The Sex Side of Life (1919) by Mary Ware Dennett

By: Malladi Lakshmeeramya

The Sex Side of Life (1919) by Mary Ware Dennett

Mary Ware Dennett, an activist in the US for birth control and sex education in the early twentieth century, wrote an educational pamphlet in 1915 called The Sex Side of Life, and it was published in 1919. The pamphlet defined the functions of the sex organs, emphasized the role of love and pleasure in sex, and described other sexual processes of the body not usually discussed openly. In the early twentieth century in the US, individuals did not have wide access to sex education due to the limitations enforced by the Comstock Act, which prohibited the distribution and discussion of topics that were considered obscene. In 1929 the US tried Dennett for mailing her pamphlet as a violation of the Comstock Act, sending obscene material through the United States Postal Service. Dennett’s pamphlet The Sex Side of Life, and her subsequent trial, United States v. Dennett, contributed to a national discussion about sex education and human reproduction and led to the revision of reproduction-related obscenity laws.

During the early 1900s, in Boston, Massachusetts, Dennett participated in numerous social reform groups that challenged the Comstock Act including groups focused on women’s rights to obtain birth control and disseminate sex education. In 1913 Dennett and her husband divorced and she became solely responsible for raising their two sons, Carlton and Devon. When Dennett’s eldest son, who was 14, started asking her about sex, she recalled looking to other literature and finding it inadequate. In response, Dennett wrote her own sex education pamphlet, The Sex Side of Life.

According to historian Constance Chen, Dennett’s essay, which later became a pamphlet, received good feedback from her eldest son, prompting Dennett to start sending it to her friends with young children. By word of mouth, knowledge about the success of Dennett’s essay spread among parents. In 1918 The Medical Review of Reviews aimed to publish an article about sex education. The magazine approved of Dennett’s essay and published the essay as an article in the 1918 February edition of the magazine. In the years following that, Dennett authored seven editions of the pamphlet and sold 35,000 copies to teachers, parents, doctors, and individuals in other fields.

Dennett divides her 16-page pamphle The Sex Side of Life into two sections:  "Introduction for Elders" and "An Explanation for Young People." In the section, "Introduction for Elders," Dennett explains that she found most sex education materials of the time to be dishonest and unsafe to give to her children. In the pamphlet, she argues that parents tell their children incorrect information about sex either due to embarrassment or due to a lack of knowledge. Dennett makes four claims about why the books she looked at were inadequate to give to her own children and why they are inadequate to teach any child about sex education. Her first claim is that instead of using real names for the sex organs, educators use poetic or colloquial references that confuse children. Second, sex is described to children by teaching them about the reproduction of plants and animals instead of directly discussing the reproduction of humans. Dennett argues that that leaves children without knowledge to understand and solve problems associated with maturing sexually. Third, Dennett contends that, children are taught to fear sex outside of marriage, causing them to fear both the sex act itself and their natural sexual instincts. Dennett’s final claim is that sex is never taught from an emotional perspective, denying children a true understanding of sex. According to Dennett, she sought to rectify all of those shortcomings in her pamphlet The Sex Side of Life.

Dennett continues “Introduction for Elders” by describing how her pamphlet is different from those others she had read. She states that she provides real names for the sex organs and does not employ metaphors describing how human reproduction is like that of plants and animals. Dennett emphasizes that she tried to eliminate fear of sex by discussing sexually transmitted diseases and explaining that sex is a beautiful occurrence. Dennett ends her introduction by justifying her pamphlet with the statement that with knowledge, children will have more self-control, avoid meaningless sex, and have a successful sex life after growing older.

In the second section of her pamphlet, titled “An Explanation for Young People,” Dennett addresses her audience, teenage children asking questions about sex. Dennett urges her readers to stop feeling ashamed of their curiosity about sex and to understand that while adults know more about the topic, they might not know everything. She states that the children’s sex sides, a combination of their mind, body, and emotions, have been developing since birth and are important and beautiful aspects of maturing. She then describes that humans are not like plants and animals because a person’s desire for sex comes from their love for another individual, an emotion plants and animals cannot express. In addition, Dennett argues that only humans can fall in love and that their attractions to another humans are influenced by their minds and souls.

Dennett then transitions to describing the sex organs, conception, and labor. She includes two diagrams, one of a male’s reproductive anatomy and one of a female’s. Each diagram is labeled with numbers that correspond to brief descriptions of the function of each organ within the reproductive system. For example, Dennett describes the vagina as the location where the penis inserts. She explains that conception occurs after the sex act, when the male and female germs of life meet under the right conditions. Dennett defines the birthing process as labor and states that as doctors become more educated, labor will be painless for women. She also mentions that when doctors can help make labor painless, individuals will also begin to understand how to control conception. Dennett does not expand on that statement other than to note that providing individuals with information about preventing conception is illegal.

Dennett then discusses menstruation, masturbation, and venereal diseases. She describes menstruation as the flow of blood away from the body when a woman does not have a fetus that requires blood to help it grow. In her discussion of masturbation, Dennett advises her audience not to fear the desire to handle their own sex organs as long as it is not done in excess because then they are depriving their body of the sex secretions it needs later on in life to procreate. Dennett asserts that children should also not fear two venereal diseases, syphilis and gonorrhea. She claims that although those diseases are transmitted from either sexual contact with an infected person or after contact with any bodily fluid of the sick individual, they can be both prevented and cured. Within the pamphlet, Dennett compares the discovery of cures for those diseases with the discovery of the cure for tuberculosis. She mentions that prostitutes spread venereal diseases and that prostitution is something that should be despised. Dennett ends her explanation of the sex side of life with an emphasis on the claim that individuals should only have sex with those they love and if they do not, they will never find happiness.

In 1922 the postmaster of the United States Postal Services warned Dennett that sending her pamphlet through the mail violated the Comstock Act and informed her that the Postal Services would no longer send any mail of hers that contained the pamphlet. Dennett ignored the warning and began to send her pamphlet in sealed envelopes, believing that post office officials would not open them. However, in 1929, the Supreme Court of the United States in Washington, DC, tried her for breaking the Comstock Act and found her guilty, charging her a fine of $300. Dennett refused to pay the fine.

A year later, Dennett appealed her case to the United States Court of Appeals for the Second Circuit in New York, New York, and the appeals judges, Swan, Augustus N. Hand, and Chase, overturned the ruling that Dennett had violated the Comstock Act. Within the case, Dennett’s attorneys argued that Dennett sought to educate her sons when she wrote the original essay and did not intend to arouse lust or be vulgar, key aspects of obscenity. In her pamphlet, Dennett emphasized the importance of sex within marriage and within the boundary of love, and her attorney’s claimed that Dennett’s intentions were to discuss the subject in a reasonable manner. In addition, because Dennett distributed the pamphlets to parents, specifically married women, not children, she placed the authority in the hands of the parents whether or not to expose their children to this information. Ultimately, the appeals judge concluded that Dennett’s original verdict of guilty should be reversed. The appeals judge argued that Dennett did not seek to distribute obscene materials, but rather educational ones and hence she did not violate the Comstock Act.

The trial surrounding The Sex Side of Life contributed to national discussions regarding the legality of obscenity laws. The judge’s ruling in United States v. Dennett overturned the federal courts previous reliance on the Hicklin rule, which stated that an entire material could be obscene on the basis of a few sentences or if it that material could be classified as obscene if they contained elements that aroused their readers. United States v. Dennett emphasized that text cannot be considered obscene without examining the context and intent of the author in writing the text. National discussion of obscenity laws and sex education was furthered by the publicity of Dennett’s trial. The media publicized Dennett’s trial as she was a 57-year-old grandmother being tried for obscenity. That publicity popularized Dennett’s pamphlet, and she started selling in her work in bookstores after her trial. Her pamphlet was later translated into 15 different languages.


  1. Act of the Suppression of Trade in, and Circulation of, Obscene Literature and Articles of Immoral Use, U.S.C. Section 311 (1873).
  2. Chen, Constance. The Sex Side of Life: Mary Ware Dennett’s Pioneering Battle for Birth Control and Sex Education. New York City: The New Press, 1996.
  3. Dennett, Mary W. The Sex Side of Life. Long Island: Mary Ware Dennett, 1919. Mary_Ware_Dennett_The_Sex_Side_of_Life?id=CyHkIEXcnjYC (Accessed May 16, 2016).
  4. Dennett, Mary W. Birth Control Laws: Shall we keep them, change them, or abolish them. New York City: The Grafton Press, 1926.
  5. Engelman, Peter. A History of the Birth Control Movement in America. Santa Barbara: ABC-CLIO, 2011.
  6. Lederer, L. “The Dynamic Side of Life – The Emergence of Mary Coffin Ware Dennett as a Radical Sex Educator.” PhD diss., Rutgers University, 2011.
  7. New York Times “Mrs. Dennett freed in sex booklet case.” New York Times, March 4, 1930.
  8. Siegal, Paul. Communication Law in America: Second Edition. Lanham: Rowman and Littlefield Publishers, Inc, 2008.
  9. United States v. Dennett, 29 F.2d 564 (1930). 13482364592557808136&q=united+state+v+dennett&hl=en& as_sdt=806 (Accessed May 16, 2016).
  10. Weinrib, Laura M. “The Sex Side of Civil Liberties: United States v. Dennett and the Changing Face of Free Speech.” Law and History Review 30 (2012): 325–386.


How to cite

Lakshmeeramya, Malladi, "The Sex Side of Life (1919) by Mary Ware Dennett". Embryo Project Encyclopedia ( ). ISSN: 1940-5030


Arizona State University. School of Life Sciences. Center for Biology and Society. Embryo Project Encyclopedia.

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