Influence of preterm birth and small birth size on serum anti-Müllerian hormone levels in young adult women

Beyond defence: Immune architects of ovarian health and disease

Throughout the individual's reproductive period of life the ovary undergoes continues changes, including cyclic processes of cell death, tissue regeneration, proliferation, and vascularization. Tissue-resident leucocytes particularly macrophages, play a crucial role in shaping ovarian function and maintaining homeostasis. Macrophages crucially promote angiogenesis in the follicles and corpora lutea, thereby supporting steroidogenesis. Recent research on macrophage origins and early tissue seeding has unveiled significant insights into their role in early organogenesis, e.g. in the testis. Here, we review evidence about the prenatal ovarian seeding of leucocytes, primarily macrophages with angiogenic profiles, and its connection to gametogenesis. In the prenatal ovary, germ cells proliferate, form cysts, and undergo changes that, following waves of apoptosis, give rice to the oocytes contained in primordial follicles. These follicles constitute the ovarian reserve that lasts throughout the female's reproductive life. Simultaneously, yolk-sac-derived primitive macrophages colonizing the early ovary are gradually replaced or outnumbered by monocyte-derived fetal macrophages. However, the cues indicating how macrophage colonization and follicle assembly are related are elusive. Macrophages may contribute to organogenesis by promoting early vasculogenesis. Whether macrophages contribute to ovarian lymphangiogenesis or innervation is still unknown. Ovarian organogenesis and gametogenesis are vulnerable to prenatal insults, potentially programming dysfunction in later life, as observed in polycystic ovary syndrome. Experimental and, more sparsely, epidemiological evidence suggest that adverse stimuli during pregnancy can program defective folliculogenesis or a diminished follicle reserve in the offspring. While the ovary is highly sensitive to inflammation, the involvement of local immune responses in programming ovarian health and disease remains to be thoroughly investigated.

The correlation between menstrual characteristics and fertility in women of reproductive age: a systematic review and meta-analysis

IMPORTANCE

Menstruation serves as an indicator of women's reproductive well-being and plays a pivotal role in their fertility; nevertheless, there remains an ongoing debate regarding the epidemiological evidence linking menstrual characteristics as well as fertility.

OBJECTIVE

To explore the correlation between menstrual characteristics and fertility in women of reproductive age.

DATA SOURCES

A comprehensive literature search was conducted using PubMed, Embase, Web of Science, and Cochrane libraries to identify research articles published up until February 9, 2024.

STUDY SELECTION AND SYNTHESIS

We included all studies in which the relationship between menstrual characteristics and pregnancy rates among women of reproductive age was investigated. We excluded studies involving the administration of oral contraceptives, the application of assisted reproductive technologies, and individuals with a documented history of infertility or partners with a known history of infertility.

MAIN OUTCOME MEASURE(S)

Clinical pregnancy and miscarriage.

RESULT(S)

This meta-analysis was composed of nine studies involving a total of 399,966 women, and the evidential quality derived from these studies was deemed to be high with a low risk of bias. Compared with a normal menstrual cycle length (25-32 days), the impact of a short (<25 days) or long (>32 days) menstrual cycle on a woman's pregnancy was relatively insignificant ([odds ratio {OR}, 0.81; 95% confidence interval {CI}, 0.65-1.01; I2, 68%]; [OR, 0.89; 95% CI, 0.75-1.06; I2, 60%], respectively); however, a change in cycle length may increase the risk of miscarriage ([relative risk, 1.87; 95% CI, 1.11-3.15; I2, 0]; [relative risk, 1.66; 95% CI, 1.07, 2.57; I2, 43%], respectively). In comparison to women experiencing menarche at a typical age (12-14 years), those with a late age at menarche (>14 years) exhibited a decreased likelihood of pregnancy (OR, 0.92; 95% CI, 0.91-0.93; I2, 0%); and compared with women experiencing a normal duration of menstrual bleeding (4-7 days), those with a short duration of menstrual bleeding (<4 days) exhibited reduced fertility potential (OR, 0.86; 95% CI, 0.84-0.88; I2, 29%).

CONCLUSION(S)

Short and long menstrual cycle lengths may elevate women's susceptibility to spontaneous abortion, whereas late age at menarche as well as short duration of menstrual bleeding appear to be linked to diminished fertility among women of reproductive age.

CLINICAL TRIAL REGISTRATION

PROSPERO CRD42023487458 (9 December 2023).

Body composition in adults born preterm with very low birth weight

BACKGROUND

Studies on body composition in preterm very low birth weight (VLBW < 1500 g) survivors are inconsistent and trajectories later in life unknown. We assessed body composition and its change from young to mid-adulthood in VLBW adults.

METHODS

We studied 137 VLBW adults and 158 term-born controls from two birth cohorts in Finland and Norway at mean age 36 years. Body composition was assessed by 8-polar bioelectrical impedance. We compared results with dual-energy x-ray absorptiometry measurements at 24 years.

RESULTS

In mid-adulthood, VLBW women and men were shorter than controls. Fat percentage (mean difference in women 1.1%; 95% CI, -1.5% to 3.5%, men 0.8%; -2.0% to 3.6%) and BMI were similar. VLBW women had 2.9 (0.9 to 4.8) kg and VLBW men 5.3 (2.7 to 8.1) kg lower lean body mass than controls, mostly attributable to shorter height. Between young and mid-adulthood, both groups gained fat and lean body mass (p for interaction VLBW x age>0.3).

CONCLUSION

Compared with term-born controls, VLBW adults had similar body fat percentage but lower lean body mass, largely explained by their shorter height. This could contribute to lower insulin sensitivity and muscular fitness previously found in VLBW survivors and predispose to functional limitations with increasing age.

IMPACT

In mid-adulthood, individuals born preterm with very low birth weight had similar body fat percentage but lower lean body mass than those born at term. This was largely explained by their shorter height. First study to report longitudinal assessments of body size and composition from young to mid-adulthood in very low birth weight adults. Lower lean body mass in very low birth weight adults could contribute to lower insulin sensitivity and muscular fitness and lead to earlier functional limitations with increasing age.

Age at menarche and risk of ovarian hyperstimulation syndrome in women undergoing IVF/ICSI cycles: a retrospective cohort study

OBJECTIVES

We aimed to explore the association between age at menarche (AAM) and ovarian hyperstimulation syndrome (OHSS) in fresh in vitro fertilisation (IVF)/intracytoplasmic sperm injection (ICSI) cycles.

DESIGN

A retrospective cohort study.

SETTING

Data were collected from a large obstetrics and gynaecology hospital in Sichuan, China.

PARTICIPANTS

This study included 17 419 eligible women aged ≤40 years who underwent the first IVF/ICSI cycles from January 2015 to December 2021. Women were divided into three groups according to their AAM: ≤12 years (n=5781), 13-14 years (n=9469) and ≥15 years (n=2169).

RESULTS

The means of age at recruitment and AAM were 30.4 years and 13.1 years, respectively. Restricted cubic spline models suggested that early menarche age increased the risk of OHSS. The multivariable logistic analysis showed that women with menarche age ≤12 years were more likely to suffer from OHSS (OR 1.321, 95% CI 1.113 to 1.567) compared with those aged 13-14 years among the whole cohort. This significant relationship remained in women administered with different ovarian stimulation protocols and gonadotrophin doses. When stratified by female age, this correlation was presented only in patients aged ≤30 years (OR 1.362, 95% CI 1.094 to 1.694). And the mediation analysis showed that the relationship between AAM and OHSS was totally mediated by antral follicle counts (AFC).

CONCLUSION

Menarche age earlier than 12 years may increase the OHSS risk in women aged ≤30 years through the mediation of AFC. More prospective studies are required to verify the results.

International Consensus Guideline on Small for Gestational Age (SGA): Etiology and Management from Infancy to Early Adulthood

This International Consensus Guideline was developed by experts in the field of SGA of 10 pediatric endocrine societies worldwide. A consensus meeting was held and 1300 articles formed the basis for discussions. All experts voted about the strengths of the recommendations. The guideline gives new and clinically relevant insights into the etiology of short stature after SGA birth, including novel knowledge about (epi)genetic causes. Besides, it presents long-term consequences of SGA birth and new treatment options, including treatment with gonadotropin-releasing hormone agonist (GnRHa) in addition to growth hormone (GH) treatment, and the metabolic and cardiovascular health of young adults born SGA after cessation of childhood-GH-treatment in comparison with appropriate control groups. To diagnose SGA, accurate anthropometry and use of national growth charts are recommended. Follow-up in early life is warranted and neurodevelopment evaluation in those at risk. Excessive postnatal weight gain should be avoided, as this is associated with an unfavorable cardio-metabolic health profile in adulthood. Children born SGA with persistent short stature < -2.5 SDS at age 2 years or < -2 SDS at age of 3-4 years, should be referred for diagnostic work-up. In case of dysmorphic features, major malformations, microcephaly, developmental delay, intellectual disability and/or signs of skeletal dysplasia, genetic testing should be considered. Treatment with 0.033-0.067 mg GH/kg/day is recommended in case of persistent short stature at age of 3-4 years. Adding GnRHa treatment could be considered when short adult height is expected at pubertal onset. All young adults born SGA require counseling to adopt a healthy lifestyle.

Is There a Relationship between Serum Anti-Mullerian Hormone Levels and Abortion Rates in Patients Who Received In vitro Fertilisation-Embryo Transfer Cycles?

Background

The studies which investigated the relationship between anti-Mullerian hormone (AMH) level and abortion rate have conflicting results.

Aims

This retrospective study aimed to evaluate the relationship between AMH levels and abortion in women who achieved pregnancy with in vitro fertilisation (IVF) treatment.

Settings and Design

This retrospective study was conducted in the Department of Gynecology and Obstetrics, Etlik Zubeyde Hanim Women's Health Training and Research Hospital, between January 2014 and January 2020.

Materials and Methods

Patients below 40 years of age who conceived after IVF-embryo transfer treatment during a 6-year period and had a serum AMH level measurement were included. The patients were divided into three groups according to the serum AMH levels as low AMH (L-AMH, ≤1.6 ng/mL), intermediate AMH (I-AMH, 1.61-5.6 ng/mL) and high AMH (H-AMH, >5.6 ng/mL). The groups were compared in terms of obstetric, treatment cycle characteristics and abortion rates.

Statistical Analysis Used

The Mann-Whitney U-test was used in comparison of non-parametric data of two groups; the Kruskal-Wallis test was used to compare the data of more than two groups. When a statistically significant difference was found in the Kruskal-Wallis test result, the groups were compared in pairs using the Mann-Whitney U-test, and the groups that made a statistical difference were determined. The Pearson's Chi-square and Fisher's exact tests were used to compare the independent categorical variables.

Results

L-AMH (n = 164), I-AMH (n = 153) and H-AMH (n = 59) groups were similar in terms of obstetric histories and number of cycles applied, with an abortion rate of 23.8%, 19.6% and 16.9%, respectively (P = 0.466). The same analyses were repeated in two subgroups under 34 years of age and above, and no difference was found in terms of miscarriage rates. The number of oocytes retrieved and the number of mature oocytes were higher in H-AMH group compared to intermediate and low groups.

Conclusion

No relationship was found between serum AMH level and abortion rate in women who achieved clinical pregnancy with IVF treatment.

The Causal Evidence of Birth Weight and Female-Related Traits and Diseases: A Two-Sample Mendelian Randomization Analysis

Objectives: A large meta-analysis indicated a more pronounced association between lower birth weight (BW) and diseases in women but less concern about the causality between BW and female-related phenotypes and diseases.

Methods: Mendelian randomization (MR) analysis was used to estimate the causal relationship between two traits or diseases using summary datasets from genome-wide association studies. Exposure instrumental variables are variants that are strongly associated with traits and are tested using four different statistical methods, including the inverse variance weighting, MR-Egger, weighted median, and weighted mode in MR analysis. Next, sensitivity analysis and horizontal pleiotropy were assessed using leave-one-out and MR-PRESSO packages.

Results: The body mass index (BMI) in adulthood was determined by BW (corrected β = 0.071, p = 3.19E-03). Lower BW could decrease the adult sex hormone-binding globulin (SHBG) level (β = −0.081, p = 2.08E-06), but it resulted in increased levels of bioavailable testosterone (bio-T) (β = 0.105, p = 1.25E-05). A potential inverse effect was observed between BW and menarche (corrected β = −0.048, p = 4.75E-03), and no causal association was confirmed between BW and the risk of endometriosis, leiomyoma, and polycystic ovary syndrome.

Conclusion: Our results suggest that BW may play an important role and demonstrates a significant direct influence on female BMI, SHBG and bio-T levels, and menarche.

Genetic Associations of Birthweight, Childhood, and Adult BMI on Testosterone Levels: A Mendelian Randomization

CONTEXT

Birthweight, childhood, and adult BMI have been indicated associated with the testosterone levels, but the current studies are plagued by significant heterogeneity, and a consensus about the role of these weight traits in testosterone levels is still debated.

OBJECTIVE

This work aims to evaluate the genetic associations of birthweight and childhood and adult body mass index (BMI) on the adult testosterone levels (bioavailable testosterone [BT], sex hormone-binding globulin [SHBG], and total testosterone [TT]) in women and men.

METHODS

Random-effect inverse-variance weighted (IVW) and 7 sensitivity analyses were performed. Data for weight traits were collected from large-scale genome-wide association studies (GWAS) ranging from 39 620 to 434 794 individuals. Summarized data for testosterone levels were obtained from a GWAS up to 230 454 individuals.

RESULTS

Higher adult BMI are significantly associated with lower BT (β = -0.13; 95% CI, -0.16 to -0.09) and TT in men (β = -0.25; 95% CI, -0.30 to -0.20). On the contrary, higher adult BMI increased the levels of BT (β = 0.23; 95% CI, 0.23 to 0.20) and TT (β = 0.04; 95% CI, 0.01 to 0.07) in women. Similar genetic associations on testosterone levels with sexual differences were observed for childhood BMI. However, higher birthweight led to lower BT levels in adult men (β = -0.08; 95% CI, -0.12 to -0.03) and women (β = -0.07; 95% CI, -0.13 to -0.02).

CONCLUSION

Our study supports that birthweight, childhood BMI, and adult BMI affect testosterone levels in men and women in adult life. The genetic associations of childhood BMI on testosterone levels are consistent with adult BMI, but not with birthweight.

Hyperandrogenism and Polycystic ovary syndrome: Effects in pregnancy and offspring development

Polycystic ovary syndrome (PCOS) is one of the major endocrine disorders affecting women of reproductive age. Its etiology remains unclear. It is suggested that environmental factors, and particularly the intrauterine environment, play key roles in PCOS development. Besides the role of androgens in PCOS pathogenesis, exposure to endocrine disruptors, as is Bisphenol A, could also contribute to its development. Although PCOS is considered one of the leading causes of ovarian infertility, many PCOS patients can get pregnant. Some of them by natural conception and others by assisted reproductive technique treatments. As hyperandrogenism (one of PCOS main features) affects ovarian and uterine functions, PCOS women, despite reaching pregnancy, could present high-risk pregnancies, including implantation failure, an increased risk of gestational diabetes, preeclampsia, and preterm birth. Moreover, hyperandrogenism may also be maintained in these women during pregnancy. Therefore, as an altered uterine milieu, including hormonal imbalance, could affect the developing organisms, monitoring these patients throughout pregnancy and their offspring development is highly relevant. The present review focuses on the impact of androgenism and PCOS on fertility issues and pregnancy-related outcomes and offspring development. The evidence suggests that the increased risk of pregnancy complications and adverse offspring outcomes of PCOS women would be due to the factors involved in the syndrome pathogenesis and the related co-morbidities. A better understanding of the involved mechanisms is still needed and could contribute to a better management of these women and their offspring. This article is categorized under: Reproductive System Diseases > Molecular and Cellular Physiology Reproductive System Diseases > Environmental Factors.

Early-life factors and adult anti-Müllerian hormone levels

AIM

This study aims to examine whether early-life factors are associated with adult ovarian reserve, measured by anti-Müllerian hormone (AMH) levels.

METHODS

The work is based on the Jerusalem Perinatal Study (JPS), an extensive birth cohort with detailed information on all pregnancies and deliveries in Jerusalem between 1974 and 1976. A subset of individuals participated in a follow-up study that took place between 2007 and 2009 in which they completed questionnaires and were physically examined at mean age of 32. A blood sample was additionally drawn from each participant, and AMH was measured in a sample of 239 women. The associations between each early-life factors, including birth weight, maternal pre-pregnancy weight, gestational weight gain (GWG), socioeconomic position at birth, and parental smoking during pregnancy, were assessed with AMH levels at the age of 32.Multivariable regression models were used to examine the associations with AMH, adjusting for potential confounders at birth and at the age of 32.

RESULTS

Low birth weight was significantly associated with lower ovarian reserve reflected by lower levels of AMH at age 32 (range 30-36), independent of other early-life factors and after adjusting for confounders (β = 0.180, p = 0.03).

CONCLUSIONS

This prospective study demonstrates the association of birth weight and adult ovarian reserve. Underlying mechanisms are yet to be fully understood.

Breast Cancer Risk Factors and Circulating Anti-Müllerian Hormone Concentration in Healthy Premenopausal Women

CONTEXT

We previously reported that anti-Müllerian hormone (AMH), a marker of ovarian reserve, is positively associated with breast cancer risk, consistent with other studies.

OBJECTIVE

This study assessed whether risk factors for breast cancer are correlates of AMH concentration.

METHODS

This cross-sectional study included 3831 healthy premenopausal women (aged 21-57, 87% aged 35-49) from 10 cohort studies among the general population.

RESULTS

Adjusting for age and cohort, AMH positively associated with age at menarche (P < 0.0001) and parity (P = 0.0008) and inversely associated with hysterectomy/partial oophorectomy (P = 0.0008). Compared with women of normal weight, AMH was lower (relative geometric mean difference 27%, P < 0.0001) among women who were obese. Current oral contraceptive (OC) use and current/former smoking were associated with lower AMH concentration than never use (40% and 12% lower, respectively, P < 0.0001). We observed higher AMH concentrations among women who had had a benign breast biopsy (15% higher, P = 0.03), a surrogate for benign breast disease, an association that has not been reported. In analyses stratified by age (<40 vs ≥40), associations of AMH with body mass index and OCs were similar in younger and older women, while associations with the other factors (menarche, parity, hysterectomy/partial oophorectomy, smoking, and benign breast biopsy) were limited to women ≥40 (P-interaction < 0.05).

CONCLUSION

This is the largest study of AMH and breast cancer risk factors among women from the general population (not presenting with infertility), and it suggests that most associations are limited to women over 40, who are approaching menopause and whose AMH concentration is declining.

Anti-Mullerian Hormone and Macrophage Migration Inhibitory Factor Determine the Reproductive Health of Ladakhi Women Residing at 3,500 m

Shaw, Snigdha, Himashree Gidugu, Gopinath Bhaumik, Maramreddy Prasanna Kumar Reddy, Usha Panjwani, and Dishari Ghosh. Anti-Mullerian hormone and macrophage migration inhibitory factor determine the reproductive health of Ladakhi women residing at 3,500 m. High Alt Med Biol. 00:000-000, 2021. Background: Reproductive health of Ladakhi high-altitude (HA) native females was investigated for the first time in this study. Available literature suggest that, female reproductive cycle and hormonal profile varies in different HA populations due to heterogeneity. Although these studies illustrate some progress on the role of HA hypoxia, it still leaves scope for evaluation of the remaining mechanisms involved in the maintenance of reproductive health in this contemporary population. Materials and Methods: Menstrual details, phasic variations in circulatory steroid hormones, and gonadotropins along with oxytocin in sea level (SL) and HA (∼3,500 m) native females of India were assessed. Moreover, ovarian reserve marker anti-Mullerian hormone (AMH) and proinflammatory cytokine macrophage migration inhibitory factor (MIF) were measured. Results: A difference in Ladakhi women was registered compared to SL, regarding luteinizing hormone (LH) (2.6 mIU/ml vs. 4.4 mIU/ml, p < 0.05) and progesterone (P) (4.1 ng/ml vs. 9.4 ng/ml, p < 0.05) levels in their luteal phase. Reduced LH might contribute to poor development of the ovarian corpus luteum, subsequently diminish P level. Decreased AMH level in three age groups: 21-30 years (1.4 ng/ml vs. 3.2 ng/ml, p < 0.01), 31-40 years (0.6 ng/ml vs. 2.1 ng/ml, p < 0.01), and >40 years (0.4 ng/ml vs. 1.7 ng/ml, p < 0.01) of Ladakhi women were recorded than their SL counterpart. Elevated oxytocin (83.5 ng/ml vs. 76.3 ng/ml, p < 0.05) and MIF levels (70.2 ng/ml vs. 49.7 ng/ml, p < 0.01) along with low P and AMH levels delineated the reason for recorded early menopause (43.9 years), shorter reproductive span (∼29 years), and history of miscarriage in HA dwellers compared to SL. Conclusion: Therefore, the findings insinuated that the response of the reproductive system to hypoxia in Ladakhi women differs from SL women, and the adaptive response in these women might be in favor of their reproductive health.

The anti-Mullerian hormone as a predictor of early pregnancy loss in subfertile women

The aim of this study was to evaluate the predictive value of the anti-Mullerian hormone (AMH) level for early pregnancy loss and to compare the significance of AMH level to age as prognostic factors of pregnancy loss in subfertile women. The outcome of 848 subfertile patients confirmed with intrauterine pregnancies by ultrasound within 1 year of measuring serum AMH level were retrospectively analyzed. Among 848 patients, 206 women were diagnosed with early pregnancy loss. The mean age of the 848 patients was 35.66 ± 3.61 years (range: 26-46 years), and the mean AMH level was 2.95 ± 1.89 (range: 0.14-8.82 ng/mL). There were no significant differences in gravidity, parity, body mass index (BMI), and previous abortion history depending on early pregnancy loss. However, multivariable logistic regression analysis confirmed that the probability of early pregnancy loss is significantly affected by age (odd ratio, 1.079: 1.025-1.135, P = 0.004) and AMH (odd ratio, 0.885: 0.797-0.982, p = 0.022). According to this study, AMH level and age are both powerful predictors of early pregnancy loss. While chronological age is already well known as a factor related to early pregnancy loss, AMH was also considered when individualizing risk prediction for early pregnancy loss.

What is the evidence for beneficial effects of growth hormone treatment beyond height in short children born small for gestational age? A review of published literature

Background An increasing body of evidence supports the view that both an adverse intrauterine milieu and rapid postnatal weight gain in children born small for gestational age (SGA) contribute towards the risk for the development of chronic diseases in adult life. Content The aim of this review was to identify and summarize the published evidence on metabolic and cardiovascular risk, as well as risk of impaired cardiac function, intellectual capacity, quality of life, pubertal development and bone strength among children born SGA. The review will then address whether growth hormone (GH) therapy, commonly prescribed to reduce the height deficit in children born SGA who do not catch up in height, increases or decreases these risks over time. Summary Overall, there are limited data in support of a modest beneficial effect of GH therapy on the adverse metabolic and cardiovascular risk observed in short children born SGA. Evidence to support a positive effect of GH on bone strength and psychosocial outcomes is less convincing. Outlook Further evaluation into the clinical relevance of any potential long-term benefits of GH therapy on metabolic and cardiovascular endpoints is warranted.

Serum Anti-Müllerian Hormone in the Diagnosis of Polycystic Ovary Syndrome in Association with Clinical Symptoms

Polycystic ovary syndrome (PCOS) is one of the most prevalent endocrine diseases affecting women of reproductive age. The pathogeny of PCOS is still not completely understood, but one contributing factor that has been proposed is anti-Müllerian hormone (AMH). There is currently no clear correlation between levels of AMH and incidence of PCOS in Saudi Arabian patients. The goal of this study was to determine the threshold of AMH and correlate it with PCOS clinical features to facilitate a proper diagnosis for PCOS. In this case-control study, we recruited 79 PCOS women and 69 normal ovulatory women; PCOS patients were diagnosed according to the Rotterdam criterion. On days 2–4 of the menstrual cycle, transvaginal/abdominal ultrasound was performed and serum levels of AMH, luteinizing hormone (LH), and follicle-stimulating hormone (FSH) were measured for all participants. The receiver operating characteristic curve (ROC) was used to determine the AMH diagnostic cut-off at 3.19 ng/mL, with 72% sensitivity and 70% specificity; AMH > 3.19 ng/mL was significantly correlated with PCOS. High AMH levels were correlated with age at menarche, polycystic ovarian morphology (PCOM), and oligo/amenorrhea. Serum AMH is a promising diagnostic marker of ovarian dysfunction in PCOS patients especially in cases in which the evaluation of PCOM was complicated.

Preterm Birth as a Risk Factor for Metabolic Syndrome and Cardiovascular Disease in Adult Life: A Systematic Review and Meta-Analysis

OBJECTIVE

To determine if preterm birth is associated with components of the metabolic syndrome in adult life.

STUDY DESIGN

A structured literature search was performed using PubMed. All comparative studies reported metabolic and cardiovascular outcomes in adults (≥18 years of age) born preterm (<37 weeks of gestation) compared with adults born at term (37-42 weeks of gestation) and published through March 2018 were included. The major outcomes assessed were body mass index, waist circumference, waist-to-hip ratio, fat mass, systolic blood pressure (SBP), diastolic blood pressure (DBP), 24-hour SBP, 24-hour DBP, endothelium-dependent brachial artery flow-mediated dilation, carotid intima-media thickness, pulse wave velocity, fasting glucose and insulin, Homeostasis Model Assessment-Estimated Insulin Resistance Index, and lipid profiles. Quality appraisal was performed using a modified version of the Newcastle-Ottawa scale. A meta-analysis was performed for comparable studies which reported sufficient data.

RESULTS

Forty-three studies were included, including a combined total of 18 295 preterm and 294 063 term-born adults. Prematurity was associated with significantly higher fat mass (P = .03), SBP (P < .0001), DBP (P < .0001), 24-hour SBP (P < .001), and 24-hour DBP (P < .001). Furthermore, preterm-born adults presented higher values of fasting glucose (P = .01), insulin (P = .002), Homeostasis Model Assessment-Estimated Insulin Resistance Index (P = .05), and total cholesterol levels (P = .05) in comparison with adults born at term, in random effect models. No statistically significant difference was found between preterm and term-born adults for the other outcomes studied.

CONCLUSIONS

Preterm birth is strongly associated with a number of components of the metabolic syndrome and cardiovascular disease in adult life.

IUGR: Genetic influences, metabolic problems, environmental associations/triggers, current and future management

The children with intrauterine growth restriction (IUGR) especially if they make a catch-up growth in early life have a higher risk for long term problems including short stature and also developing metabolic syndrome, Type 2 diabetes, insulin resistance and cardiovascular diseases. The studies also support that these children may have abnormalities in pubertal timing, adrenarche and reproductive function. The aim of this review was to summarize the published reports mainly on puberty and reproductive functions in children born IUGR at older ages in association with metabolic problems that they encounter. Possible mechanisms explaining these outcomes are discussed. Lastly strategies that may be taken for the prevention of IUGR related morbidities at later life are shortly presented.

Association of birth weight with functional ovarian reserve during menacme estimated by serum concentration of anti-Müllerian hormone

To investigate the relationship of birth weight (BW) of females born at full term with functional ovarian reserve (FOR) during menacme, based on serum level of anti-Müllerian hormone (AMH), among women who were 34–35 years old. This prospective birth cohort study assessed all women who were born in Ribeirão Preto City, State of São Paulo (Brazil) between June 1, 1978 and May 31, 1979. The primary endpoint was serum AMH, a marker of FOR, and its correlation with the BW of females classified as small for gestational age (SGA), appropriate for gestational age (AGA), and large for gestational (LGA). We included 274 women in this study, 19 were SGA, 238 were AGA, and 17 were LGA. The average of AMH concentration was not significantly different (p = 0.11) among women in the SGA group (2.14 ng/mL), AGA group (2.13 ng/mL), and LGA group (2.57 ng/mL). An analysis of variance indicated that the three groups also had no significant differences in the percentage of women who had adequate AMH levels (1 ng/mL; p = 0.11). There were no significant differences in the serum concentrations of AMH among 34 and 35 year-old women who were born at full term and classified as SGA, AGA, and LGA. Our sample size allowed detection of major differences between these groups (effect size of 0.8). Association of birth weight of females born at full term with functional ovarian reserve during menacme estimated by serum concentration of anti-Müllerian hormone.

Women born with very low birth weight have similar menstrual cycle pattern, pregnancy rates and hormone profiles compared with women born at term

BACKGROUND

Individuals born very preterm or with very low birth weight (VLBW) have a reduced likelihood to reproduce according to population-based register studies. Extremely low-birth weight born adults had a lower reproduction rate for both men and women in a follow-up study.

AIM

To investigate if being born with VLBW is associated with differences in the reproductive health, i.e. age of menarche, menstrual cycle pattern, pregnancy rates and hormone profile compared with women born at term.

METHODS

A prospective long-term follow-up of a cohort of live-born VLBW children and their controls studied repeatedly since birth and now assessed at 26-28 years of age. Of the totally 80 girls enrolled from birth 49 women (24 VLBW women and 25 controls) participated in the current follow-up. The women's anthropometric data and serum hormone levels were analysed.

RESULTS

The reproductive hormone levels, including Anti-Mullerian Hormone, did not differ significantly between VLBW women and their controls. Both groups reported menstrual cycle irregularities and pregnancies to the same extent but the VLBW women reported 1.5 years later age of menarche. The VLBW subjects had a catch-up growth within 18 months of birth but remained on average 5 cm shorter in adult height. There were no significant differences in BMI, sagittal abdominal diameter, blood pressure or in their answers regarding life style between the VLBW women and the controls.

CONCLUSION

No differences in the reproductive hormone levels were found between VLBW women and their controls. Although age at menarche was somewhat higher in the VLBW group menstrual cycles and pregnancy rates were similar in the VLBW and control groups. Further follow-up studies are required to elucidate the health outcomes of being born VLBW.

Intrauterine, Infant, and Childhood Factors and Ovarian Reserve in Young African American Women

Background: Ovarian toxic exposures during early development may contribute to reduced ovarian reserve in adulthood. Materials and Methods: We explored a range of intrauterine, infant, and childhood factors in relation to a biomarker of ovarian reserve, anti-Müllerian hormone (AMH) concentrations, in adulthood. We conducted a cross-sectional exploratory study of 1600 African American women 23-35 years of age residing in the Detroit, Michigan metropolitan area, who had serum AMH measurements (Ansh Labs PicoAMH enzyme-linked immunosorbent assay) and no previous polycystic ovarian syndrome diagnosis. Information on 32 intrauterine, infant, and childhood factors was ascertained by self-administered questionnaires, with 87% of participants receiving assistance from mothers. The percent differences in AMH concentrations in relation to early-life factors and 95% confidence intervals (CIs) were estimated using multivariable linear regression, adjusting for age, current hormonal contraceptive use, and body mass index. Results: Of the early-life factors evaluated in this study, two maternal pregnancy factors were associated with lower AMH concentrations in adult participants. Participants whose mothers lived or worked on a farm (vs. neither lived nor worked on a farm) when pregnant with the participant had 42% lower AMH concentrations (95% CI = -62 to -9). Among participants whose mothers lived in Michigan when pregnant with the participant (n = 1238), maternal residence in Detroit for at least a month was associated with 22% lower AMH concentrations (95% CI = -34 to -8) in the participant. Conclusions: Further research is merited to replicate our findings and identify the aspects of maternal farm exposure and Detroit residence that may be associated with lower AMH concentrations.

Children Born Small for Gestational Age: Differential Diagnosis, Molecular Genetic Evaluation, and Implications

Children born small for gestational age (SGA), defined as a birth weight and/or length below -2 SD score (SDS), comprise a heterogeneous group. The causes of SGA are multifactorial and include maternal lifestyle and obstetric factors, placental dysfunction, and numerous fetal (epi)genetic abnormalities. Short-term consequences of SGA include increased risks of hypothermia, polycythemia, and hypoglycemia. Although most SGA infants show catch-up growth by 2 years of age, ∼10% remain short. Short children born SGA are amenable to GH treatment, which increases their adult height by on average 1.25 SD. Add-on treatment with a gonadotropin-releasing hormone agonist may be considered in early pubertal children with an expected adult height below -2.5 SDS. A small birth size increases the risk of later neurodevelopmental problems and cardiometabolic diseases. GH treatment does not pose an additional risk.

Variation in levels of AMH among Maya and non-Maya women in Campeche, Mexico

OBJECTIVES

The purpose of this study was to examine anti-Müllerian hormone (AMH) levels among women of Maya and non-Maya ancestry in the city of Campeche, Mexico. Levels of AMH can potentially predict age at menopause. Previous studies have indicated an early mean age at menopause among the Maya.

MATERIALS AND METHODS

Women aged 40-60 (n = 97) participated in semistructured interviews, anthropometric measures, and blood samples. Maya/non-Maya ethnicity was determined by the last names, languages spoken, and birthplace of the woman, her parents, and her grandparents. AMH values were categorized as detectable (0.05-4.19 ng/mL) and undetectable (<0.05 ng/mL). Logistic regressions calculated odds ratios (OR) for undetectable AMH.

RESULTS

Women were categorized as Maya (n = 44), not Maya (n = 39), or not able to be clearly defined (n = 14). In bivariate comparisons, women with detectable levels of AMH were younger, more likely to be pre-menopausal, and not Maya. Age, menopausal status, and ethnicity remained significant in a logistic regression models after controlling for age at menarche. Maya women were more than five times as likely to have nondetectable AMH levels as non-Maya women.

DISCUSSION

Increasing age and progression through the menopausal transition were both associated with declining levels of AMH. The association between Maya ethnicity and a lower likelihood of detecting AMH is consistent with the early ages at menopause reported in previous studies. We considered a rapid life history model as an explanatory framework, and suggest, from an ecological perspective, that future research should consider measures of developmental stress that may compromise ovarian reserves.

Demographic, lifestyle, and other factors in relation to antimüllerian hormone levels in mostly late premenopausal women

OBJECTIVE

To identify reproductive, lifestyle, hormonal, and other correlates of circulating antimüllerian hormone (AMH) concentrations in mostly late premenopausal women.

DESIGN

Cross-sectional study.

SETTING

Not applicable.

PATIENT(S)

A total of 671 premenopausal women not known to have cancer.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Concentrations of AMH were measured in a single laboratory using the picoAMH ELISA. Multivariable-adjusted median (and interquartile range) AMH concentrations were calculated using quantile regression for several potential correlates.

RESULT(S)

Older women had significantly lower AMH concentrations (≥40 [n = 444] vs. <35 years [n = 64], multivariable-adjusted median 0.73 ng/mL vs. 2.52 ng/mL). Concentrations of AMH were also significantly lower among women with earlier age at menarche (<12 [n = 96] vs. ≥14 years [n = 200]: 0.90 ng/mL vs. 1.12 ng/mL) and among current users of oral contraceptives (n = 27) compared with never or former users (n = 468) (0.36 ng/mL vs. 1.15 ng/mL). Race, body mass index, education, height, smoking status, parity, and menstrual cycle phase were not significantly associated with AMH concentrations. There were no significant associations between AMH concentrations and androgen or sex hormone-binding globulin concentrations or with factors related to blood collection (e.g., sample type, time, season, and year of blood collection).

CONCLUSION(S)

Among premenopausal women, lower AMH concentrations are associated with older age, a younger age at menarche, and currently using oral contraceptives, suggesting these factors are related to a lower number or decreased secretory activity of ovarian follicles.

The influence of age at menarche, menstrual cycle length and bleeding duration on time to pregnancy: a large prospective cohort study among rural Chinese women

OBJECTIVE

To investigate the relations among age at menarche (AAM), menstrual cycle length, menstrual bleeding duration and time to pregnancy in a large cohort of rural Chinese women.

DESIGN

A prospective cohort study.

SETTING

Local family-planning service agencies and maternal/child care service centres.

POPULATION

A total of 391 320 rural women of reproductive age who participated in the National Free Pre-pregnancy Checkups and were planning to conceive were enrolled.

METHODS

Menstrual characteristics were collected via face-to-face interviews. The Cox proportional hazards model were used to estimate the fecundability ratios (FRs) and 95% confidence intervals for each measure relative to its reference category.

MAIN OUTCOME MEASURES

Time to pregnancy.

RESULTS

Women with an AAM later than 14 years of age were less likely become pregnant compared with women with AAM at 13-14 years of age (FR 0.93, 95% CI 0.92-0.94). Those with menstrual cycle lengths >29 days were less likely to come pregnant (FR 0.91, 95% CI 0.90-0.92) compared with the reference cycle length of 27-29 days. Women with bleeding durations of <4 (FR 0.88; 95% CI 0.86-0.91) or >5 days (FR 0.91; 95% CI 0.90-0.91) showed lower FRs compared with those reporting 4-5 days of bleeding. The associations were independent of maternal age, ethnicity, education level, occupation, tobacco use, alcohol use and body mass index.

CONCLUSION

A later onset of menarche, longer menstrual cycle length, both shorter (<4 days) and longer (>5 days) bleeding duration were associated with a lower FR and longer time to pregnancy in rural Chinese women.

TWEETABLE ABSTRACT

A later menarche, longer cycle, shorter or longer bleeding duration were associated with lower fecundity.

Antimüllerian hormone in relation to tobacco and marijuana use and sources of indoor heating/cooking

OBJECTIVE

To evaluate exposure to tobacco, marijuana, and indoor heating/cooking sources in relation to antimüllerian hormone (AMH) levels.

DESIGN

Cross-sectional analysis in a sample of premenopausal women (n = 913) enrolled in the Sister Study cohort (n = 50,884).

SETTING

Not applicable.

PATIENT(S)

Women, ages 35-54 years at time of enrollment, with an archived serum sample and at least one intact ovary and classified as premenopausal.

INTERVENTION(S)

Not applicable.

MAIN OUTCOME MEASURE(S)

Serum AMH (ng/mL) levels ascertained by ultrasensitive ELISA assay.

RESULT(S)

Lower AMH levels were associated with sources of indoor heating, including burning wood (-36.0%; 95% confidence interval [CI], -55.7%, -7.8%) or artificial fire logs (-45.8%; 95% CI, -67.2%, -10.4%) at least 10 times/year in a residential indoor stove/fireplace. Lower AMH levels were also observed in women who were current smokers of ≥20 cigarettes/day relative to nonsmokers (-56.2%; 95% CI, -80.3%, -2.8%) and in women with 10+ years of adult environmental tobacco smoke (ETS) exposure (-31.3%; 95% CI, -51.3%, -3.1%), but no associations were observed for marijuana use.

CONCLUSION(S)

We confirmed previously reported findings of lower AMH levels in current heavy smokers and also found associations for long-term ETS exposure and indoor burning of wood or artificial fire logs. These findings suggest that combustion by-products from common exposures can have toxic effects on the human ovary.

Maternal cigarette smoking during pregnancy and reproductive health in children: a review of epidemiological studies

Maternal cigarette smoking may affect the intrauterine hormonal environment during pregnancy and this early fetal exposure may have detrimental effects on the future trajectory of reproductive health. In this review, we discuss the epidemiological literature on the association between prenatal exposure to maternal cigarette smoking and several aspects of reproductive health. The literature points towards an increased risk of the urogenital malformation cryptorchidism, but a potential protective effect on the risk of hypospadias in sons following prenatal cigarette smoking exposure. Studies on sexual maturation find a tendency towards accelerated pubertal development in exposed boys and girls. In adult life, prenatally exposed men have impaired semen quality compared with unexposed individuals, but an influence on fecundability, that is, the biological ability to reproduce, is less evident. We found no evidence to support an association between prenatal cigarette smoking exposure and testicular cancer. Among adult daughters, research is sparse and inconsistent, but exposure to cigarette smoking in utero may decrease fecundability. In conclusion, prenatal exposure to cigarette smoking may cause some long-term adverse effects on the reproductive health.

Intrauterine factors and risk of nonepithelial ovarian cancers

OBJECTIVE

The majority of ovarian tumors in girls and young women are nonepithelial in origin. The etiology of nonepithelial ovarian tumors remains largely unknown, and intrauterine exposures may play an important role. We examined the association of perinatal factors with risk of nonepithelial ovarian tumors in girls and young women.

METHODS

National cohort study of 1,536,057 women born in Sweden during 1973-2004 and followed for diagnoses of nonepithelial ovarian tumors through 2009 (attained ages 5-37 years). Perinatal and maternal characteristics and cancer diagnoses were ascertained using nationwide health registry data.

RESULTS

147 women were diagnosed with nonepithelial ovarian tumors in 31.6 million person-years of follow-up, including 94 with germ cell tumors and 53 with sex-cord stromal tumors. Women born preterm (<37 weeks of gestation) had a significantly increased risk of developing nonepithelial ovarian tumors (adjusted hazard ratio 1.86, 95% CI 1.03-3.37; p=0.04). Histological subgroup analyses showed that preterm birth was associated with increased risk of sex-cord stromal tumors (4.39, 2.12-9.10; p<0.001), but not germ cell tumors (0.68, 0.21-2.15; p=0.51). No significant associations were found with fetal growth, birth order, and maternal age at birth.

CONCLUSIONS

This large cohort study provides the first evidence that preterm birth is a risk factor for developing sex cord-stromal tumors. Ovarian hyperstimulation in response to high gonadotropin levels in preterm girls could mediate disease risk through the proliferative and steroidogenic effects of FSH and LH on granulosa and theca cells, from which most sex-cord stromal tumors are derived.

Prenatal exposures and anti-Mullerian hormone in female adolescents: the Avon Longitudinal Study of Parents and Children

Given that the primordial ovarian follicular pool is established in utero, it may be influenced by parental characteristics and the intrauterine environment. Anti-Müllerian hormone (AMH) levels are increasingly recognized as a biomarker of ovarian reserve in females in adulthood and adolescence. We examined and compared associations of maternal and paternal prenatal exposures with AMH levels in adolescent (mean age, 15.4 years) female offspring (n = 1,399) using data from the Avon Longitudinal Study of Parents and Children, a United Kingdom birth cohort study that originated in 1991 and is still ongoing (data are from 1991–2008). The median AMH level was 3.67 ng/mL (interquartile range: 2.46–5.57). Paternal but not maternal smoking prior to and during pregnancy were inversely associated with AMH levels. No or irregular maternal menstrual cycles before pregnancy were associated with higher AMH levels in daughter during adolescence. High maternal gestational weight gain (top fifth versus the rest of the distribution) was associated with lower AMH levels in daughters. Parental age, body mass index, and alcohol intake during pregnancy, child's birth weight, and maternal parity and time to conception were not associated with daughters' AMH levels. Our results suggest that some parental preconceptual characteristics and environmental exposures while the child is in utero may influence the long-term ovarian development and function in female offspring.

Anti-müllerian hormone is not associated with cardiometabolic risk factors in adolescent females

OBJECTIVES

Epidemiological evidence for associations of Anti-Müllerian hormone (AMH) with cardiometabolic risk factors is lacking. Existing evidence comes from small studies in select adult populations, and findings are conflicting. We aimed to assess whether AMH is associated with cardiometabolic risk factors in a general population of adolescent females.

METHODS

AMH, fasting insulin, glucose, HDLc, LDLc, triglycerides and C-reactive protein (CRP) were measured at a mean age 15.5 years in 1,308 female participants in the Avon Longitudinal Study of Parents and Children (ALSPAC). Multivariable linear regression was used to examine associations of AMH with these cardiometabolic outcomes.

RESULTS

AMH values ranged from 0.16-35.84 ng/ml and median AMH was 3.57 ng/ml (IQR: 2.41, 5.49). For females classified as post-pubertal (n = 848) at the time of assessment median (IQR) AMH was 3.81 ng/ml (2.55, 5.82) compared with 3.25 ng/ml (2.23, 5.05) in those classed as early pubertal (n = 460, P≤0.001). After adjusting for birth weight, gestational age, pubertal stage, age, ethnicity, socioeconomic position, adiposity and use of hormonal contraceptives, there were no associations with any of the cardiometabolic outcomes. For example fasting insulin changed by 0% per doubling of AMH (95%CI: -3%,+2%) p  = 0.70, with identical results if HOMA-IR was used. Results were similar after additional adjustment for smoking, physical activity and age at menarche, after exclusion of 3% of females with the highest AMH values, after excluding those that had not started menarche and after excluding those using hormonal contraceptives.

CONCLUSION

Our results suggest that in healthy adolescent females, AMH is not associated with cardiometabolic risk factors.

Does hormonal contraception prior to in vitro fertilization (IVF) negatively affect oocyte yields? A pilot study

BACKGROUND

As oral contraceptives (OCs) suppress anti-Müllerian hormone (AMH), and hormonal contraceptives (HCs), likely, suppress functional ovarian reserve, this study was initiated to determine whether HC affect oocyte yields.

METHODS

We investigated in a retrospective cohort study 43 oocyte donors in 71 in vitro fertilization (IVF) cycles, evaluating anti-Müllerian hormone (AMH) and oocyte yields as reflections of functional ovarian reserve (OR). In 25 IVF cycles egg donors were on HC within one month prior to IVF, and in 46 cycles they were not. Donors, based on their HCs, were further subdivided into 12 with less, and 13 with more androgenic progestins.

RESULTS

While the three groups did not differ in age, age at menarche, BMI and AMH, oocyte yields among donors who utilized estrane- and gonane-derived (higher androgenic) HCs were lower 11.3 (95% CI 8.3 - 14.3) than either donors using no HCs 16.6 (95% CI 14.7 -18.4) (P < 0.05) or those using anti-androgenic HCs 19.0 (95% CI 12.2-25.8) (P< 0.01). Significance was maintained after adjustments for the donor age and total FSH dose used in ovulation induction.

CONCLUSIONS

Even in young oocyte donors, high androgenic OC exposure appears to suppress functional ovarian reserve and oocyte yields. Since OCs are often routinely used in preparation for IVF, such practice may require reevaluation. Especially in women with diminished ovarian reserve OCs, and especially high androgenic progestin HCs, should, likely, be avoided.

Preterm birth and the metabolic syndrome in adult life: a systematic review and meta-analysis

BACKGROUND

Preterm birth is associated with features of the metabolic syndrome in later life. We performed a systematic review and meta-analysis of studies reporting markers of the metabolic syndrome in adults born preterm.

METHODS

Reports of metabolic syndrome-associated features in adults (≥18 years of age) born at <37-week gestational age and at term (37- to 42-week gestational age) were included. Outcomes assessed were BMI, waist-hip ratio, percentage fat mass, systolic (SBP) and diastolic (DBP) blood pressure, 24-hour ambulatory SBP and DBP, flow-mediated dilatation, intima-media thickness, and fasting glucose, insulin, and lipid profiles.

RESULTS

Twenty-seven studies, comprising a combined total of 17,030 preterm and 295,261 term-born adults, were included. In adults, preterm birth was associated with significantly higher SBP (mean difference, 4.2 mm Hg; 95% confidence interval [CI], 2.8 to 5.7; P < .001), DBP (mean difference, 2.6 mm Hg; 95% CI, 1.2 to 4.0; P < .001), 24-hour ambulatory SBP (mean difference, 3.1 mm Hg; 95% CI, 0.3 to 6.0; P = .03), and low-density lipoprotein (mean difference, 0.14 mmol/L; 95% CI, 0.05 to 0.21; P = .01). The preterm-term differences for women was greater than the preterm-term difference in men by 2.9 mm Hg for SBP (95% CI [1.1 to 4.6], P = .004) and 1.6 mm Hg for DBP (95% CI [0.3 to 2.9], P = .02).

CONCLUSIONS

For the majority of outcome measures associated with the metabolic syndrome, we found no difference between preterm and term-born adults. Increased plasma low-density lipoprotein in young adults born preterm may represent a greater risk for atherosclerosis and cardiovascular disease in later life. Preterm birth is associated with higher blood pressure in adult life, with women appearing to be at greater risk than men.

Peripubertal changes in circulating antimüllerian hormone levels in girls

Objective

To identify correlates and longitudinal changes in circulating antimüllerian hormone (AMH) levels as a marker of ovarian primordial follicle recruitment in normal peripubertal girls.

Design

Observational study using mixed longitudinal and cross-sectional analyses.

Setting

Not applicable.

Patient(s)

Unselected girls assessed at ages 7–11 years.

Intervention(s)

None.

Main Outcome Measure(s)

AMH, inhibin B, and FSH levels were analyzed in blood samples collected at ages 7, 9, and 11 years for longitudinal analyses and at age 8 years for cross-sectional analyses.

Result(s)

In the cross-sectional analysis, AMH levels at age 8 years were lower in pubertal girls (median 25.0 pmol/L, interquartile range [IQR] 16.0–33.9; n = 39) than in prepubertal girls (33.5 pmol/L, IQR 22.3–49.1; n = 342). In prepubertal girls, higher AMH levels were associated with higher inhibin B levels, lower FSH levels, and larger body mass index at age 8 years and subsequently with later age at menarche. AMH levels were unrelated to birth weight or birth length. In the longitudinal analysis, AMH levels increased between ages 7 (median 27.0 pmol/L, IQR 19.2–34) and 9 years (32.0 pmol/L, IQR 26.5–42.7), then declined between 9 and 11 years (26.5 pmol/L, IQR 19–42.25) with high intraindividual correlation in AMH levels between ages 7 and 9 years and 7 and 11 years.

Conclusion(s)

Measurement of circulating AMH and inhibin B levels suggests that the rate of ovarian primordial follicle recruitment increases in the prepubertal years then declines again following the onset of puberty as follicular activity pattern changes.

Maternal smoking during pregnancy and reproductive health of daughters: a follow-up study spanning two decades

STUDY QUESTION

Does in utero exposure to constituents of cigarette smoke have a programming effect on daughters' age of menarche and markers of long-term reproductive health?

SUMMARY ANSWER

In utero exposure to constituents of cigarette smoke was associated with earlier age of menarche and--to a lesser extent--changes in the testosterone profile of the young women.

WHAT IS KNOWN ALREADY

Studies observe potential effects of in utero exposure to constituents of cigarette smoke on the intrauterine formation of female gonads, but the consequences on long-term reproductive health in daughters remain unclear.

STUDY DESIGN, SIZE AND DURATION

A prospective cohort study was designed using data from 965 pregnant women enrolled prior to a routine 30th-week antenatal examination at a midwifery practice in Denmark from 1988 to 1989 and a follow-up of their 19-21-year-old daughters in 2008.

PARTICIPANTS/MATERIALS, SETTING AND METHODS

The pregnant women provided information on lifestyle factors during pregnancy, including the exact number of cigarettes smoked per day during the first and the second trimesters. A total of 438 eligible daughters were asked to complete a web-based questionnaire on reproductive health and subsequently invited to participate in a clinical examination during 2008. Of the 367 daughters (84%) who answered the questionnaire, 267 (61%) agreed to further examination. Information on menstrual pattern was provided at examination, blood samples were drawn to be analyzed for serum levels of reproductive hormones [FSH, LH, estradiol (E(2)), sex hormone-binding globulin, anti-Müllerian hormone, dehydroepiandrosterone-sulphate (DHEAS), free testosterone and free E(2)] and number of follicles (2-9 mm) were examined by transvaginal ultrasound. The daughters were divided into three exposure groups according to the level of maternal smoking during first trimester [non-exposed (reference), low-exposed (mother smoking >0-9 cigarettes/day) and high-exposed (mother smoking ≥ 10 cigarettes/day)]. Data were analyzed by multiple regression analyses in which we adjusted for potential confounders. Both crude and adjusted test for trend were carried out using maternal smoking during the first trimester as a continuous variable.

MAIN RESULTS AND THE ROLE OF CHANCE

We observed an inverse association between in utero exposure to constituents of cigarette smoke and age of menarche (P = 0.001). Daughters exposed to >0-9 cigarettes/day debuted with -2.7 [95% confidence interval (CI) -5.2 to -0.1] percentage earlier age of menarche, whereas daughters exposed to ≥ 10 cigarettes/day had -4.1 (95% CI: -6.6 to -1.5) percentage earlier age of menarche corresponding to 6.5 (95% CI: -10.7 to -2.2) months. There was a non-significant tendency towards lower levels of testosterone and DHEAS with increasing in utero exposure to constituents of cigarette smoke but no associations with follicle number, cycle length or serum levels of the other reproductive hormones were observed.

LIMITATIONS AND REASONS FOR CAUTION

We collected information on age of menarche retrospectively but the recall time was relatively short (2-10 years) and the reported values were within the normal range of Caucasians. Analyses of reproductive hormones are presented only for the group of daughters who were non-users of hormonal contraceptives because users were excluded, leaving only a low number of daughters available for the analyses (n = 75), as reflected in the wide CIs. The analyses of hormones were further adjusted for menstrual phase at time of clinical examination (follicular, ovulation and luteal phase) because blood samples were not collected on a specific day of the menstrual cycle.

WIDER IMPLICATIONS OF THE FINDINGS

This study supports the limited evidence of an inverse association between maternal smoking during pregnancy and age of menarche and further addresses to what extent reproductive capacity and hormones may be programmed by maternal smoking during pregnancy. A trend toward earlier maturation of females is suggested to have implications on long-term reproductive function.

STUDY FUNDING/COMPETING INTEREST(S)

Supported by a scholarship from The Lundbeck Foundation (R93-A8476). No conflict of interest declared.