The evolution of menopause and human life span.

Noteworthy data is emerging to support the existence of longevity-enabling genes. Our observations of the relationship between reproductive fitness and longevity among centenarians support theories that posit strong selective forces in the determination of how fast humans age and their susceptibility to diseases associated with ageing. Current data support the idea that there is no selective advantage for humans to have a lifespan of approximately 100 years. Rather, getting to such a very old age may be a by-product of longevity-enabling genes that maximize the length of time during which women can bear children, and during which they can increase the survival probabilities of their children and grandchildren. We thus review the literature pertaining to the relationship between reproductive fitness and longevity.

Preventive health services received by minority women aged 45-64 and the goals of healthy people 2000.

We attempted to evaluate the preventive health services received by minority women aged 45-64 in an underserved region of Boston. We compared two surveys of disease burden and preventive health services to national data sets and the goals of Healthy People 2000. We found that minority women seen both in community health centers and within the community had many cardiovascular risk factors (41-45% had hypertension, 24-29% had cholesterol > 200 mg/dL, and 49-56% had a body mass index of >27.3 kg/m(2)). Women reported that they received low rates of counseling on healthy behaviors but generally received breast and cervical cancer screening. Forty-three percent of women who were interviewed in the community had no health insurance and these women were less likely to have received a Papanicolaou test or mammogram than insured women. Lack of insurance did not predict cancer screening for women already being seen in the community health clinic.

Determinants of unexplained antepartum fetal deaths.

OBJECTIVE: To assess fetal, maternal, and pregnancy-related determinants of unexplained antepartum fetal death. METHODS: We conducted a hospital-based cohort study of 84,294 births weighing 500 g or more from 1961-1974 and 1978-1996. Unexplained fetal deaths were defined as fetal deaths occurring before labor without evidence of significant fetal, maternal, or placental pathology. RESULTS: One hundred ninety-six unexplained antepartum fetal deaths accounted for 27.2% of 721 total fetal deaths. Two thirds of the unexplained fetal deaths occurred after 35 weeks' gestation. The following factors were independently associated with unexplained fetal death: maternal prepregnancy weight greater than 68 kg (adjusted odds ratio [OR] 2.9; 95% confidence interval [CI] 1.85, 4.68), birth weight ratio (defined as ratio of birth weight to mean weight for gestational age) between 0.75 and 0.85 (OR 2.77; 95% CI 1.48, 5.18) or over 1.15 (OR 2.36; 95% CI 1.26, 4.44), fewer than four antenatal visits in women whose fetuses died at 37 weeks or later (OR 2.21; 95% CI 1.08, 4.52), primiparity (OR 1.74; 95% CI 1.26, 2.40), parity of three or more (OR 2.01; 95% CI 1.26, 3.20), low socioeconomic status (OR 1.59; 95% CI 1.14, 2.22), cord loops (OR 1.75; 95% CI 1.04, 2.97) and, for the 1978-1996 period only, maternal age 40 years or more (OR 3.69; 95% CI 1.28, 10.58). Trimester of first antenatal visit, low maternal weight, postdate pregnancy, fetal-to-placental weight ratio, fetal sex, previous fetal death, previous abortion, cigarette smoking, and alcohol use were not significantly associated with unexplained fetal death. CONCLUSION: In this study, we identified several factors associated with an increased risk of unexplained fetal death.

Causes of fetal death in women of advanced maternal age.

OBJECTIVE: To examine which causes of fetal death occur more often in older women and to determine whether these causes have changed significantly since the 1960 s and early 1970 s. METHODS: Data from the McGill Obstetrical Neonatal Database were used to calculate rates of specific causes of fetal death in women younger than 35 and in women 35 years or older. Among the 101,640 births between 1961 and 1995, there were 715 stillbirths and 822 neonatal deaths. The autopsy rate was 97% and categorization of the causes of fetal death remained consistent over this 34-year period. The rates of specific causes of fetal death per 10,000 total births were determined for an earlier period (1961-1974) and a later period (1978-1995). RESULTS: Compared with the 1961-1974 period, there was a 60% reduction in the rates of both fetal and neonatal deaths during 1978-1995 (P < .001). During 1961-1974, women 35 years or older were more likely than their younger counter-parts to have fetal death due to lethal congenital anomalies (odds ratio [OR] 3.2; 95% confidence interval [CI] 1.5, 6.5); this was no longer true in the 1978-1995 period. From 1978 to 1995, older women were at a statistically significant increased risk for "unexplained" fetal death (OR 2.2; 95% CI 1.3, 3.8); women 35 years of age or older had approximately one in 440 births end in unexplained fetal death, compared to one in 1000 births for women younger than 35. CONCLUSIONS: Advanced maternal age is no longer associated with an increased risk for fetal death due to congenital anomalies. However, older women have a significantly higher risk for unexplained fetal death. The identification of those maternal and fetal characteristics that contribute to unexplained fetal death and its prevention remain important challenges for contemporary obstetric practice.

Increased maternal age and the risk of fetal death.

BACKGROUND: Although the fetal death rate has declined over the past 30 years among women of all ages, it is unknown whether particular characteristics of the mother, such as age, still affect the risk of fetal death. We undertook a study to determine whether older age, having a first child (nulliparity), or other characteristics of the mother are risk factors for fetal death. METHODS: We used data from the McGill Obstetrical Neonatal Database to evaluate risk factors for fetal death among all deliveries at the Royal Victoria Hospital in Montreal (n = 94,346) from 1961 through 1993. Data were available for two time periods (1961 through 1974 and 1978 through 1993); data for 1975 through 1977 have not been entered into the data base and were therefore not included. Using logistic regression, we estimated the effect of specific maternal characteristics and complications of pregnancy on the risk of fetal death. RESULTS: The fetal death rate decreased significantly from 11.5 per 1000 total births (including live births and stillbirths) in the 1960s to 3.2 per 1000 in 1990 through 1993 (P < 0.001). Between these periods, the average maternal age at delivery increased from 27 to 30 years (P < 0.001), and the frequency of the diagnosis of diabetes and hypertension during pregnancy increased fivefold (P < 0.001). Nevertheless, after we controlled for these and other maternal characteristics, women 35 years of age or older continued to have a significantly higher rate of fetal death than their younger counterparts (odds ratio for women 35 to 39 years of age as compared with women < 30 years of age, 1.9; 95 percent confidence interval, 1.3 to 2.7; for those 40 or older, 2.4; 95 percent confidence interval, 1.3 to 4.5). CONCLUSIONS: Changes in maternal health and obstetrical practice have resulted in a 70 percent decline in the rate of fetal death among pregnant women of all ages since the 1960s. Advancing maternal age, however, continues to be a risk factor for fetal death.

The impact of extreme prematurity and congenital anomalies on the interpretation of international comparisons of infant mortality.

OBJECTIVE: To identify the potential impact that different definitions of live births and practice patterns have on infant mortality rates in England and Wales, France, Japan, and the United States. METHODS: United States data were obtained from the 1986 linked national birth-infant death cohort, and those for the other countries came from either published sources or directly from the Ministries of Health. RESULTS: In 1986 in the United States, infants weighing less than 1 kg accounted for 36% of deaths (32% white and 46% black); 32% resulted from fatal congenital anomalies. These rates were much higher in both categories than in England and Wales in 1990 (24 and 22%, respectively), France in 1990 (15 and 25%, respectively), and Japan in 1991 (9% for infants weighing less than 1 kg, percentage of fatal congenital anomalies unknown). These cases are more likely to be excluded from infant mortality statistics in their countries than in the United States. CONCLUSIONS: In 1990, the United States infant mortality rate was 9.2 per 1000 live births, ranking the United States 19th internationally. However, infant mortality provides a poor comparative measure of reproductive outcome because there are enormous regional and international differences in clinical practices and in the way live births are classified. Future international and state comparisons of reproductive health should standardize the definition of a live birth and fatal congenital anomaly, and use weight-specific fetal-infant mortality ratios and perinatal statistics.

The changing pattern of fetal death, 1961-1988.

The aim of this study was to assess any changes in cause-specific fetal death rates in the nonreferred population of a tertiary care unit. The fetal death rate (per 1000 births) among 88,651 births diminished from 11.5 in the 1960s to 5.1 in the 1980s. Fetal death due to intrapartum asphyxia and Rh isoimmunization has almost disappeared. Toxemia and diabetes continue to make similar and small contributions to fetal death rates. There has been a significant decline in unexplained antepartum fetal deaths and in those caused by fetal growth retardation, but no significant change in the death rate due to intrauterine infection or abruptio placentae. During the 1960s, the risk of fetal death was increased in women with hypertension, diabetes, or a history of stillbirth; during the 1980s, only women with a history of insulin-dependent diabetes were at risk. Improved application of current knowledge may help decrease the fetal death rate caused by fetal growth retardation. Reduction in deaths due to abruptio placentae, intrauterine infections, or lethal malformations, as well as unexplained antepartum deaths, appears to depend on better understanding of the etiology of these disorders.