Diurnal variation of gonadotropin levels in girls with early stages of puberty

Abstract

Purpose Pubertal gonadotropin secretion shows circadian pattern and the luteinizing hormone (LH) levels tend to rise in later stages of puberty in girls. We studied the usefulness of basal LH in the evaluation of central precocious puberty with emphasis on the influence of sampling time.Methods Medical records of 334 girls that underwent gonadotropin-releasing hormone stimulation test (GnRHST) were reviewed. Auxological and laboratory data were compared between those with early morning (EM, before 10 AM) and late morning/afternoon (LM/A, after 10 AM) basal samples.Results Among those in sexual maturity rating (SMR) 2, EM samples showed higher basal LH (P=0.004) compare to LM/A samples, whereas those in SMR 3 showed no difference in LH levels between EM and LM/A samples. Among girls with pubertal response, EM group showed higher basal LH (P=0.031) and follicular stimulating hormone (P=0.008) than LM/A group. The EM basal LH was more closely related with the peak stimulated LH than the LM/A basal LH did (rs=0.871 vs. rs=0.524). The optimal basal LH cutoffs to predict a pubertal response to GnRHST were 0.11 IU/L with a sensitivity of 66.7% and a specificity of 78.7% in EM group, and 0.07 IU/L with a sensitivity of 60.0% and a specificity of 78.9% in LM/A group, respectively.Conclusions In girls with early stages of puberty, EM basal LH is a more sensitive screening tool than the LM/A basal LH. Diurnal variation should be considered in evaluating children with precocious puberty.

Morning basal luteinizing hormone, a good screening tool for diagnosing central precocious puberty

“…LH secretion during early puberty shows a circadian pattern due to nocturnal gonadotropin secretion [37], which results in decreased pulsatile LH secretion after waking. The mLH is also more sensitive than late morning/afternoon LH for screening girls in the early stages of puberty [22]. Because the circulating half-life of LH is 80–130 minutes [20], random daytime measurements of gonadotropins are likely to be incorrect.…”

“…As puberty progresses, this sleepwake difference decreases, and increased amplitude of LH pulse secretion is detected during the daytime [3,19-21]. Furthermore, early morning basal LH is more sensitive than late morning/afternoon LH for CPP screening of girls in early stages of puberty [22]. Because the circulating half-life of LH is 80–130 minutes [20], LH sampling should be performed within 2 hours after waking for accurate results.…”

Slower progression of central puberty in overweight girls presenting with precocious breast development

“…Analytical sensitivity was 0.07 U/L for LH, 0.3 U/L for A c c e p t e d A r t i c l e there was strong suspicion of rapid pubertal progression, associated with psychosocial stress from anxiety on the probability of early menarche. For LHRH test, LH and FSH levels were measured at baseline and at 30, 45, 60, and 90 min after IV administration of GnRH 0.1 mg (10). In the remaining 18 children, pubertal progression was confirmed by basal LH levels.…”

Gonadotropin-releasing hormone stimulation test and diagnostic cutoff in precocious puberty: a mini review

“…4,13) Meanwhile, to minimize variation due to diurnal LH preferences in early phases of puberty, early-morning samples (before 10 AM) are desirable. 15) In addition, caution is needed in obese children as the peak response tends to be lower due to excess androgen and estrogen that suppress LH in obesity. 16,17) At Tanner stage 2, LH peaks have been shown to be significantly lower in obese and in overweight girls in comparison to normalweight girls (9.1±6.1, 10.4±6.4, and 11.9±7.5 IU/L, respectively).…”

“…Repeated GnRH tests can be performed in conjunction with other modalities, such as pelvic and abdominal ultrasound (to assess fundal/cervical ratio, uterus length, and ovarian volume), bone age assessment, and genetic studies [ 4 , 13 ]. Meanwhile, to minimize variation due to diurnal LH preferences in early phases of puberty, early-morning samples (before 10 AM) are desirable [ 15 ]. In addition, caution is needed in obese children as the peak response tends to be lower due to excess androgen and estrogen that suppress LH in obesity [ 16 , 17 ].…”