Puri CP, Gopalkrishnan K, Hinduja IN. The in vitro fertilization and embryo transfer (IVF-ET) and gamete intrafallopian transfer (GIFT) program at the Institute for Research in Reproduction (ICRM) and the King Edward Memorial Hospital, Parel, Bombay, India [letter]. Journal of in Vitro Fertilization and Embryo Transfer. 1988;5:376-77.

6. Lashen H, Afnan M, Sharif K. A controlled comparison of ovarian response to controlled stimulation in first generation Asian women compared with White Caucasians undergoing in vitro fertilization. British Journal of Obstetrics and Gynaecology. 1999;106(5):407-9.

7. Purcell K, Schembri M, Frazier LM, et al. Asian ethnicity is associated with reduced pregnancy outcomes after assisted reproductive technology. Fertility and Sterility. 2007;87(2):297-302.

8. Bendikson K, Cramer DW, Vitonis A, Hornstein MD. Ethnic background and in vitro fertilization outcomes. International Journal of Gynaecology and Obstetrics. 2005;88(3):342-46.

Kristin A. Bendikson, MD, joined USC Fertility after finishing her residency at Harvard Medical School and completing her subspecialty training in reproductive endocrinology and infertility at the internationally renowned Center for Reproductive Medicine and Infertility at Cornell University Medical College, under the direction of Zev Rosenwaks, MD. Kristin holds the title of assistant professor of obstetrics and gynecology in the Division of Reproductive Endocrinology and Infertility at the University of Southern California Keck School of Medicine. She is currently the principal investigator of several research projects, including the study of zygote intrafallopian tube transfer for women of advanced reproductive age, aging of the uterine endometrium, and vitamin D and its role in infertility. Her goal is to provide the highest-quality care for her patients and to help them fulfill their desire of having a healthy baby. In addition, she strives to guide her patients throughout what can be a trying and difficult journey by providing them with the support and the personal attention they need. A fertility expert, teacher, and researcher, Kristin is also a married mother of two.

FAQ: Ethnicity and Fertility

Do I need a different fertility workup based on my ethnic background?

For the most part, the answer is no, although you may be required to undergo different genetic testing based on your ethnicity, as certain ethnic groups have higher risks of particular heritable diseases.

Am I at higher risk of having a particular fertility issue based on my ethnic background?

At this time we do not believe that women develop diminished ovarian reserve at different rates based on their ethnicity, although Black women are two to three times more likely to get uterine fibroids than other ethnic groups, and fibroids can sometimes affect one’s ability to conceive.

Will I receive different fertility treatments based on my ethnic background?

No, we currently do not have a great enough understanding of how ethnicity affects fertility, so your fertility treatment will not be altered on the basis of your ethnicity. The only exception is for polycystic ovarian syndrome (PCOS). Though the prevalence of PCOS does not seem to be affected by ethnicity, African-American, Caribbean Hispanic, UK-based South Asian, and US-based Mexican-American women are more likely to have insulin resistance than White women with PCOS, which, if present, may have an impact on treatment.