Do women with unexplained recurrent pregnancy loss have higher day 3 serum FSH and estradiol values?

FERTILITY AND STERILITY威 VOL. 74, NO. 2, AUGUST 2000 Copyright ©2000 American Society for Reproductive Medicine Published by Elsevier Science Inc. Printed on acid-free paper in U.S.A.

Do women with unexplained recurrent pregnancy loss have higher day 3 serum FSH and estradiol values? Susan W. Trout, M.D., and David B. Seifer, M.D. Division of Reproductive Endocrinology and Infertility, UMDNJ-Robert Wood Johnson Medical School, New Brunswick, New Jersey

Received November 2, 1999; accepted March 7. 2000. Supported by the Samuel A. Pasquale, MD Research Award, UMDNJ-Robert Wood Johnson Medical School, New Brunswick, NJ (Dr. Trout) and grant AG15425 from the National Institute on Aging, National Institutes of Health (Dr. Seifer). Presented in part at the American Society for Reproductive Medicine/ Canadian Fertility and Andrology Society Conjoint Annual Meeting, Toronto, Ontario, Canada, September 25–30, 1999. Reprint requests: Susan W. Trout, MD, University Center for Reproductive Endocrinology and Fertility, 303 George Street, Suite 250, New Brunswick, New Jersey 08901 (FAX: 732235-7318; E-mail: troutsw @umdnj.edu). 0015-0282/00/$20.00 PII S0015-0282(00)00625-7

Objective: To determine the potential role of diminished ovarian reserve in unexplained habitual abortion. Design: Retrospective comparative analysis. Setting: University-based practice. Patient(s): Fifty-seven women who presented for evaluation of recurrent pregnancy loss (RPL). Intervention(s): The test group (n ⫽ 36) comprised women with unexplained RPL. The control group (n ⫽ 21) comprised women with a known cause of RPL. Mean age, parity, day 3 serum FSH and E2 levels, and presence or absence of a history of infertility were compared between groups. Main Outcome Measure(s): Day 3 serum FSH and E2 levels. Result(s): Both day 3 FSH and E2 levels were elevated in the unexplained group compared with the control group. When combined, FSH or E2 levels, or both, were elevated in 58% of the unexplained RPL group and 19% of the control group (odds ratio, 5.95 [95% CI, 1.7–21.3]; P⬍.004). Age, parity, and presence of infertility did not differ between groups. Conclusion(s): Women with unexplained RPL have a greater incidence of elevated day 3 serum FSH and E2 levels than do women with a known cause of RPL. Therefore, diminished ovarian reserve may contribute to recurrent pregnancy loss and should be considered part of the work-up for RPL. (Fertil Steril威 2000;74:335–7. ©2000 by American Society for Reproductive Medicine.) Key Words: Habitual abortion, recurrent pregnancy loss, ovarian reserve

Approximately 1 in every 200 couples has recurrent pregnancy loss (RPL), as defined by multiple (ⱖ3) first-trimester spontaneous abortions. It is known that anatomical defects (8%); genetic factors (4%); autoimmune diseases, such as the antiphospholipid syndrome (3%); and endocrinopathies (8%) can cause RPL. Some women are found to have more than one cause (7%) (1). Unfortunately, no determinable cause can be found in most couples with recurrent miscarriage (70%). Women with unexplained RPL probably represent a heterogeneous group with several contributing causes. Among these causes are oocyte factors, endometrial factors, and possibly sperm factors (2– 4). It is well known that fetal aneuploidy can result in first-trimester spontaneous abortions and is more common in older women with poorer ovarian reserve (5). In addition, just as women enter menopause at different ages, re-

ductions in ovarian reserve seem to occur at different rates (6). Such factors as pelvic surgery, chemotherapy, and radiotherapy, as well as unknown factors that may directly affect the ovary, can adversely affect ovarian reserve. Therefore, even young women with recurrent miscarriage may have diminished ovarian reserve. Because diminished ovarian reserve is not limited to older women and can contribute to first-trimester spontaneous abortion, we examined the possible link between diminished ovarian reserve and RPL. We tested the hypothesis that diminished ovarian reserve, as reflected by elevated day 3 serum FSH and E2 levels, may contribute to RPL.

MATERIALS AND METHODS The records of all 67 women who were evaluated for habitual spontaneous abortion at the Pregnancy Loss Evaluation Service of St. 335

TABLE 1 Elevated day 3 serum levels of FSH and E2 in women with unexplained recurrent pregnancy loss and those with explained recurrent pregnancy loss. Variable No. (%) No. (%) No. (%) day 3

with with with FSH

day 3 FSH level ⱖ10 mIU/mL day 3 E2 level ⱖ50 pg/mL day 3 E2 level ⱖ50 pg/mL and/or level ⱖ10 mIU/mL

Women with unexplained RPL (n ⫽ 36)

Women with explained RPL (controls) (n ⫽ 21)

P value

11 (31%) 14 (39%)

1 (5%) 3 (14%)

⬍.02 .05

21 (58%)

4 (19%)

⬍.004

Note: RPL ⫽ recurrent pregnancy loss. Trout. Unexplained recurrent pregnancy loss and ovarian reserve. Fertil Steril 2000.

Peters University Hospital between July 1996 and September 1999 were assessed. Women with ⱖ3 first-trimester spontaneous abortions who had had a complete work-up (including day 3 FSH and E2 levels) were included in the analysis (n ⫽ 57). These women were assigned to one of two groups. One group (n ⫽ 36) comprised women in whom all testing yielded unremarkable results and therefore were given a diagnosis of unexplained RPL. The other group (n ⫽ 21), which represented controls, consisted of women in whom the cause of miscarriages was known (such as uterine septum or the antiphospholipid syndrome). Day 3 serum levels of FSH and E2 were compared in the two groups. Each group was divided into women with an elevated day 3 levels of FSH or E2 and women in whom day 3 levels of either substance were not elevated. An elevated day 3 level was defined as a serum FSH level ⱖ10 mIU/mL or a serum E2 level ⱖ50 pg/mL. These criteria for elevated FSH and E2 levels were based on data from previous reports (7, 8) and have corresponded well clinically with ovarian reserve in our practice. The work-up performed by the Pregnancy Loss Evaluation Service consisted of a detailed history, which included a complete obstetrical history, a medical and surgical history, a family history, and gynecologic history, and review of symptoms. Levels of prolactin, TSH, lupus anticoagulant, anticardiolipin antibody, antinuclear antibody, and doublestranded DNA were measured in all women. In addition, leukocyte karyotyping was performed in both partners. Serum FSH and E2 levels were measured on the third day of the menstrual cycle, and a uterine evaluation was done by using hysteroscopy, sonohysterography, or hysterosalpingography. A pathologist specializing in placental pathology also evaluated all available pathology specimens from the previous pregnancies. If no cause could be found for the pregnancy losses after this evaluation, the woman was assigned the diagnosis of unexplained RPL. Demographic data, including age, pregnancy history and history of infertility treatment, were recorded. Day 3 serum FSH and E2 levels and the method used to measure each substance were also recorded. 336

Trout and Seifer

Ovarian reserve in habitual abortion

Because FSH and E2 measurements were performed in two different laboratories by using either the Abbott IMX microparticle enzyme immunoassay (Abbott Laboratories, Abbott Park, IL) or the Immulite chemiluminescent enzyme immunoassay (Los Angeles, CA), all FSH levels were converted to the World Health Organization International Standard for FSH, number 78/549. The laboratories could not supply a similar standard for E2 levels; they were therefore converted to values given by the Immulite method because that was the method by which most (72%) of the samples had been measured. Formulas for conversion were calculated by comparing the standard curves of E2 run by the two methods. The coefficient of variation of the estradiol assays was 8.1% for the Immulite method and 8.4% for the Abbott IMX system. Data were compared by using the ␹2 or Fisher exact test, as appropriate. A P value of 0.05 was considered statistically significant. Odds ratios and confidence intervals were calculated by using EpiInfo software, version 6.04a (Centers for Disease Control and Prevention, Atlanta, GA). The study was approved by the Institutional Review Boards of St. Peters University Hospital and the University of Medicine and Dentistry of New Jersey.

RESULTS Of the 36 women with unexplained RPL, 21 (58%) had elevated serum levels of FSH or E2 levels on day 3. Of these 21 women, 14 had elevated E2 levels, 11 had elevated FSH levels. Four of the 21 women (19%) in the control group had an elevated serum levels of FSH or E2 on day 3. One of the 4 had an elevated 3 FSH levels and 3 had elevated E2 levels. The percentage of women with elevated FSH levels (P⬍ .02), elevated E2 levels (P⫽.05), and elevated FSH and E2 (P⬍.004) levels on day 3 was significant (Table 1). The odds ratio for having an elevated serum level of FSH or E2 (or both) was 5.95 (95% CI, 1.7–21.3). The mean (⫾) age did not differ significantly between the unexplained RPL group and the control group (36 ⫾ 5 vs. 35 ⫾ 5 years). The average number of miscarriages also did Vol. 74, No. 2, August 2000

not differ significantly between groups. Fifteen of the women with elevated day 3 levels and 16 of those with normal day 3 level had a history of infertility; this difference was not statistically significant. The number of women in the unexplained RPL group and the control group who had infertility did not differ significantly.

DISCUSSION To our knowledge, this is the first study to examine the role of ovarian reserve in unexplained RPL. Our data show that unexplained RPL is associated with diminished ovarian reserve, as measured by serum day 3 FSH and E2 levels. The odds ratio for an elevated serum level of FSH or E2 was 5.95 (95% CI, 1.7–21.3). Thus, women who had unexplained RPL were approximately six times more likely than women with an identifiable cause of RPL to have an elevated day 3 serum level of FSH or E2. Of note, 19% of women with an identifiable cause of RPL had an elevated day 3 FSH or E2 level. It is possible that diminished ovarian reserve was an additional contributing cause to the outcomes of these pregnancies. Ovarian reserve diminishes with age. It may therefore be more cost effective to test only women ⬎34 years of age by measuring day 3 FSH and E2 levels. To test this hypothesis, we reviewed the ages of women with elevated day 3 FSH and E2 levels. If we had measured FSH and E2 levels only in women ⬎34 years of age, we would have missed 24% of the women who had elevated values. It therefore seems prudent to test for diminished ovarian reserve in all women who present for evaluation. Day 3 serum levels of FSH and E2 are an indirect measure of ovarian reserve. As oocyte quality and quantity declines, serum basal FSH levels increase (9). Basal FSH levels measured on day 2– 4 of the menstrual cycle have been shown to be better than age alone in predicting pregnancy rate after in vitro fertilization (10, 11). Basal E2 levels may provide additional useful information: high E2 levels indicate an

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accelerated rate of follicular development, which is often seen in the perimenopause (10). High levels of E2 will also decrease FSH levels, leading to a falsely reassuring test if only FSH is tested. Recently, it was shown that day 3 FSH and E2 levels predict fetal aneuploidy (7). It is possible that some women with recurrent miscarriage have poorer quality oocytes with inherent chromosomal compromise. Currently, 70% of cases of RPL remain unexplained. We believe that diminished ovarian reserve may contribute in part to unexplained recurrent abortions. Consideration should be given to measuring day 3 serum FSH and E2 during evaluation of a couple presenting with recurrent miscarriage. References 1. Tho PT, Byrd Jr, McDonough PG. Etiologies and subsequent reproductive performance of 100 couples with recurrent abortion. Fertil Steril 1979;32:389 –95. 2. Buckett WM, Luckas MJM, Aird IA, Farquharson RG, Kingsland CR, Lewis-Jones DI. The hypo-osmotic swelling test in recurrent miscarriage. Fertil Steril 1997;68:506 –9. 3. Kiefer D, Check JH, Katsoff D. Evidence that oligoasthenozoospermia may be an etiologic factor for spontaneous abortion after in vitro fertilization-embryo transfer. Fertil Steril 1997;68:545– 8. 4. Rubio C, Simon C, Blanco J, Vidal F, Minguez Y, Egozcue J, Crespo J, et al. Implications of sperm chromosome abnormalities in recurrent miscarriage. J Assist Reprod Genet 1999;16:253– 8. 5. Wilcox AJ, Weinberg CR, O’Conner JF, et al. Incidence of early loss of pregnancy. N Engl J Med 319:189 –94. 6. Gindoff PR, Schmidt PJ, Rubinow DR. Response to clomiphene citrate challenge test in normal women through perimenopause. Gynecol Obstet Invest 1997;43:186 –91. 7. Nasseri A, Mukherjee T, Grifo JA, Noyes N, Krey L, Copperman AB. Elevated day 3 serum follicle stimulating hormone and/or estradiol may predict fetal aneuploidy. Fertil Steril 1999;71:715– 8. 8. Barnhart K, Osheroff J. Follicle stimulating hormone as a predictor of fertility. Curr Opin Obstet Gynecol 1998;10:227–32. 9. Lenton EA, Sexton L, Lee S, Cooke ID. Progressive changes in LH and FSH and LH:FSH ratio in women throughout reproductive life. Maturitas 1998;10:35– 43. 10. Scott RT, Toner JP, Muasher SJ, Oehninger S, et al. Follicle-stimulating hormone levels on cycle day 3 are predictive of in vitro fertilization outcome. Fertil Steril 1989;51:651– 4. 11. Magarelli PC, Pearlstone AC, Buyalos R. Discrimination between chronological and ovarian age in infertile women aged 35 and older: predicting pregnancy using basal follicle stimulating hormone, age and number of ovulation induction/intra-uterine insemination cycles. Hum Reprod 1996;11:1214 –9.

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