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Pubertal Development and Menarche
Published in Jane M. Ussher, Joan C. Chrisler, Janette Perz, Routledge International Handbook of Women’s Sexual and Reproductive Health, 2019
This physiology is multifaceted and not completely understood. One pubertal process is clinically known as gonadarche, involving the reactivation of the hypothalamus-pituitary-gonadal (HPG) axis. This axis is active in fetal development but becomes inactive until puberty when the hypothalamus secretes gonadotropin-releasing hormone (GnRH), which stimulates the anterior pituitary to release luteinizing hormone (LH) and follicle stimulating hormone (FSH) to the gonads, in girls, the ovaries. In turn, LH and FSH stimulate the ovaries to produce estradiol. The increase in estradiol is first externally noticeable with breast bud development, known as thelarche (Dorn & Rotenstein, 2004). Along with an increase in other hormones throughout early puberty, menarche eventually occurs in mid to late puberty; menstruation becomes cyclical and ovulatory later, about one year after menarche, for most girls (Hillard, 2014).
Problems with puberty and its onset
Published in David J Cahill, Practical Patient Management in Reproductive Medicine, 2019
In boys, the first physical evidence of puberty is the growth in testicular volume and penis size (gonadarche). The growth spurt in boys starts after genital and gonadal growth begins. This is followed by the appearance of pubic and axillary hair (called pubarche in boys) (10). The growth spurt generally is completed by the age of 16, long after all the other signs of puberty are complete.
Changes in the vulva and vagina throughout life*
Published in Miranda A. Farage, Howard I. Maibach, The Vulva, 2017
Miranda A. Farage, Howard I. Maibach, Aikaterini Deliveliotou, George Creatsas
Maturation of the adrenal glands and androgen secretion (adrenarche) begins at about 6 years of age, approximately 2 years before pituitary–gonadal maturation and the production of ovarian steroid hormones (gonadarche). Because adrenarche and gonadarche proceed independently, the appearance of pubic hair does not provide information about pituitary–ovarian maturation. Pubic hair development elicited by androgens proceeds in five stages, as described by Tanner (Figure 3.3) (19): No pubic hair.Sparse hair appears on the labia majora and the mons pubis along the midline.Thickness and coarseness of the hair increase, with coverage of the lobes of the labia majora and increased lateral growth from the midline of the mons pubis.Hair growth increases such that only the upper lateral corners of the mature triangular configuration are deficient.Adult pattern, attained between the ages of 12 and 17 years, with a characteristic horizontal upper margin on the mons pubis just above the limit of the genitofemoral folds.
The First Ejaculation: A Male Pubertal Milestone Comparable to Menarche?
Published in The Journal of Sex Research, 2020
Physiological events that occur at puberty are typically triggered by hormonal patterns. For instance, the events of adrenarche are triggered by androgens released from the adrenal cortex (Parker, 1991), gonadarche is triggered by pituitary gonadotropins (Abreu & Kaiser, 2016), and menarche is triggered by a series of hormonal processes ultimately leading to the shedding of the uterine lining (Karapanou & Papadimitriou, 2010). Does thorarche also have an explicit biological trigger? Hormones do affect the onset of ejaculation, and treating adolescent boys with testosterone has been found to increase the occurrence of nocturnal emissions (Finkelstein et al., 1998). However, hormones are not a direct trigger of thorarche, as boys can voluntarily choose to induce a first ejaculation themselves, pursuant to Tanner’s notion that culture can influence its timing. Nonetheless, thorarche does still occur in the absence of voluntary ejaculation, typically through a nocturnal emission, and some boys have reportedly been surprised to accidentally experience a first ejaculation while awake without the intention of masturbation (Kinsey, 1948). Thus, there is evidently some sort of innate biological mechanism to ensure ejaculation occurs in adolescence even in the absence of cultural influences.
Determination of estrone sulfate, testosterone, androstenedione, DHEAS, cortisol, cortisone, and 17α-hydroxyprogesterone by LC-MS/MS in children and adolescents
Published in Scandinavian Journal of Clinical and Laboratory Investigation, 2020
Carina Ankarberg-Lindgren, Mats X. Andersson, Jovanna Dahlgren
The average T concentrations in prepubertal girls were higher than expected [9,34,37,38], which probably reflects the selection of samples. The group with Tanner breast stage 1 may include true prepubertal girls as well as girls in early puberty (gonadarche) yet without signs of breast development. Previous studies have shown that girls in early puberty have significantly higher T concentrations compared to prepubertal girls [34,37,38]. Hence, a mixture of prepubertal and early pubertal girls with Tanner breast stage 1 is likely the cause for the finding that girls have higher T concentrations compared to boys before start of puberty.