This Week in Sex is a weekly summary of news and research related to sexual behavior, sexuality education, contraception, STIs, and more.

Sex Once a Week Is the Happiest Number for Long-Term Couples

It is not startling that there is a correlation between how often a person has sex and how happy they are, but we might be surprised by how much sex is just right for most couples. Results from a new study published in the journal Social Psychology and Personality Science, found that for long-term couples, once-a-week sex appears to be the perfect number for long-term couples.

Researchers looked at data from 25,510 people in the United States, ages 18 to 89, from the years 1996 and 1998. About two-thirds of them were either married or in a romantic relationship. More sex correlated with more happiness for those who were married or in long-term relationships, but this correlation was not statistically significant for single people.

The interesting thing about the results for those in relationships is that the correlation peaked at having sex one time per week. Anne Muise, the lead researcher on the study, told NPR in an email, “This showed a linear association between sex and happiness up to a frequency of once a week, but at higher frequencies there is no longer an association. Therefore it is not necessary, on average, for couples to aim to engage in sex as frequently as possible.”

The correlation held steady regardless of gender, age, or length of relationship. Moreover, Muise and her colleagues checked their results to make sure the data was not too old (an online survey of 355 current couples confirmed the once-a-week sweet spot) and that it made sense (analysis of a different national data set found frequency of sex counts for only 7 percent of the relationship between relationship satisfaction and happiness).

The takeaway from the study, according to Muise: “[It’s] important to maintain a sexual connection with a romantic partner, but it is also important to have realistic expectations for one’s sex life (given that many couples are busy with work and family responsibilities.)”

Cleveland Clinic Announces Uterine Transplant Study

Researchers at the Cleveland Clinic announced last week that they are looking to accept ten women into a study testing the possibility of using uterine transplants for women with uterine factor infertility (UFI), which includes those who were born without a uterus, lost their uterus, or have one that does not function.

As Rewire has reported, attempts at uterine transplants have been done in other countries with varying levels of success. In September of 2014, the first baby gestated in a transplanted uterus was born to an unidentified Swedish woman. The mother was part of a study of nine women who received transplanted uteruses, however, and not all of them fared as well. At least two of them had to have their donated uteruses removed.

For the new study, researchers at the Cleveland Clinic began screening women in September, putting them through medical and psychological evaluations to determine suitability. A chosen patient will first have eggs retrieved from her own ovaries. The eggs will be fertilized with sperm, and the resulting embryos will be frozen. Researchers will then search for a donor uterus from a deceased donor—other studies have used live donors, such as older relatives—and transplant the uterus within six to eight hours of the donor’s death. The woman will be put on anti-rejection medications and monitored for a year while the transplanted uterus fully heals. Then the researchers will attempt to implant the frozen embryos. If she becomes pregnant, she will be monitored by a team of high-risk obstetricians through delivery.

After one or two pregnancies, the woman will have a hysterectomy to remove the transplanted uterus and can then stop the anti-rejection drugs. The researchers note that the risk of the transplant should not be higher than comparable procedures, and note that it is intended to be temporary.

According the New York Times, eight women have started the screening process. One of them, a 26-year-old woman who has two adopted children, traveled more than 1,000 miles in hopes of being including in the trial. She told the Times: “I crave that experience. I want the morning sickness, the backaches, the feet swelling. I want to feel the baby move. That is something I’ve wanted for as long as I can remember.”

Mississippi Teacher Reportedly Suspended Over Condom Demonstration in Her Class

An English teacher in Mississippi has reportedly been placed on leave after a student in her class demonstrated to peers how to use condom. The story came to light as a result of a Change.org petition to reinstate the teacher, which garnered more than 2,000 signatures.

According to the petition, a student in Sherre Ferguson’s Honors English class at Starkville High School used her career presentation to discuss her goal of becoming a sexologist. The petition, seemingly written by family members of the student, says the student took the project seriously. The presentation was reportedly not graphic, but the student did demonstrate to her peers how to use a condom with the aid of a cucumber.

The school apparently became aware of this when the student posted a video of her presentation taken by a friend to Facebook. According to the petition, administrators felt that allowing a student to present on this topic was inappropriate and placed Ferguson on leave as a result.

A Starkville-Oktibbeha Consolidated School District Board of Trustees member confirmed the presentation to the Columbus Dispatch on Wednesday and said that the school had launched an investigation into whether the district’s sex education policy was violated. The district, however, has declined to identify the teacher or the student and has also declined to say whether any disciplinary action has been taken.

As of November 20, the petition had been updated to say that Ferguson would “be returning to the classroom.”

“This was all we wanted to see happen. We felt terrible that anything we might have supported would have harmed a cherished teacher,” the petition’s creators wrote in the update. “We are so pleased that the school administration values their faculty! We want to thank everyone for their support and are proud of our Yellow Jackets!”

Mississippi laws on sexuality education are very strict. Schools are required to teach either an “abstinence only” or “abstinence plus” program. Students must be separated by gender for these classes. Instruction may include discussion of condoms and contraceptives, so long as such discussions include “a factual presentation of the risks and failure rates.” Condom demonstrations, though, are expressly forbidden by the law.

It is unclear whether the law extends outside of sex education classes and whether it applies to student demonstrations. Either way, many educators believe such restrictive sex education laws are bad for students. Jesseca Boyer, the interim president of the Sexuality Information and Education Council of the United States told Rewire in an email, “Knowing how to use a condom correctly is an essential tool to lifelong sexual health. Mississippi’s prohibitive law prevents students from learning how to make empowered and healthy decisions.”