摘要：Objectives. We examined the association between childhood abuse and early menarche in a sample of US Black women. Methods. We conducted multivariable log-binomial regression on data from 35 330 participants in the Black Women's Health Study to estimate risk ratios and 95% confidence intervals for the relation of childhood physical and sexual abuse with early age at menarche (i.e., < 12 years). Results. In adjusted analyses, sexual abuse was positively associated with early menarche, and the risk of early menarche increased with increasing frequency of sexual abuse incidents. We observed a weak but statistically significant association between physical abuse and early menarche. Associations between sexual abuse and early menarche were stronger when we used a more stringent cutpoint for early menarche (i.e., < 11 years). Conclusions . Our data suggest an increased risk of early menarche among Black women who experienced childhood sexual abuse. Evidence for an association between childhood physical abuse and early menarche was equivocal. Age at menarche is an important predictor of women's health across the lifespan. Early age at menarche is associated with earlier age at initiation of sexual activity 1 and first pregnancy 1 , 2 and is a risk factor for several adult conditions, including gynecologic disorders, 3 obesity, 4 cardiovascular disease, 5 autoimmune diseases, 6 – 8 and cancer. 9 , 10 Established risk factors for early menarche include increased growth velocity, 11 overweight or obesity, 11 physical inactivity, 11 , 12 high fat intake, 13 and genetics. 11 , 12 Several psychosocial risk factors for early menarche have also been identified, including absence of the father, 14 – 16 parental conflict, 16 , 17 and family tension. 15 , 18 – 20 US studies indicate a decrease in pubertal age over the past several decades of 6 months to 1 year in all ethnic groups. 21 – 23 In addition, national data show that non-Hispanic Black girls experience menarche at a significantly earlier age than do non-Hispanic White and Mexican American girls. 23 The reasons for the racial discrepancy in menarcheal age are largely unknown, but differences in early life nutritional factors or adiposity may play a role. 23 Some studies suggest that childhood abuse can influence reproductive end points, including ovarian hormone metabolism, 24 preterm birth, 25 and timing of the menopausal transition. 26 To our knowledge, 4 studies have evaluated the association of childhood abuse with age at menarche. 27 – 30 All 4 found a positive association between childhood sexual abuse and early menarche. 27 – 30 Of the 2 studies that examined the role of childhood physical abuse, 28 , 29 1 found a weak positive association for physical abuse after control for sexual abuse, 29 and the other found a strong positive association for physical abuse but did not adjust for sexual abuse. 28 An association between childhood abuse and early onset of menarche is biologically plausible. Childhood sexual trauma can affect the hypothalamic–pituitary–adrenal axis, the limbic system, and possibly gene expression of hormone receptors in the brain, with abuse being associated with chronic activation of the hypothalamic–pituitary–adrenal axis. 31 – 34 Chronic activation of this axis, in turn, may influence gonadotropin levels and ovarian function via alterations in the hypothalamic–pituitary–ovarian axis. 35 – 37 Less is known about how physical abuse may influence ovarian function, but results of 1 earlier study suggest that its effects, assuming the same mechanism, may be smaller than that of sexual abuse. 29 Retrospective surveys indicate that 5% to 25% of North American women have experienced some form of childhood sexual abuse, 38 – 43 and the prevalence of childhood physical abuse is estimated to be 13% to 28%. 39 – 44 Although the prevalence of childhood sexual abuse is estimated to be greater for Blacks (8%–19%) than for Whites (6%–9%) or Hispanics (5%–8%), these differences attenuate after adjustment for sociodemographic and family background characteristics. 38 , 44 Studies conducted to date on childhood abuse and age at menarche were limited in sample size (ranging from 323 27 to 816 29 participants) and included few Black women. All but 1 study 29 either focused exclusively on sexual abuse 27 , 30 or failed to control for sexual abuse in the assessment of physical abuse. 28 A larger study was needed to assess the independent associations of childhood sexual and physical abuse with early menarche, particularly among Black women, who experience menarche earlier on average than do other ethnic groups and, possibly, more childhood abuse. To investigate these associations, we analyzed data collected from more than 35 000 Black women participating in a national cohort study.
