A Biphasic Pattern of Reproductive Hormones in Healthy Female Infants: The COPENHAGEN Minipuberty Study

Associations of pentachlorophenol exposure during pregnancy with maternal and infant reproductive hormones based on a birth cohort

Pentachlorophenol (PCP), a typical environmental endocrine disruptor and a new persistent organic pollutant, has been extensively used as a pesticide worldwide. Although its use has been restricted for decades, PCP remains prevalent in both the environment and human bodies. Despite the known endocrine-disrupting and exogenous hormonal effects of PCP, few epidemiological studies examined such impact, especially among sensitive populations and during critical periods. Based on a prospective birth cohort in Wuhan, China, we collected maternal (first trimester; 13.0 ± 1.02 gestational weeks) and infant urine samples (1.16 ± 0.22 months postpartum) from 720 mother-infant pairs. We aimed to examine the association of PCP exposure during early pregnancy with maternal and infant urinary sex steroid hormones, including estrogens (estrone, E1; estradiol, E2; estriol, E3), progestogens (progesterone, P4; pregnenolone, P5; 17α-OH-Progesterone, 17OHP4; 17α-OH-Pregnenolone, 17OHP5), and androgens (testosterone, Testo; dihydrotestosterone, DHT; dehydroepiandrosterone, DHEA; androstenedione, A4). Additionally, gonadotropins [follicle-stimulating hormone (FSH) and luteinizing hormone (LH)] were measured in infant urine. Detection frequencies of all the sex steroid hormones in the maternal urine samples (>99 %) were higher than those in the infants' [most ≥80 %, except for E1 (3.36 %) and E2 (21.4 %)]. Maternal urinary PCP concentration was found to be significantly related with increased maternal sex steroid hormone concentrations; each interquartile increase in PCP concentration was positively related with percent change of the hormones (%Δ) ranging from 26.6 % to 48.5 %. On the other hand, maternal PCP exposure was associated with significantly increased P4 in male infants [%Δ (95 % confidence interval): 10.5 (0.56, 21.4)] but slightly decreased P4 in female infants [-11.9 (-21.8, 0.68)]. In addition, maternal PCP exposure was significantly associated with decreased FSH [%Δ (95 % CI): -9.90 (-17.0, -2.18)] and LH [-8.44 (-16.0, -0.19)] in the female infants, but not in the male infants. Sensitivity analyses, excluding infertility related treatment, pregnancy complications, preterm birth, or low birth weight, showed generally consistent results. Our findings implied that maternal/prenatal PCP exposure might disrupt the homeostasis of maternal and infant reproductive hormones. However, further studies are needed to confirm the findings.

Navigating fertility dilemmas across the lifespan in girls with Turner syndrome-a scoping review

BACKGROUND

Girls with Turner syndrome (TS) lack a partial or complete sex chromosome, which causes an accelerated decline of their ovarian reserve. Girls have to deal with several dilemmas related to their fertility, while only a limited number of them are referred to a fertility specialist and counselled about options of family planning on time.

OBJECTIVE AND RATIONALE

This scoping review provides an update of the literature on fertility in girls with TS throughout their lifespan and aims to propose a clinical practice guideline on fertility in TS.

SEARCH METHODS

Databases of PubMed, Embase, and Web of science were searched using the following key terms: Turner syndrome, fertility, puberty, pregnancy, sex-hormones, karyotype, fertility preservation, assisted reproductive techniques, and counselling, alongside relevant subject headings and synonymous terms. English language articles published since 2007 were critically reviewed. Pregnancies after using donated oocytes and data about girls with TS with Y-chromosomal content were excluded.

OUTCOMES

This search identified 1269 studies of which 120 were extracted for the review. The prevalence of natural conception ranged from 15% to 48% in women with 45,X/46,XX, 1% to 3% in women with 45,X, and 4% to 9% in women with other TS karyotypes. When assessing a girl's fertility potential, it was crucial to determine the karyotype in two cell lines, because hidden mosaicism may exist. In addition to karyotype, assessment of anti-Müllerian hormone (AMH) played a significant role in estimating ovarian function. Girls with AMH above the detection limit were most likely to experience spontaneous thelarche, menarche, and ongoing ovarian function during the reproductive lifespan. Fertility preservation became more routine practice: vitrification of oocytes was reported in 58 girls with TS and a median of five oocytes were preserved per stimulation. Ovarian tissue cryopreservation has demonstrated the presence of follicles in approximately 30% of girls with TS, mostly in girls with mosaic-TS, spontaneous puberty, and AMH above the detection limit. Although girls and their parents appreciated receiving counselling on fertility in TS, only one in ten girls with TS received specialized counselling. Unfamiliarity with fertility preservation techniques or uncertainties regarding the eligibility of a girl for fertility preservation constituted barriers for healthcare professionals when discussing fertility with girls with TS.

WIDER IMPLICATIONS

There currently is a high demand for fertility preservation techniques in girls with TS. A reliable prognostic model to determine which girls with TS might benefit from fertility preservation is lacking. Only a minority of these girls received comprehensive fertility counselling on the full spectrum of fertility, including uncertainties of fertility preservation, pregnancy risks, and alternatives, such as adoption. Fertility preservation could be a viable option for girls with TS. However, the question remains whether enough oocytes can be obtained for a realistic prospect of a live birth. It is important that girls and parents are empowered with the necessary information to make a well-informed decision.

Hormone Therapy During Infancy or Early Childhood for Patients with Hypogonadotropic Hypogonadism, Klinefelter or Turner Syndrome: Has the Time Come?

Managing patients unable to produce sex steroids using gonadotropins to mimic minipuberty in hypogonadotropic hypogonadism, or sex steroids in patients with Klinefelter or Turner syndrome, is promising. There is a need to pursue research in this area, with large prospective cohorts and long-term data before these treatments can be routinely considered.

Diagnosing and treating anterior pituitary hormone deficiency in pediatric patients

Hypopituitarism, or the failure to secrete hormones produced by the anterior pituitary (adenohypophysis) and/or to release hormones from the posterior pituitary (neurohypophysis), can be congenital or acquired. When more than one pituitary hormone axis is impaired, the condition is known as combined pituitary hormone deficiency (CPHD). The deficiency may be primarily due to a hypothalamic or to a pituitary disorder, or concomitantly both, and has a negative impact on target organ function. This review focuses on the pathophysiology, diagnosis and management of anterior pituitary hormone deficiency in the pediatric age. Congenital hypopituitarism is generally due to genetic disorders and requires early medical attention. Exposure to toxicants or intrauterine infections should also be considered as potential etiologies. The molecular mechanisms underlying the fetal development of the hypothalamus and the pituitary are well characterized, and variants in the genes involved therein may explain the pathophysiology of congenital hypopituitarism: mutations in the genes expressed in the earliest stages are usually associated with syndromic forms whereas variants in genes involved in later stages of pituitary development result in non-syndromic forms with more specific hormone deficiencies. Tumors or lesions of the (peri)sellar region, cranial radiation therapy, traumatic brain injury and, more rarely, other inflammatory or infectious lesions represent the etiologies of acquired hypopituitarism. Hormone replacement is the general strategy, with critical periods of postnatal life requiring specific attention.

Normal Puberty

Puberty is characterized by gonadarche and adrenarche. Gonadarche represents the reactivation of the hypothalamic-pituitary-gonadal axis with increased gonadotropin-releasing hormone, luteinizing hormone, and follicle-stimulating hormone secretion following the quiescence during childhood. Pubarche is the development of pubic hair, axillary hair, apocrine odor reflecting the onset of pubertal adrenal maturation known as adrenarche. A detailed understanding of these pubertal processes will help clarify relationships between the timing of the onset of puberty and cardiovascular, metabolic, and reproductive outcomes in adulthood. The onset of gonadarche is influenced by neuroendocrine signals, genetic variants, metabolic factors, and environmental elements.

Primary Amenorrhea and Premature Ovarian Insufficiency

This review focuses on primary amenorrhea and primary/premature ovarian insufficiency due to hypergonadotropic hypogonadism. Following a thoughtful, thorough evaluation, a diagnosis can usually be discerned. Pubertal induction and ongoing estrogen replacement therapy are often necessary. Shared decision-making involving the patient, family, and health-care team can empower the young person and family to successfully thrive with these chronic conditions.

New liquid chromatography tandem mass spectrometry reference data for estradiol show mini-puberty in both sexes and typical pre-pubertal and pubertal patterns

CONTEXT

Reliable estradiol (E2) reference intervals (RIs) are crucial in pediatric endocrinology.

OBJECTIVES

This study aims to develop a sensitive ultra-performance liquid chromatographic tandem mass spectrometry (UPLC-MS/MS) method for E2 in serum, to establish graphically represented RI percentiles and annual RIs for both sexes, and to perform a systematic literature comparison.

METHODS

First, a UPLC-MS/MS method for E2 was developed. Second, graphically represented RI percentiles and annual RIs covering 0-18 years were computed (cohort of healthy children [1181 girls and 543 boys]). Subsequently, RIs were compared with published data by systematic searches.

RESULTS

Lower limit of quantification was 11 pmol/L, indicating high sensitivity. Estradiol first peaked during mini-puberty in both sexes (girls up to 192 pmol/L; boys up to 225 pmol/L). As could be expected, girls showed higher pubertal E2 (up to 638 pmol/L). However, boys' RIs (up to 259 pmol/L) overlapped considerably. We found 4 studies in the literature that also used LC-MS/MS to determine E2 and published RIs for the complete pediatric age range. Reference intervals varied considerably. Pre-pubertal and pubertal phases were present in all studies. Higher E2 during the time of mini-puberty in both sexes was documented in 3 studies including ours.

CONCLUSIONS

Variability of RIs for E2 between studies illustrates the importance of laboratory-specific RIs despite using a LC-MS/MS reference method. In boys, the striking E2 peak during mini-puberty as well as high pubertal E2 without phenotypic estrogenization in regular male puberty indicates that the role of E2 in children and, especially in boys, requires better functional understanding.

Cohort profile: The Copenhagen Analgesic Study-The COPANA cohort

BACKGROUND

Development of the gonads during fetal life is complex and vital for adult reproductive health. Cell and animal studies have shown an alarming effect of mild analgesics on germ cells in both males and females. More than 50% of pregnant women use mild analgesics during pregnancy, which potentially could compromise the reproductive health of the next generation.

OBJECTIVES

We present a research protocol designed to evaluate the effect of prenatal exposure to mild analgesics and endocrine-disrupting chemicals on gonadal function in the offspring.

POPULATION

Healthy, singleton pregnant women and their partners.

DESIGN

The COPANA cohort is a prospective, observational pregnancy and birth cohort.

METHODS

Participants were enrolled during the first trimester of pregnancy. Information on the use of mild analgesics was collected retrospectively 3 months prior to pregnancy and prospectively every 2 weeks throughout the study. We collected extensive data on lifestyle and reproductive health. Biospecimens were collected in the first trimester (maternal and paternal urine- and blood samples), in the third trimester in conjunction with a study-specific ultrasound scan (maternal urine sample), and approximately 3 months post-partum during the infant minipuberty period (maternal and infant urine- and blood samples). A comprehensive evaluation of reproductive function in the infants during the minipuberty phase was performed, including an ultrasound scan of the testis or ovaries and uterus.

PRELIMINARY RESULTS

In total, 685 pregnant women and their partners were included between March 2020 and January 2022. A total of 589 infants (287 males) and their parents completed the follow-up during the minipuberty phase (December 2020-November 2022).

CONCLUSIONS

The Copenhagen Analgesic Study holds the potential to provide novel and comprehensive insights into the impact of early and late prenatal exposure to mild analgesics and other endocrine-disrupting chemicals on future reproductive function in the offspring.

Enhanced identification of endocrine disruptors through integration of science-based regulatory practices and innovative methodologies: The MERLON Project

The prevalence of hormone-related health issues caused by exposure to endocrine disrupting chemicals (EDCs) is a significant, and increasing, societal challenge. Declining fertility rates together with rising incidence rates of reproductive disorders and other endocrine-related diseases underscores the urgency in taking more action. Addressing the growing threat of EDCs in our environment demands robust and reliable test methods to assess a broad variety of endpoints relevant for endocrine disruption. EDCs also require effective regulatory frameworks, especially as the current move towards greater reliance on non-animal methods in chemical testing puts to test the current paradigm for EDC identification, which requires that an adverse effect is observed in an intact organism. Although great advances have been made in the field of predictive toxicology, disruption to the endocrine system and subsequent adverse health effects may prove particularly difficult to predict without traditional animal models. The MERLON project seeks to expedite progress by integrating multispecies molecular research, new approach methodologies (NAMs), human clinical epidemiology, and systems biology to furnish mechanistic insights and explore ways forward for NAM-based identification of EDCs. The focus is on sexual development and function, from foetal sex differentiation of the reproductive system through mini-puberty and puberty to sexual maturity. The project aims are geared towards closing existing knowledge gaps in understanding the effects of EDCs on human health to ultimately support effective regulation of EDCs in the European Union and beyond.

Early Life Anti-Müllerian Hormone Trajectories in Infant Girls

BACKGROUND

Minipuberty is a period of increased reproductive axis activity in infancy, but the importance of this period is not well understood, especially in girls. Previous studies reported a peak in hormone concentrations at 3 to 4 months old. Our objective is to describe anti-Müllerian hormone (AMH) trajectories in the context of other minipuberty factors among healthy infant girls using longitudinal measures of AMH.

METHODS

The Infant Feeding and Early Development study is a longitudinal cohort study of healthy infants, recruited from hospitals in the Philadelphia area during 2010 to 2013. We measured AMH in 153 girls who contributed 1366 serum samples across 11 study visits over 36 weeks. We also measured follicle stimulating hormone (FSH), estradiol, and ovarian characteristics. We used latent class mixed effects models to cluster trajectories of AMH concentration with age. Using linear mixed models, we estimated FSH and ovarian characteristic trajectories separately by AMH cluster.

RESULTS

We classified infants into four clusters that represent patterns of AMH that were high and decreasing (decreasing), had a peak around 12 weeks or 20 weeks (early peak and middle peak), or were consistently low (low). Infants in these clusters differed in their FSH trajectories, timing of estradiol production, and ovarian characteristics.

CONCLUSIONS

The AMH clusters identified suggest variation in the timing and the magnitude of the minipuberty response in infant girls. The decreasing and low clusters have not been described previously and should be further evaluated to determine whether they represent an opportunity for the early identification of later reproductive conditions.

AMH and other markers of ovarian function in patients with Turner syndrome - a single center experience of transition from pediatric to gynecological follow up

Turner syndrome (TS) is a chromosomal disorder that affects about 1 in 2500 female births and is characterized by the partial or complete absence of the second X chromosome. Depending on karyotype, TS is associated with primary ovarian insufficiency (POI). Approximately 50% of girls with a mosaic 45, X/46, XX karyotype may enter puberty spontaneously, but only 5-10% of women with TS achieve pregnancy without egg donation. In this review, we will evaluate the clinical use of markers of ovarian function in TS patients. Based on longitudinal studies of serum concentrations of reproductive hormones as well as ovarian morphology in healthy females and patients with TS, we will evaluate how they can be applied in a clinical setting. This is important when counseling patients and their families about future ovarian function essential for pubertal development and fertility. Furthermore, we will report on 20 years of experience of transition from pediatric to gynecological and adult endocrinological care in our center at Rigshospitalet, Copenhagen, Denmark.

Organ Abnormalities Caused by Turner Syndrome

Turner syndrome (TS), a genetic disorder due to incomplete dosage compensation of X-linked genes, affects multiple organ systems, leading to hypogonadotropic hypogonadism, short stature, cardiovascular and vascular abnormalities, liver disease, renal abnormalities, brain abnormalities, and skeletal problems. Patients with TS experience premature ovarian failure with a rapid decline in ovarian function caused by germ cell depletion, and pregnancies carry a high risk of adverse maternal and fetal outcomes. Aortic abnormalities, heart defects, obesity, hypertension, and liver abnormalities, such as steatosis, steatohepatitis, biliary involvement, liver cirrhosis, and nodular regenerative hyperplasia, are commonly observed in patients with TS. The SHOX gene plays a crucial role in short stature and abnormal skeletal phenotype in patients with TS. Abnormal structure formation of the ureter and kidney is also common in patients with TS, and a non-mosaic 45,X karyotype is significantly associated with horseshoe kidneys. TS also affects brain structure and function. In this review, we explore various phenotypic and disease manifestations of TS in different organs, including the reproductive system, cardiovascular system, liver, kidneys, brain, and skeletal system.

Urinary concentration of phthalates and bisphenol A during minipuberty is associated with reproductive hormone concentrations in infant boys

BACKGROUND

The transient postnatal activation of the hypothalamic-pituitary-gonadal hormone axis is termed minipuberty and considered an important developmental period, which is highly sensitive to endocrine disruption. Here, we explore exposure-outcome associations during minipuberty between concentrations of potentially endocrine disrupting chemicals (EDCs) in urine of infant boys and their serum reproductive hormone concentrations.

METHODS

In total, 36 boys participating in the COPENHAGEN Minipuberty Study had data available for both urine biomarkers of target endocrine disrupting chemicals and reproductive hormones in serum from samples collected on the same day. Serum concentrations of reproductive hormones were measured by immunoassays or by LC-MS/MS. Urinary concentrations of metabolites of 39 non-persisting chemicals, including phthalates and phenolic compounds, were measured by LC-MS/MS. Nineteen chemicals had concentrations above the limit of detection in ≥50% of children and were included in data analysis. Associations of urinary phthalate metabolite and phenol concentrations (in tertiles) with hormone outcomes (age- and sex-specific SD-scores) were analysed by linear regression. Primarily, we focused on the EU regulated phthalates; butylbenzyl phthalate (BBzP), di-iso-butyl phthalate (DiBP), di-n-butyl phthalate (DnBP), and di-(2-ethylhexyl) phthalate (DEHP) as well as bisphenol A (BPA). Urinary metabolites of DiBP, DnBP and DEHP were summed and expressed as ∑DiBPm, ∑DnBPm and ∑DEHPm.

RESULTS

Compared to boys in the lowest ∑DnBPm tertile, urinary concentration of ∑DnBPm was associated with concurrent higher luteinizing hormone (LH) and anti-Müllerian hormone (AMH) SD-scores as well as lower testosterone/LH ratio in boys in the middle ∑DnBPm tertile (estimates (CI 95%) 0.79 (0.04; 1.54), 0.91 (0.13; 1.68), and -0.88 (-1.58;-0.19), respectively). Further, higher insulin-like peptide 3 (INSL3) SD-scores and lower DHEAS SD-score in boys in the highest ∑DnBPm tertile (0.91 (0.12; 1.70) and -0.85 (-1.51;-0.18), respectively) were observed. In addition, boys in the middle and highest ∑DEHPm tertile had higher LH (1.07 (0.35; 1.79) and 0.71 (-0.01; 1.43), respectively) and in the highest ∑DEHPm tertile also higher AMH (0.85 (0.10; 1.61)) concentration SD-scores, respectively. Boys in the highest BPA tertile had significantly higher AMH and lower DHEAS concentration compared to boys in the lowest BPA tertile (1.28 (0.54; 2.02) and -0.73 (-1.45; -0.01)), respectively.

DISCUSSION

Our findings indicate that exposure to chemicals with known or suspected endocrine disrupting potential, especially the EU-regulated DnBP, DEHP and BPA, may modify male reproductive hormone concentrations in infant boys suggesting that minipuberty is a critical window sensitive to endocrine disruption.

Review of the Function of the Hypothalamic-Pituitary-Gonadal Axis in Children and Adolescents with Cancer

The most common malignancies in childhood are leukaemias, brain tumours, lymphomas, neuroblastomas, soft tissue sarcomas and kidney tumours. At present, about 80% of childhood cancers can be treated successfully, which has significantly increased long-term survival. Concomitantly, adult gonadal function in childhood cancer survivors has become a concern. However, the immediate effect of cancer and its management on the reproductive axis function has received less attention. We conducted a review of the effects of malignancies and their treatments on the gonadal axis during childhood and adolescence. Some results are controversial, probably because the analyses do not distinguish between the malignancy types, their treatments and/or the age at treatment. However, there is agreement that cancer can partially affect gonadal function before treatment, as revealed by low circulating levels of inhibin B and anti-Müllerian hormone. Subsequently, chemotherapy transiently impairs the somatic component of the gonads (i.e. testicular Sertoli cells and ovarian granulosa cells) with normalization after treatment ends. The impact of chemotherapy may persist through adulthood after more intensive chemotherapy regimens, radiotherapy and conditioning for haematopoietic stem cell transplantation, when there is a severe impairment of the somatic component of the gonads or of the stem germ cells.