Discussion of effects sex can have on different aspects of health including cardiovascular, pain perception, and brain health. Special issues between sex and situations such as pregnancy, diabetes, and heart disease. Tips for addressing worries about physical health and sex, including supporting one’s partner.

Spontaneous preterm birth (PTB) refers to a delivery that occurs between weeks 20 and 37 of pregnancy, due to preterm labor, preterm prelabor rupture of membranes. and short cervical length at mid-trimester. The three most common risk factors for PTB are (1) prior history of preterm delivery, (2) twin pregnancy, and (3) short cervix at mid-trimester ultrasound. Several studies have demonstrated that short cervical length is the most powerful predictor for PTB in the index pregnancy for both singleton and twin pregnancies. A short cervical length means the measured length of the cervix is shorter than expected for the current gestational age, with a cutoff value between 20 and 25 mm. Sexual intercourse by itself has not been demonstrated to be a clear risk factor for PTB. Thus, abstinence after pregnancy has been achieved has no role in strategies for prevention of PTB. Also, most sexual positions and noncoital activities (e.g. oral sex, masturbation) during late pregnancy are not clearly associated with adverse pregnancy outcomes. There is no strong evidence that sexual activity affects the risk of PTB or onset of labor in healthy individuals. Pelvic rest may be recommended in selected cases, such as patients with a very short cervix or bulging membranes.

Twin and triplet pregnancies have been associated with an increased risk for adverse maternal and neonatal outcomes. This chapter discusses select issues about sexual activity and twin pregnancy, especially with relation to preterm birth (PTB) and shortened cervix, two major concerns in this population. Two studies addressed the association of sexual activity with PTB in twin pregnancies. Overall, these studies do not support a relationship between sexual behavior and PTB in uncomplicated twin pregnancies. Unanswered questions still abound regarding twin gestations at higher risk of PTB, the effects of prostaglandins in semen on cervical length, the intensity of uterine contractions with orgasm on a compromised cervix, and sexual activity in the case of cervical cerclage. We suggest that sexual activity of any type should not be discouraged in twin gestations without other obstetric risk factors such as short cervix. Recommendations should be individualized bearing in mind patient history, comorbidities, and emotional needs.

The physical and psychological changes a woman undergoes during pregnancy impact various areas of her life, including her sexual life. Sexuality during pregnancy is important, as there is a strong link between sexual satisfaction and overall life satisfaction. Women’s sexual response, classically divided into four stages (excitement/arousal, plateau, orgasm, and resolution), is more complex. Several hormones are involved in sexual arousal, such as oxytocin, β-endorphin, and prolactin. The effect of orgasm during pregnancy has not been well studied and available evidence is lacking. In the absence of evidence of harm, it seems reasonable to conclude that orgasm is safe in pregnancy, at least in low-risk ones.

Medical guidelines addressing sexual intercourse during pregnancy are lacking. However, patients can find an abundance of information on the web. In short, sex during normal pregnancy is permitted. The most common reasons for abstaining from sex in pregnancy are placental problems, ruptured membranes, and pregnancies in which there is a high likelihood of premature labor. Orgasms are safe, as are oral and anal sex, as long as intercourse is not forbidden and different sexual positions are acceptable but it is preferable not to lie on the back.

The chapter considers the range of features that enable investigators to describe a killing as ‘sexual’, such as clothes removed, objects inserted into the body and presence of seminal fluids on the body. Some killing done in association with sexual behaviour is not motivated by lust. For example, it might represent an attempt to avoid capture following a sexual assault or the accidental result of choking. Some killers reach orgasm from simply cutting a victim, while others (e.g. David Berkowitz) are sexually aroused by shooting a courting couple. The chapter describes a number of common features of a ‘composite killer’, such as cruelty to animals and voyeurism. Various ruses might be used in order to get a victim in the situation where he or she can be killed, such as offering a lift or seeking help. However, the most common method appears to be to engage the services of a sex worker.

This chapter examines and defines a number of terms fundamental to understanding women including sex, gender, gender identity, gender roles, sexual orientation, sexual identity, sexual and gender fluidity, and gender/sex. Although these aspects of being a woman are connected, they are nonetheless distinct. To understand what it means to be a woman, it is important to understand the complexities of each of these concepts both within and across cultures as well as to take an intersectional approach that considers all of a woman’s identities. We propose that the answer to the question of who is a woman is that women are those individuals who identify as being a woman, regardless of their sex assigned at birth, gender roles, sexual orientation, or sexual identity. We also concluded that although there are certainly some biological differences between men and women, women’s sexuality and sexual well-being can be best understood from a social constructionist perspective that takes sociocultural influences into account.