Respond to prefers-color-scheme dark in app web views

Follow section front redirects in Spectrum

Enable NLP source in PCS for load testing

Switch off the News Alerts Survey Widget when we have enough responses

Poll to determine if new LUF updates are available

Allows the winning A/B test variant to be turned on without Spectrum deployment

Show infinite scrolling sections in Assembler MultiView

Show option for NLP article summaries in Action Bar

Show NLP summaries collection recirc on article pages

A general feature flag for Recipe Features that aren't yet released

Feature flag for media team features that aren't yet released

Use new Orca video player for preroll plugin in Spectrum

Show the snow tracker (instead of the heat tracker) on Spectrum

Serve seared scallops on a creamy herb sauce for a quick, elegant meal

Seared Scallops With Creamy Herb Sauce

From a forgotten Indian cookbook, a deeply flavored chickpea curry

A college professor wants to use Section 230 against Big Tech

Commerce Department revokes more export licenses to China’s Huawei

Defense think tank MITRE to build AI supercomputer with Nvidia 

Nats go over .500 the hard way by beating the O’s and Corbin Burnes

These Nationals are pretty fun. They’d be more fun with James Wood.

Baseball can crush rookies. Why hasn’t it crushed Trey Lipscomb?

Social Security has to be fixed. But you still need your own savings.

An I bond is now at 4.28 percent. Are they still a good deal?

Use these 6 points to say no to a college you and your kid can’t afford

Dog hit by car loses leg, is adopted by firefighter who helped her

Postal worker finds WWII-era letters, drives 5 hours to deliver them

Strangers help Sesame Street puppeteer after heirloom necklace was stolen

RFK Jr’s ‘history lesson’ on Russia’s invasion of Ukraine flunks the fact test

Biden back in the battleground state of Wisconsin

In court, Stormy Daniels pulled a Trump on Trump 

How Trump’s allies amplify his Truth Social messages to the wider world

In Arizona, election workers trained with deepfakes to prepare for 2024

‘Look at the U.S.A.’: A photographer’s reflection on post-9/11 conflict

In photos: The scene after tornadoes struck Michigan and Oklahoma 

Carolyn Hax: Family pushes siblings to ‘make amends’ after their mother’s death

Miss Manners: I’m offended by a golfer’s skirt choice

Ask Amy: I want to be closer with my brother. He never reaches out to me.

The next global crisis could come from the sun. We should prepare now.

The FTC’s noncompete clause rule goes too far

The crisis Biden and Trump don’t want to deal with

Arrested U.S. soldier was in Russia to pursue girlfriend

Middle East conflict live updates: WHO says health services in south Gaza will run out of fuel in three days

U.S. signals optimism for Gaza cease-fire as Israel moves into Rafah 

Cruise worker charged with stabbing 3 with scissors on ship off Canada

France tries to shed its rude reputation ahead of the Olympics

Don’t be a jerk at the airport: A guide for headphones

The Trump-Biden battle over the 2017 tax cut

That time football legend, rig-driving eligible bachelor Biden was arrested

US-VOTE-POLITICS-ECONOMY-BIDEN

For centuries, women have used the calendar method for getting pregnant (or for avoiding getting pregnant) based on the idea that having sex on or around the days they are ovulating increases their chances of conception.

But what about the "off" days? According to two studies recently published in the journals <a href="http://www.fertstert.org/article/S0015-0282(15)01885-3/abstract">Fertility and Sterility</a> and <a href="http://www.sciencedirect.com/science/article/pii/S0031938415301153">Physiology and Behavior</a>, having more sex, <em>any time</em> may boost fertility.

Tierney Lorenz, a visiting research scientist at the Kinsey Institute at Indiana University, theorizes that sex appears to trigger physiological changes that may be preparing a woman for pregnancy.

In the first study, which involved 30 women, Lorenz and her colleagues found sexually active women experienced greater changes in what are known as "helper T cells," as well as the proteins that T cells use to communicate. In the second, which involved 32 women, the researchers found similar differences in how antibody levels fluctuate between the two groups.

Helper T cells are a key part of the body's immune response, activating cells that defend the body against microbes. Antibodies, or immunoglobulins, are secreted by white blood cells and fight infection from bacteria, viruses and other attackers.

"We're actually seeing the immune system responding to a social behavior: sexual activity," Lorenz said in a statement. "The sexually active women's immune systems were preparing in advance to the mere possibility of pregnancy."

The researchers wrote that their findings appear to show that women's physiology "navigates tradeoffs between reproduction and immunity."

The studies, which involved taking saliva samples and blood samples from the women -- about half of whom were sexually active and half of whom were not -- found that levels of helper T cells fluctuated throughout a women's menstrual cycle. During the luteal phase, which is when the uterine lining thickens in preparation for pregnancy, they found higher levels of type 2 helper T cells in sexually active women than in those who had abstained from sex. During the follicular phase, during which the ovaries' follicles are maturing, researchers found higher levels of type 1 helper T cells.

They found a parallel change in antibodies. During the luteal phase there were higher levels of immunoglobulin G, and during the follicular phase, higher levels of immunoglobulin A.

"The female body needs to navigate a tricky dilemma," Lorenz said. "In order to protect itself, the body needs to defend against foreign invaders. But if it applies that logic to sperm or a fetus, then pregnancy can't occur. The shifts in immunity that women experience may be a response to this problem."

<a href="https://www.washingtonpost.com/news/to-your-health/wp/2015/10/07/neighbors-file-lawsuit-against-autistic-boys-family-alleging-his-behaviors-constitute-a-public-nuisance/">Neighbors file 'extraordinary, unprecedented' public nuisance lawsuit against family of autistic boy</a>

<a href="https://www.washingtonpost.com/news/to-your-health/wp/2015/10/02/the-u-s-recess-predicament-extraordinary-photos-of-what-we-can-learn-from-play-in-other-parts-of-the-world/">The problem with recess in the United States: We get 27 minutes. Finnish kids get 75, Japanese kids even more.</a>

<a href="http://www.washingtonpost.com/sf/national/2015/09/30/brain/">SPECIAL REPORT: Billionaire Paul Allen's quest to build an artificial brain</a>

<em>For more health news, you can sign up for our weekly newsletter <a href="http://wapo.st/1LDkwOZ">here</a>.</em>

Columbia University

Ariana Eunjung Cha is a national reporter. She has previously served as The Post's bureau chief in Shanghai and San Francisco, and as a correspondent in Baghdad.

Ariana Eunjung Cha

The Washington Post

Health Care

Medical Mysteries

Science

Well+Being

Health

prism://prism.query/site,/health&limit=20

The Washington Post health section provides coverage and analysis of health, healthcare, nutrition and fitness news.