Determinants of basal follicle-stimulating hormone levels in premenopausal women

A 65-Year-Old Woman With No Menopause History: A Case Report

Menopause is a universal occurrence in a woman's life where menstruation ceases, with an average age of 51.4 years in the United States. Late-onset menopause is defined as menopause after age 55. A thorough PubMed search revealed that there are currently no records of extended cycles through the entirety of a woman's geriatric years. A 65-year-old G2P2 Caucasian woman was admitted to the emergency department (ER) with a possible cerebrovascular accident. During admission, it was noted that the patient had vaginal bleeding. CT scan revealed a large fibroid, and ultrasound revealed an extremely thin endometrium, excluding endometrial pathology. Gynecology was consulted for post-menopausal bleeding, but in interviewing the patient, she was not surprised at her bleeding. Her LH and FSH levels were low, in the premenopausal range. This is a cautionary tale of an appropriate workup, and the importance of taking a gynecologic history, in the geriatric population.

Pre-pregnancy body mass index and time to pregnancy among couples pregnant within a year: A China cohort study

Background

Extreme pre-pregnancy body mass index (BMI) values have been associated with reduced fecundability and prolonged time to pregnancy in previous studies. However, the effect in fertile couples is unclear.

Objectives

This study aimed to evaluate the association between pre-pregnancy BMI and fecundability, measured as time to pregnancy (TTP), among couples that achieved pregnancy within 1 year.

Methods

This was a retrospective cohort study of 50,927 couples wishing to conceive, enrolled in the National Free Preconception Health Examination Project (NFPHEP) in Chongqing, China, during 2012–2016. Participants’ weight and height were measured by NFPHEP-trained preconception guidance physicians. TTP measured in months was used to determine subfecundity (TTP >6 months). The strength of association between BMI and TTP/subfecundity was measured with fecundability odds ratios (FOR)/odds ratios (OR) and their corresponding 95% confidence intervals (CI), calculated with Cox and logistic regression analysis. We used restricted cubic spline regression (RCS) to test the observed FOR trends.

Results

Compared to women with normal BMI, women with pre-pregnancy overweight/obesity had longer TTP (FOR = 0.96, 95% CI: 0.94–0.99) and increased risk of subfecundity (OR = 1.08, 95% CI: 1.00–1.17). There was no association between TTP and male BMI. RCS trends varied when data were stratified by male pre-pregnancy BMI, with the greatest change detected in pre-pregnancy underweight men.

Conclusions

Pre-pregnancy overweight/obesity was associated with longer TTP and subfecundity among women who became pregnant within 1 year; this effect was likely mediated by their partners’ pre-pregnancy BMI. These findings indicate that BMI could affect fecundability, independently of affecting the risk of sterility. Advice on weight management and maintaining healthy weight should be included in couples’ preconception guidance.

In-utero cigarette smoke exposure and the risk of earlier menopause

OBJECTIVE

Cigarette smoking is a risk factor for earlier menopause. Animal studies show that in-utero smoke exposure is toxic to developing ovaries. Our aim was to evaluate whether in-utero smoke exposed women reach menopause earlier compared with nonexposed women.

METHODS

This is a cohort study within the Avon Longitudinal Study of Parents and Children. Participants included in this study were followed from 1991/1992 until 2010. Participant characteristics for the current analysis were obtained from obstetric records and from annual follow-up questionnaires. When not available, age at natural menopause was estimated by age at filling in the questionnaire minus 1 year. Cox proportional hazards modeling was used to estimate hazard ratios of menopause for in-utero exposed and nonexposed women.

RESULTS

There were 695/2,852 postmenopausal women, of whom 466 had natural menopause, 117 had hormonal therapy, and 112 had surgical menopause. Age at natural menopause was 50.6 ± 3.7 years. Of all participants, 20.2% (577/2,852) were exposed to smoke in-utero. Participants who were in-utero exposed but were not smokers did not have higher hazards of menopause (adjusted hazard ratio [HR] 0.92, 95% CI 0.72-1.18), whereas participants who were ever smokers (current or previous) and were in-utero exposed (adjusted HR 1.41, 95% CI 1.01-1.95) or were ever smokers but not exposed (adjusted HR 1.24, 95% CI 1.00-1.53) did have higher hazards of earlier menopause.

CONCLUSIONS

In-utero smoke exposure was not associated with earlier menopause, but the effect of in-utero smoke exposure was modified by the smoking habits of the participants themselves increasing the risk for smokers who were in-utero exposed.

Life course exposure to smoke and early menopause and menopausal transition

OBJECTIVE

Early age at menopause is associated with increased risk of cardiovascular disease, stroke, osteoporosis, and all-cause mortality. Cigarette smoke exposure in adulthood is an established risk factor for earlier age at natural menopause and may be related to age at the menopausal transition. Using data from two US birth cohorts, we examined the association between smoke exposure at various stages of the life course (prenatal exposure, childhood exposure to parental smoking, and adult smoke exposure) and menopause status in 1,001 women aged 39 to 49 years at follow-up.

METHODS

We used logistic regression analysis (adjusting for age at follow-up) to estimate odds ratios (ORs) and 95% confidence intervals (CI) relating smoke exposure to natural menopause and the menopausal transition.

RESULTS

The magnitudes of the associations for natural menopause were similar but not statistically significant after adjustment for confounders among (i) women with prenatal smoke exposure who did not smoke on adult follow-up (OR, 2.7; 95% CI, 0.8-9.4) and (ii) current adult smokers who were not exposed prenatally (OR, 2.8; 95% CI, 0.9-9.0). Women who had been exposed to prenatal smoke and were current smokers had three times the risk of experiencing earlier natural menopause (adjusted OR, 3.4; 95% CI, 1.1-10.3) compared with women without smoke exposure in either period. Only current smoking of long duration (>26 y) was associated with the timing of the menopausal transition.

CONCLUSIONS

Our data suggest that exposure to smoke both prenatally and around the time of menopause accelerates ovarian aging.

Active and passive smoking and fecundability in Danish pregnancy planners

OBJECTIVE

To investigate the extent to which fecundability is associated with active smoking, time since smoking cessation, and passive smoking.

DESIGN

Prospective cohort study.

SETTING

Denmark, 2007-2011.

PATIENT(S)

A total of 3,773 female pregnancy planners aged 18-40 years.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Self-reported pregnancy. Fecundability ratios (FRs) and 95% confidence intervals (CIs) were estimated using a proportional probabilities model that adjusted for menstrual cycle at risk and potential confounders.

RESULT(S)

Among current smokers, smoking duration of ≥10 years was associated with reduced fecundability compared with never smokers (FR, 0.85, 95% CI 0.72-1.00). Former smokers who had smoked ≥10 pack-years had reduced fecundability regardless of when they quit smoking (1-1.9 years FR, 0.83, 95% CI 0.54-1.27; ≥2 years FR, 0.73, 95% CI 0.53-1.02). Among never smokers, the FRs were 1.04 (95% CI 0.89-1.21) for passive smoking in early life and 0.92 (95% CI 0.82-1.03) for passive smoking in adulthood.

CONCLUSION(S)

Among Danish pregnancy planners, cumulative exposure to active cigarette smoking was associated with delayed conception among current and former smokers. Time since smoking cessation and passive smoking were not appreciably associated with fecundability.

Are the pituitary gonadotrophins determinants of complete molar pregnancy? An investigation using the method of least squares

Objective

To look for a relationship between the maternal age-specific incidence of complete molar pregnancy and the age-specific mid-follicular levels of circulating follicle stimulating hormone and luteinizing hormone.

Design

Calculation of correlation coefficients between the incidence of complete mole and the circulating levels of follicle stimulating hormone and luteinizing hormone using the method of least squares.

Setting

England and Wales.

Participants

All mothers between 23 and 49 years delivering in England and Wales between 2000 and 2009 inclusive and a sample of women between 23 and 49 years from Sheffield (1987).

Main outcome measures

The bivariate correlation coefficients between the incidence of complete mole and the mid-follicular plasma levels of the pituitary gonadotrophins.

Results

Exponential correlation between the incidence of complete mole and mid-follicular plasma follicle stimulating hormone, r = 0.965, r²= 0.932.

Linear correlation between the incidence of complete mole and mid-follicular plasma luteinizing hormone, r = 0.972, r²= 0.944.

Multivariate exponential regression between the incidence of complete mole and the combination of follicle stimulating and luteinizing hormones. This does not improve the prediction of the incidence of complete mole and it shows that luteinizing hormone is not a significant predictor of the incidence of complete mole in the presence of follicle stimulating hormone.

Conclusions

There is a strong positive exponential correlation between the maternal age-specific incidence of complete mole in England and Wales and the age-related mid-follicular levels of follicle stimulating hormone in a sample of English women.

Body size and time-to-pregnancy in black women

STUDY QUESTION

Are overall and central obesity associated with reduced fecundability in US black women?

SUMMARY ANSWER

Overall and central obesity--based on self-reported measures of body mass index (BMI, kg/m(2)), waist circumference and waist-to-hip ratio--were independent risk factors for subfertility in our cohort.

WHAT IS KNOWN ALREADY

Overall obesity (BMI ≥ 30 kg/m(2)) has been associated with infertility in several studies. The role of central obesity is less clear. There are no previous studies of time-to-pregnancy (TTP) in black women.

STUDY DESIGN, SIZE, DURATION

Data were derived from the Black Women's Health Study, a prospective cohort study. During 1995-2011, there were 2239 planned pregnancy attempts reported by 1697 women, resulting in 2022 births. Cohort retention was greater than 80%.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Eligible women were aged 21-40 years and reported at least one planned pregnancy attempt during 1995-2011. Height and weight were reported in 1995, with weight updated every two years; waist and hip circumferences were reported in 1995 and updated in 2003. A validation study within the cohort showed high correlations between self-reported and technician-measured weight (r = 0.97), height (r = 0.93), waist circumference (r = 0.75) and hip circumference (r = 0.74). In 2011, TTP was reported in months. Proportional probabilities regression models were used to estimate fecundability ratios (FRs) and 95% confidence intervals (CI), adjusting for covariates.

MAIN RESULTS AND THE ROLE OF CHANCE

High BMI was associated with delayed conception: relative to BMI 18.5-24.9, FRs for BMI categories of <18.5, 25.0-29.9, 30.0-34.9 and ≥ 35.0 were 0.92 (CI: 0.64-1.32), 0.93 (CI: 0.84-1.03), 0.92 (CI: 0.79-1.06) and 0.73 (CI: 0.61-0.87), respectively. Associations were stronger among nulliparous women (P-interaction = 0.003). After controlling for BMI, reduced fecundability was observed among women with large waist circumferences (≥ 33 versus <26 inches: FR = 0.73, CI: 0.60-0.88) and large waist-to-hip ratios (≥ 0.85 versus <0.71: FR = 0.83, CI: 0.71-0.97).

LIMITATIONS, REASONS FOR CAUTION

TTP was reported retrospectively and error in recall is likely, particularly as time since the pregnancy increases. However, results were similar when based on the most recent versus first pregnancies. Confounding may have been introduced by the lack of control for important determinants of TTP. Nevertheless, control for maternal age and education, which are highly correlated with TTP determinants such as paternal age and persistence in trying, should reduce the extent of confounding. The analysis was confined to planned pregnancies. If pregnancy intention was related both to body size and fecundability, our results could be biased. Bias is likely to be small because we found little difference in body size and other measured characteristics between pregnancy planners and non-planners.

WIDER IMPLICATIONS OF THE FINDINGS

Our findings add to the growing body of literature showing that excess BMI is associated with reduced fecundability and further suggest that central obesity is an important independent risk factor for infertility. The relation of obesity to infertility is especially relevant to US black women because they have higher rates of obesity and infertility. Reductions in overall and central obesity may offer the potential to improve fertility outcomes.

STUDY FUNDING/COMPETING INTEREST(S)

This work was funded by National Cancer Institute grant CA58420. We have no competing interests to report.

A prospective cohort study of physical activity and time to pregnancy

OBJECTIVE

To investigate the association between leisure-time physical activity (PA) and fecundability.

DESIGN

Prospective cohort study.

SETTING

Internet-based observational study of Danish women who were planning a pregnancy (2007-2009).

PATIENT(S)

A total of 3,628 women aged 18-40 years at baseline.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Time to pregnancy (TTP). Fecundability ratios (FRs) and 95% confidence intervals (CIs) were derived from discrete-time Cox models, with adjustment for potential confounders, such as body mass index (BMI).

RESULT(S)

We observed an inverse monotonic association between vigorous PA and fecundability (≥ 5 h/wk vs. none: FR 0.68, 95% CI 0.54-0.85) and a weak positive association between moderate PA and fecundability (≥ 5 vs. <1 h/wk: FR 1.18, 95% CI 0.98-1.43) after mutual adjustment for both PA types. Inverse associations between high vigorous PA and fecundability were observed within subgroups of age, parity status, and cycle regularity, but not among overweight or obese women (BMI ≥ 25 kg/m(2)).

CONCLUSION(S)

There was evidence for a dose-response relationship between increasing vigorous PA and delayed TTP in all subgroups of women with the exception of overweight and obese women. Moderate PA was associated with a small increase in fecundability regardless of BMI. These findings indicate that PA of any type might improve fertility among overweight and obese women, a subgroup at higher risk of infertility. Lean women who substitute vigorous PA with moderate PA may also improve their fertility.

A prospective cohort study of menstrual characteristics and time to pregnancy

The authors examined the association between menstrual characteristics and time to pregnancy among 2,653 Danish women enrolled in a prospective cohort study (2007-2009). Menstrual characteristics were reported at baseline. Outcome data were updated bimonthly until pregnancy, fertility treatment, loss to follow-up, or end of observation (12 cycles). Adjusted fecundability ratios and 95% confidence intervals were estimated by using discrete-time Cox regression models. Relative to average cycle lengths (27-29 days), fecundability ratios for cycle lengths <25, 25-26, 30-31, 32-33, and ≥34 days were 0.64 (95% confidence interval (CI): 0.49, 0.84), 0.94 (95% CI: 0.77, 1.13), 1.10 (95% CI: 0.97, 1.25), 1.35 (95% CI: 1.06, 1.73), and 1.17 (95% CI: 0.91, 1.49), respectively. Compared with cycles that regularized within 2 years after menarche, fecundability ratios for cycles that regularized 2-3 and ≥4 years after menarche were 0.90 (95% CI: 0.80, 1.02) and 0.89 (95% CI: 0.77, 1.03), respectively. Fecundability ratios were 0.87 (95% CI: 0.72, 1.05) comparing <3 with 3-4 days of menstrual bleeding and 0.70 (95% CI: 0.43, 1.13) comparing very heavy with moderate flow. In the present study, shorter cycle length was associated with delayed time to pregnancy. Age at menarche, time to menstrual regularization, and duration or intensity of menstrual flow were not appreciably associated with fecundability.

Antiovulatory and abortifacient effects of Areca catechu (betel nut) in female rats

Objectives:

To study the antiovulatory and abortifacient effects of ethanolic extract of Areca catechu in female rats.

Materials and Methods:

For antiovulatory effect, ethanolic extract of A. catechu at 100 and 300 mg/kg doses was administered orally for 15 days. Vaginal smears were examined daily microscopically for estrus cycle. Rats were sacrificed on 16^th day. Ovarian weight, cholesterol estimation, and histopathological studies were done. Abortifacient activity was studied in rats at 100 and 300 mg/kg doses administered orally from 6^th to 15^th day of pregnancy. Rats were laparotomised on 19^th day. The number of implantation sites and live fetuses were observed in both horns of the uterus.

Results:

The extract of A. catechu showed a significant decrease in the duration of estrus at 100 mg/kg (P = 0.015) and 300 mg/kg doses (P = 0.002) as compared with control. Metestrus phase was also significantly reduced at 100 mg/kg (P = 0.024) and 300 mg/kg doses (P = 0.002). There was a significant increase in proestrus (P < 0.001) phase. However, diestrus phase was unchanged. Histopathological study of the ovaries showed mainly primordial, primary, and secondary follicles in the test groups as compared to control. There was also a significant (P = 0.002) decrease in ovarian weight and a significant (P = 0.021) increase in ovarian cholesterol level at 100 mg/kg dose. In the study to evaluate abortifacient effect, the mean percentage of abortion with 100 and 300 mg/kg doses were 75.5% and 72.22%, respectively, which was significantly (P = 0.008 and P = 0.006, respectively) increased when compared with control.

Conclusion:

The ethanolic extract of A. catechu at doses of 100 and 300 mg/kg has antiovulatory and abortifacient effects.

Effect of hormone metabolism genotypes on steroid hormone levels and menopausal symptoms in a prospective population-based cohort of women experiencing the menopausal transition

OBJECTIVE

This study evaluated whether genes involved in the metabolism of steroid hormones are associated with hormone levels or menopausal symptoms.

METHODS

We used a population-based prospective sample of 436 African American (AA) and European American (EA) women who were premenopausal at enrollment and were followed longitudinally through menopause. We evaluated the relationship between steroid hormone metabolism genotypes at COMT, CYP1A2, CYP1B1, CYP3A4, CYP19, SULT1A1, and SULT1E1 with hormone levels and menopausal features.

RESULTS

In EA women, SULT1E1 variant carriers had lower levels of dehydroepiandrosterone sulfate, and SULT1A1 variant carriers had lower levels of estradiol, dehydroepiandrosterone sulfate, and testosterone compared with women who did not carry these variant alleles. In AA women, CYP1B1*3 genotypes were associated with hot flashes (odds ratio [OR], 0.62; 95% CI, 0.40-0.95). Interactions of CYP1A2 genotypes were associated with hot flashes across menopausal stage (P = 0.006). Interactions of CYP1B1*3 (P = 0.02) and CYP1B1*4 (P = 0.03) with menopausal stage were associated with depressive symptoms. In EA women, SULT1A1*3 was associated with depressive symptoms (OR, 0.53; 95% CI, 0.41-0.68) and hot flashes (OR, 2.08; 95% CI, 1.64-2.63). There were significant interactions between SULT1A1*3 and hot flashes (P < 0.001) and between SULT1A1*2 and depressive symptoms (P = 0.007) on menopausal stage, and there were race-specific effects of SULT1A1*2, SULT1A1*3, CYP1B1*3, and CYP3A4*1B on menopause.

CONCLUSIONS

Our results suggest that genotypes are associated with the occurrence of menopause-related symptoms or the timing of the menopausal transition.

Ovarian function and cigarette smoking

Cigarette smoking has been implicated in reproductive outcomes including delayed conception, but mechanisms underlying these associations remain unclear. One potential mechanism is the effect of cigarette smoking on reproductive hormones; however, studies evaluating associations between smoking and hormone levels are complicated by variability of hormones and timing of specimen collection. We evaluated smoking among women participating in the BioCycle Study, a longitudinal study of menstrual cycle function in healthy, premenopausal, regularly menstruating women (n = 259). Fertility monitors were used to help guide timing of specimen collection. Serum levels of oestradiol, progesterone, follicle-stimulating hormone (FSH), luteinising hormone (LH) and total sex-hormone binding globulin (SHBG) across phases of the menstrual cycle were compared between smokers and non-smokers. We observed statistically significant phase-specific differences in hormone levels between smokers and non-smokers. Compared with non-smokers, smokers had higher levels of FSH in the early follicular phase and higher LH at menses after adjusting for potential confounding factors of age, race, body mass index, parity, vigorous exercise, and alcohol and caffeine intake through inverse probability of treatment weights. No statistically significant differences were observed for oestradiol, progesterone or SHBG. These phase-specific differences in levels of LH and FSH in healthy, regularly menstruating women who are current smokers compared with non-smokers reflect one mechanism by which smoking may influence fertility and reproductive health.

The impact of smoking on antimüllerian hormone levels in women aged 38 to 50 years

OBJECTIVE

Smoking is associated with increased follicle-stimulating hormone levels and early menopause. Smoking may directly accelerate ovarian follicular depletion or may act indirectly by increasing the pituitary production of follicle-stimulating hormone. Antimüllerian hormone (AMH), produced by ovarian follicles, is a more direct measure of ovarian reserve. The objective of our study was to determine the extent to which smoking influences ovarian reserve, as measured by AMH levels.

METHODS

A community sample of 284 women aged 38 to 50 years completed a self-administered questionnaire including a detailed smoking history. Serum AMH levels were measured on day 2, 3, or 4 of the menstrual cycle. The association between AMH and smoking was analyzed using linear regression, adjusting for age and body mass index.

RESULTS

Participants aged 38 to 42, 43 to 45, and 46 to 50 years had geometric mean AMH values of 6.7 pM (95% CI, 5.2-8.7 pM), 2.7 pM (95% CI, 1.9-3.8 pM), and 1.3 pM (95% CI, 1.0-1.7 pM), respectively. Current smokers, but not past smokers, had 44% lower AMH values than did the reference group (participants with neither active nor former or passive smoke exposure; P = 0.04). Passive smoking had no effect on AMH values when compared with the reference group (P = 0.55). The impact of smoking on AMH values was not dose dependent based on cigarettes per day (P = 0.08) or pack-years (P = 0.22). Finally, prenatal exposure to smoking (either maternal or paternal) had no impact on AMH levels (P = 0.47 and P = 0.89, respectively).

CONCLUSIONS

Active smoking, but not former smoking, is associated with decreased AMH values in late-reproductive-age and perimenopausal women, suggesting a possible direct effect of smoking on the depletion of the antral but not primordial follicles. The direct impact of active smoking on AMH levels in younger women requires further investigation.

An internet-based prospective study of body size and time-to-pregnancy

BACKGROUND

Recent studies have shown that both female and male obesity may delay time-to-pregnancy (TTP). Little is known about central adiposity or weight gain and fecundability in women.

METHODS

We examined the association between anthropometric factors and TTP among 1651 Danish women participating in an internet-based prospective cohort study of pregnancy planners (2007-2008). We categorized body mass index (BMI = kg/m(2)) as underweight (<20), normal weight (20-24), overweight (25-29), obese (30-34) and very obese (> or =35). We used discrete-time Cox regression to estimate fecundability ratios (FRs) and 95% confidence intervals (CI), controlling for potential confounders.

RESULTS

We found longer TTPs for overweight (FR = 0.83, 95% CI = 0.70-1.00), obese (FR = 0.75, 95% CI = 0.58-0.97), and very obese (FR = 0.61, 95% CI = 0.42-0.88) women, compared with normal weight women. After further control for waist circumference, FRs for overweight, obese, and very obese women were 0.72 (95% CI = 0.58-0.90), 0.60 (95% CI = 0.42-0.85) and 0.48 (95% CI = 0.31-0.74), respectively. Underweight was associated with reduced fecundability among nulliparous women (FR = 0.82, 95% CI = 0.63-1.06) and increased fecundability among parous women (FR = 1.61, 95% CI = 1.08-2.39). Male BMI was not materially associated with TTP after control for female BMI. Compared with women who maintained a stable weight since age 17 (-5 to 4 kg), women who gained > or =15 kg had longer TTPs (FR = 0.72, 95% CI = 0.59-0.88) after adjustment for BMI at age 17. Associations of waist circumference and waist-to-hip ratio with TTP depended on adjustment for female BMI: null associations were observed before adjustment for BMI and weakly positive associations were observed after adjustment for BMI.

CONCLUSIONS

Our results confirm previous studies showing reduced fertility in overweight and obese women. The association between underweight and fecundability varied by parity.

Lifestyle and reproductive factors associated with follicular phase length

PURPOSE

Variability in menstrual cycle length, largely determined by variation in follicular phase length, is related to several health outcomes, yet the causes of this variability are incompletely understood. We sought to identify characteristics associated with follicular phase length.

METHODS

We used the North Carolina Early Pregnancy Study to describe factors correlated with timing of ovulation (follicular phase length). Women collected daily urine specimens and recorded vaginal bleeding. Specimens were assayed for estrone 3-glucuronide and pregnanediol 3-glucuronide, which in turn were used to estimate the day of ovulation. All other variables were assessed through interview. Associations with follicular phase length were evaluated using a multiple regression model.

RESULTS

We determined follicular phase length for the first cycles of 201 women. Women with a history of miscarriage tended to have shorter follicular phases (2.2 days). Longer duration of oral contraceptive (OC) use and recent OC use (in the last 90 days) were both correlated with longer follicular phase. Occasional marijuana users (up to three times in the last 3 months) had a longer follicular phase than nonusers (3.5 days); the follicular phase in frequent users (more than three times) was almost 2 days longer than that of nonusers.

CONCLUSIONS

The association between marijuana use and longer follicular phase is consistent with prior rhesus monkey research that shows ovulatory delay or inhibition.

Relation of luteinizing hormone levels to body mass index in premenopausal women

OBJECTIVE

To assess the relationship between body mass index (BMI) and basal LH and the LH-FSH ratio in normally menstruating women.

DESIGN

Cross-sectional analysis.

SETTING

A teaching hospital clinic.

PATIENT(S)

Premenopausal women without cancer, not currently using oral contraceptives, selected from a familial ovarian cancer clinic or the general population.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Early follicular phase plasma LH and FSH.

RESULT(S)

Luteinizing hormone increased slightly and nonsignificantly (P = 0.44) from the first to the second quintile of BMI and decreased over all subsequent quintiles. Women in the highest quintile of BMI (> 27.1) had significantly lower LH levels than women in the lowest quintile of BMI (< or = 20.4; P = 0.003). Compared with women in the second quintile of BMI who had the highest LH levels, women in the highest quintile of BMI had LH levels that were 40% lower. The relationship between BMI and the LH-FSH ratio was similar, though not as strong.

CONCLUSION(S)

Over most of the range of BMIs observed in this study, BMI was inversely associated with LH. These results suggest that the upper limits of normal for LH may need to be shifted downward for heavier women.