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Lifespan Development

13.2 Reproductive and Sexual Changes in Middle Adulthood

Lifespan Development13.2 Reproductive and Sexual Changes in Middle Adulthood

Learning Objectives

By the end of this section, you will be able to:

  • Identify changes in the male and female reproductive systems across middle adulthood
  • Describe physical changes associated with pregnancy and menopause
  • Identify changes in sexual behavior and attitudes across middle adulthood

Fifty-six-year-old Patricia considers herself to be in a happy long-term partnership. Even though sex is less frequent, there is more focus on emotional intimacy, and she is still very satisfied with her sex life. The couple’s physical relationship is nurturing, with lots of affection, and sex is more meaningful, because it is built on shared experiences, respect and acceptance of one another, and knowledge of what each enjoys and dislikes. Overall, Patricia would describe their sexual relationship as loving and complete.

As middle adulthood progresses, people experience changes in their reproductive ability as well as in their sexual behavior and attitudes. The median age of first birth in the United States is now thirty years old, so middle adulthood may include the experience of pregnancy for many. Toward the latter half of middle adulthood, the ability to reproduce declines and then is lost altogether during the life stage known as the climacteric. The associated hormonal transitions can result in a variety of physical changes along with changes to cognition, emotion, and sexual experiences. Most individuals continue to engage in sex throughout middle adulthood, experiencing several physical and cognitive benefits.

Female Reproductive Changes

The female reproductive system undergoes several significant changes over the thirty-year span of middle adulthood. During this stage of life, women typically experience two childbirths (with the associated physical changes), though 15 percent of women forty-five to fifty years old have not had biological children (Korhonen, 2023; Schaeffer & Aragão, 2023). Between the ages of forty and sixty years, the female reproductive system begins to experience changes leading to menopause.

Changes Resulting from Pregnancy

Estrogen and progesterone hormones are produced at their highest rate during pregnancy and are responsible for many changes. For example, females may experience sensation changes to taste (e.g., a greater tolerance for some tastes and a decreased ability to taste), a higher sensitivity to smells, and temporary changes to vision and pressure in the eyes. Body temperature rises slightly during pregnancy, which increases risk of heat stress and dehydration.

Physical changes during pregnancy include growth and tenderness of the breasts as milk production begins. The increase in progesterone also influences a relaxing of ligaments and joints. As a result, many pregnant people will notice they have a flatter arch and longer, wider feet (Segal et al., 2013) and may move to a larger shoe size or more flexibly fitting footwear. Stretch marks may also appear on the skin of the abdomen and breasts as well as the thighs. These skin changes will typically fade over time.

Exercise during pregnancy is recommended for most pregnant persons. According to the Physical Activity Guidelines for Americans, those accustomed to rigorous exercise prior to pregnancy can continue to engage in those activities (U.S. Department of Health and Human Services, 2018). Those who were not exercising prior to pregnancy are generally encouraged to start with moderate activities, such as walking or water aerobics, for thirty minutes a day, five days a week.

Pregnancy-induced changes continue into the postpartum period and beyond. Medical professionals typically recommended that people who have given birth avoid sex for six weeks because the cervix (which has contracted and expanded during birth) needs to heal. During pregnancy and breastfeeding, structures inside the breasts swell to support lactation but shrink when no longer needed. This may result in a smaller breast size (Kahn & Sajjad, 2023). Connective tissue in pregnant people’s bodies becomes more flexible in order to support body shape changes needed for pregnancy and childbirth, and this loosening of connective structures may lead to long-term changes in shape and function of structures throughout the body, including larger feet with lower arches (Alcahuz-Griñan et al., 2021), increased finger joint flexibility (Afshar & Tabrizi, 2021), wider hips (Morino et al., 2019), looser skin, and a drop in the pelvic floor muscles. Changes to the pelvic floor muscles can sometimes cause discomfort during sex as well as incontinence (difficulty controlling urination), especially when jumping or sneezing. Pelvic floor muscles can be gradually strengthened and supported over time by practicing pelvic muscle exercises and learning to conduct everyday physical activities (like lifting children) using proper posture, muscle engagement, and even breathing (Nowogrodzki, 2019).

Menopause

The climacteric results in menopause, the end of the menstrual cycle. Menopause may occur anywhere between forty and sixty years of age and consists of three phases: premenopause, perimenopause, and postmenopause. During the premenopausal phase, females begin to experience irregular menstrual cycles due to fluctuations in estrogen (Figure 13.7). In the perimenopausal phase, even greater variations in menstrual cycles can occur. This phase is often associated with unexpected sensations of feeling hot and increased perspiration (among numerous physical symptoms), commonly referred to as hot flashes. These changes leading up to menopause can occur gradually over eight to ten years. The postmenstrual phase occurs as estrogen and progesterone levels continue to drop and menstruation has ceased for one year.

Illustration showing Female Estrogen Levels Over Adulthood, with levels rising from age 20 to peak levels at 35 years, and then dropping steadily during Menopause (age 40-69) until 80+ years.
Figure 13.7 People assigned female at birth experience fluctuations in estrogen across adulthood, which are associated with changes in fertility. (attribution: Copyright Rice University, OpenStax, under CC BY 4.0 license)

Menopausal changes in hormone levels bring other physical changes beyond the loss of reproductive ability. For example, estrogen helps maintain bone mass, so the drop in estrogen puts women at increased risk of osteoporosis and subsequent skeletal injuries, such as bone fractures (Ji & Yu, 2015) (Figure 13.8). In general, menopause does not cause severe psychological symptoms, though research indicates that Black women in the United States are at greater risk of experiencing menopausal symptoms earlier and to a greater extent than White women because of social disadvantages and disparate treatment (Harlow et al., 2022). Some women report brain fog and issues with memory, and research indicates that estrogen may protect neural health (Goldstein, 2021). Menopause is also associated with a decrease in volume of some areas of the cortex, even when age is controlled for (Schelbaum et al., 2021). However, many reported cognitive concerns can also be attributed to disruption of sleep due to hot flashes and the general stress of middle adulthood. In the postmenopausal phase, cognitive abilities return to a level more consistent with that prior to menopause (Schelbaum et al., 2021).

Graph showing bone mass fluctuations. Bone growth from age 0-30; peak bone mass around 35 years. Decreasing bone mass with age in males after 40; from menopause in females after 50.
Figure 13.8 Declines in estrogen and testosterone during adulthood are associated with bone loss, with persons assigned female at birth experiencing lower peak bone mass and sharper decline in middle adulthood than persons assigned male at birth. (attribution: Copyright Rice University, OpenStax, under CC BY 4.0 license)

The physical and psychological experience of menopause varies individually and cross-culturally. According to research by Hall and colleagues (2007), while most persons AFAB in the United States report experiencing hot flashes during menopause, hot flashes are reported less frequently by females in many Asian countries. Persons AFAB living in modern cultures removed from traditional cultural practices often characterize the transition in terms of discomfort or embarrassment, anxiety, loss of control, and loss of youth, and many see it as a disorder that requires treatment. Persons AFAB in more traditional cultures are more likely traditional cultures are more likely to welcome an increase in wisdom, relief from the responsibility to bear and raise children, and the opportunity to mentor others and start a new chapter of life. Societal influences on perceptions of menopause shape different responses to and management of menopause, including self-care practices such as using cold compresses and controlled breathing, using herbal remedies, seeking out role models and education, acknowledging menopause as a rite of passage and attainment of privilege, and adopting a positive, forward-looking mindset (Hall et al., 2007).

It Depends

Evaluating Hormone Replacement Therapy

In the 1990s, hormone replacement therapy (HRT), consisting of doses of estrogens and progestin, was often prescribed to women to offset symptoms of menopause and reduce the risk of osteoporosis and cardiovascular disease. While observed increases in breast cancer and uterine cancer were associated with long-term high-dosage use, overall mortality was predicted to decrease as a result of the reduced rate of cardiovascular disease (Ross et al., 1989), so it was still recommended that “HRT should be offered to all postmenopausal women” who did not have preexisting risk factors, such as a history of breast cancer (McKeon, 1994).

However, in 2002, longitudinal clinical trials conducted by the Women’s Health Initiative (WHI) on the long-term effects of HRT were stopped prematurely based on results indicating that the risks of breast cancer and CVD were too great for study participants. This drastic action created panic among many patients and doctors, and HRT was no longer considered an advisable treatment (Tormey et al., 2006). However, criticisms of the design of the study, such as that it included women much older than would typically be prescribed HRT, have led some to reconsider the rejection of HRT (Cagnacci & Venier, 2019).

Reanalysis of the original WHI data (Manson et al., 2013) and new clinical trials (Schierbeck et al., 2012) that studied outcomes of HRT by age found that if prescribed within ten years of the onset of menopausal symptoms, the treatment was associated with menopausal symptom relief and a decreased risk of CVD and death. So, what now? The best advice seems to be to talk with your doctor. Dr. Barb DePree, a gynecologist with thirty years of experience, recommends, “Treatment for menopausal symptoms needs to be customized for each woman, given her risk factors, symptoms, and preferences” (DePree, 2019).

Male Reproductive Changes

Like women, men are also more likely to have children after age thirty years. At that same age, however, the fertility of the male reproductive system begins to decline, with a decrease in testicular size and sperm quality beginning in middle adulthood (Vaughan et al., 2020; Well et al., 2007; Zhu et al., 2011). The climacteric is a more gradual process in males than in females. Several changes occur in the male reproductive system that make reproduction less likely but not impossible. Around age forty to forty-five years, sperm cell production decreases, ejaculated semen is lower in overall volume and contains a lower percentage of reproductively viable sperm cells. These changes may occur in large part because around the age of forty years, males experience a 1 percent drop per year in testosterone production (Figure 13.9). This hormonal decrease is also associated with loss of muscle mass and strength, increased fatigue, and increased risk of osteoporosis (Rajfer, 2003; Singh, 2013).

Illustration showing Male Testosterone Levels Over Adulthood, with peak levels in 20s and 30s, then medium levels in 40s to 60s, and low levels in 70s and 80s.
Figure 13.9 Testosterone levels in individuals assigned male at birth decrease gradually throughout adulthood. (attribution: Copyright Rice University, OpenStax, under CC BY 4.0 license)

There has been a rise in the use of testosterone replacement therapy to treat reduced testosterone production in adult males, though its use is not without controversy. Some studies show health benefits such as improved mood and bone density (Snyder et al., 2018), while others suggest health concerns such as increased risk of stroke (Loo et al., 2017).

One of the most common afflictions in middle adulthood is erectile dysfunction (ED), the inability to achieve or maintain an erection. Roughly 31 percent of men between ages fifty-seven and sixty-four years have ED (Castleman, 2017). Predictors include physical factors like low testosterone and obesity, as well as a host of health-related factors like diabetes and hypertension and psychological aspects such as depression. Erectile dysfunction is associated with increased risk of cardiovascular disease and dementia (Kessler et al., 2019). The most common treatment is the use of vasodilator medications (such as Viagra and Cialis). Originally designed to control hypertension, these drugs increase blood flow to the penis. Pelvic floor exercises have also been demonstrated to be an effective therapy for ED (Dorey et al., 2004; Yaacov et al., 2022).

Changes in Sexual Activity

In middle adulthood, individuals generally remain sexually active, despite declines in frequency of sexual activity. Changes in marital status due to divorce or widowhood, as well as time demands from children and jobs, may reduce opportunities for sexual activity. Poorer physical health (rather than reproductive changes) also predicts a reduction in sexual activity (Karraker et al., 2011).

AARP surveys how middle-aged (aged forty-five to fifty-nine years) and older (aged sixty-plus years) adults value and engage in sex (Fisher et al., 2010). Midlife adults place more value on sex than older adults, though many see it as less important as they age. Through midlife, men tend to think about and be more interested in sex than women. Thirty-three percent of men and 23 percent of women surveyed reported having sex at least once a week. Another important finding in AARP’s research is that, for middle-aged women, the quality of the relationship with their sexual partner influences the regularity of sexual activity and the positivity of life satisfaction. When asked what they enjoy most about sex in middle adulthood, adults (and especially women) cited their psychological and romantic connection to their sexual partners, including emotional intimacy, comfort, communication, quality time, and affection (Flanigan, 2023; Koch & Mansfield, 2007; Lodge & Umberson, 2012) (Figure 13.10).

A couple hold hands and kiss.
Figure 13.10 In middle adulthood, women seek intimacy, love, companionship, and affection from their sexual partners. (credit: modification of work “Sa Pa kiss” by “Newone”/Wikimedia Commons, CC BY 3.0)

Continued sexual activity is associated with increased psychological and cognitive health, including reduced risk of depression, and those who are healthy and active report enjoying their sex life more (Fisher, et al., 2010; Jackson et al., 2019). The association between sexual activity and well-being is likely a bidirectional influence. Depression or poor health may cause a person to withdraw from social connections and avoid physical activity, including sexual intimacy. On the other hand, experiencing sexual intimacy may increase an adult’s feelings of belongingness and relational intimacy, which may boost mood and protect against depression. Research also finds positive correlations between sexual activity and cognitive functions and memory (Wright et al., 2019), even when controlling for other variables such as age, education, loneliness, and physical health. Researchers have speculated that the release of neurotransmitters such as dopamine and oxytocin in response to sexual activity may enhance cognitive activity (Wright & Jenks, 2016).

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