Timing of menopause and patterns of menstrual bleeding.

Age at menopause is associated with a variety of health outcomes. Menstrual histories, both as markers of physiologic function and through their potential association with age at menopause, have also been investigated for their links to health outcomes. This study used data from a cohort of women from the United States who provided prospectively recorded data on their menstrual cycles for many years. Dr. Alan Treloar (University of Minnesota) originally recruited the women in the 1930s; the authors used data reported by these women from 1930 through 1977. They identified nuanced characteristics of menstrual histories that were strongly predictive of the onset of menopause, focusing on measures of central tendency (the mean), variability (standard deviation), and serial irregularity (approximate entropy), the last of which quantifies a continuum that ranges from totally ordered to completely random. They controlled for other characteristics known to affect age at menopause, including use of exogenous hormones, number of births, and extent of breastfeeding. Although cycle length and variability increased with the approach of menopause, the authors found that serial irregularity decreased and was a strong predictor of its onset. This finding constitutes an important piece of information not attainable with conventional statistical summaries of menstrual histories.

Menarcheal age and subsequent patterns of family formation.

We examine whether age at menarche affects age at first marriage or first birth using two samples of U.S. women. Data are drawn from the Tremin Trust, a longitudinal study of menstrual cycles that recruited white women who were students at the University of Minnesota and from a survey of a nationally representative sample of white women born between 1900 and 1910. Regression models with cubic splines were used to analyze the relationship between age at menarche and age at first marriage. Cox proportional hazard models were used to examine the effect of age at menarche on the interval between marriage and first birth. Unlike earlier work, we found that once secular trends in both age at marriage and age at menarche were taken into account, there was no evidence that age at menarche affects either age at marriage or the timing of first births in these U.S. women.

Ependymomas of the third ventricle.

Third ventricular ependymomas are rare tumors that have not been specifically examined. Four cases of these tumors are reported. The presenting symptoms included headache, ataxia, vertigo, and Parinaud's syndrome. All the patients underwent computed tomographic scanning and cerebral angiography, followed by craniotomy and microsurgical resection of the tumor. In addition, all patients had or developed symptomatic obstructive hydrocephalus requiring shunting procedures. Three of the patients are alive with a follow-up of 4 to 12 years. It is remarkable that these tumors are so rare, given that the ependymal surface area of the third ventricle is greater than that of the fourth. The management of these tumors should include aggressive surgical resection, radiation therapy, and cerebrospinal fluid diversion.

Subacute cervical spine instability.

A case of delayed onset of C5-6 subluxation after a motor vehicle accident, with normal initial cervical spine roentgenograms and neurological findings consistent with concomitant cerebral trauma, is presented. Damage to the cervical spine was due to fractures of the C-6 body and superior articular facet undetected by routine radiologic studies.