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

Temporary Penicillin Shortage Could Be Dangerous for Pregnant Women with Syphilis

The development of antibiotics in the 1940s ushered in a new era in which bacterial infections—including syphilis, one of the oldest sexually transmitted infections (STIs)—could be treated or cured. With that came the ability to prevent congenital syphilis, which occurs when a pregnant woman passes the bacteria to her infant. Congenital syphilis can cause miscarriage, stillbirth, severe illness in the infant, and even early infant death. And, as Rewire recently reported, it is on the rise; between 2012 and 2014, there was a 38 percent increase in the rate of congenital syphilis.

The good news is that if a pregnant woman is treated with an antibiotic at least 30 days before giving birth, there is a 98 percent cure rate, meaning her infant would not be born infected. The bad news is that, until next month, there is a shortage of the one antibiotic approved for treating syphilis in pregnant women.

Bicillin L-A, an injectable form of penicillin that is also used to treat other infections such as strep throat, is manufactured by Pfizer. The company said in April that it was experiencing “an unanticipated delay in manufacturing,” and that it would be shipping just 30 percent of the usual supply until July.

Typically, pregnant women are tested for syphilis during their first prenatal visit. If infected, they are treated with three injections of Bicillin L-A. In an attempt to keep these routine “test and treat” efforts going despite the shortage, the Centers for Disease Control and Prevention (CDC) has asked that health-care providers refrain from prescribing Bicillin L-A for any infection other than syphilis if other treatments are available.

Supply issues are unfortunately common in the pharmaceutical industry. NPR explains that generic, injectable drugs—like Bicillin L-A—are particularly susceptible to shortages because they are difficult to make but cheap to purchase, meaning few drug companies manufacture them. If those companies experience a difficulty in manufacturing that forces them to shut down temporarily, such as rust in the equipment or mold in the factory, there is no other supplier to pick up the slack.

Luckily, Pfizer expects to be back to full capacity on Bicillin L-A by July, which will help make sure there are no disruptions to efforts to prevent congenital syphilis. This is particularly important given the number of cases that have been seen in recent years and the seriousness of the outcomes. In 2014, there were 438 nationwide cases of congenital syphilis, which led to 25 stillbirths and eight deaths within 30 days of birth.

Women Want More Sex than Their Male Partners Think

There is an enduring myth that men always want sex and women, well, not so much. It turns out that women in long-term relationships with men want more sex than their partners realize. To determine if perception and reality differed, researchers conducted three studies with couples—44 couples in the first study, 84 in the second, and 101 in the third. All but ten were opposite-sex couples.

Though questions varied according to the study, each participant was asked to keep a diary that recorded some combination of the following factors: their own sexual desire; relationship satisfaction; commitment to their partner; and their perception of their partner’s sexual desire, relationship satisfaction, and commitment. Couples were also asked to keep a log of their sexual activity. Couples in the third study were asked to record how motivated they were to avoid sexual rejection on any given day.

While men in the study did report higher levels of sexual desire than their female partners, what was more striking was that across all three studies men consistently underestimated their partner’s desire. The researchers are not sure why men’s perceptions were so frequently off but they have at least two theories.

First, as Amy Muise, the lead author on the study, told Fusion via email it might be about avoiding complacency: “We don’t know exactly what men do when they underperceive, but it’s possible that this keeps them from becoming lazy about maintaining their partner’s interest.”

Alternatively, men may perceive less desire from their partners as a way to avoid sexual rejection. This is supported by the additional finding that men were particularly likely to underestimate their partner’s desire on days when they felt ill-equipped to handle rejection.

Of course, it could just be that men have been trained by every television show, movie, and magazine to believe that women just don’t want sex as much as they do.

No matter where the misperception comes from, the results of this study once again point out how important it is for couples to communicate openly and honestly about what they want and how often they want it.

Bud Light Ad Celebrates Same-Sex Marriage

While Budweiser ads of the past seem to have mostly celebrated bikini-clad women and Clydesdale horses, a new ad released in honor of LGBT Pride Month takes a big turn for the beer company. The ad depicts scenes of a wedding and features actor Seth Rogan and comedienne Amy Schumer leading a beer-bottle toast to the groom and the groom.

The company said in a press release: “June is the height of wedding season, and it is also LGBT Pride [M]onth in America. That’s why right now is the time to spark a national conversation by celebrating every kind of wedding—and everyone’s right to marry whoever they choose.”

The ad was released in partnership with Ellen DeGeneres and first appeared on her social media channels. The company will continue to air the ad on social media and plans a primetime television airing as well.

Gwyneth Paltrow’s Goop Suggests a Gold-Plated Vibrator

You may remember when Goop, the lifestyle site launched by Oscar-winning actress Gwyneth Paltrow, suggested steam-cleaning vaginas with the herb multwort, a practice that was roundly criticized by experts as unnecessary (the vagina cleans itself) and potentially dangerous (steam is hot). Goop made news again recently with a sexual-health suggestion that may be good for vaginas, but not so great for bank accounts.

Suggested on the website’s list of favorite sex toys was the LELO INEZ, a 24-karat gold vibrator that costs $15,000. Other pricey toys included a whip for $535 and a vibrating necklace for $395.

We here at This Week in Sex are all for sex toys. But we want to assure you that there a lot of good sex toys out there that won’t break the bank. You should be able to find some reliable toys for between $35 and $65 and even less, if you want to visit a local pharmacy and find vibrating rings (which, as an added bonus, are often packaged with a condom).