Mortality rates improved for both women and men in the second half of the 20th century. But these rates improved more rapidly for women than for men, so that until recently, the gender gap in life expectancy increased. In 1920, life expectancy at birth for females was two years greater than for males. By the 1970s, the female advantage was over seven years, but has declined since then, to six years in 1998 (when life expectancy was 74 for males, 80 for females).
Historically in the United States, young women ran a high risk of dying during or after childbirth. Thanks to improved prenatal and obstetric care, death rates from pregnancy-related causes have fallen to very low levels.
Today, women have lower mortality rates at every age. Men are three times as likely as women to die from injuries (unintentional injuries, suicide, or homicide), and progress against those causes of death has been much slower than against other causes in the last 50 years. There is also evidence that men at all ages are less likely to seek medical care and less likely to comply with medical instructions than are women.
The widening of the gap during most of the 20th century can be attributed primarily to the fact that men smoked more than women. But in recent decades, the prevalence of smoking among women has increased while the prevalence among men has declined.
The leading cause of death among men is heart disease, but among women, deaths from heart disease recently have fallen below the number of cancer deaths. Women's higher levels of estrogen seem to provide protection against the incidence and severity of heart disease. In recent decades, the growth of estrogen replacement therapy for older women has also helped reduce deaths from heart disease.
