This Week in Health: Are breast-fed infants trying to prevent mom from having another baby?

Woman breastfeeding an infant
Are babies who wake up for middle-of-the-night feedings trying to prolong the birth of a sibling with whom they’d have to compete?
Credit: Thinkstock

Are breast-fed infants trying to prevent mom from having another baby?

Theory: The act of breast-feeding not only brings mom and baby closer together – it also serves as a natural form of birth control. The same hormones that produce milk in nursing women also suppress the hormones that trigger ovulation. The phenomenon, known as lactational amenorrhea, can be up to 98 percent effective in preventing pregnancy if a woman breastfeeds every two to three hours.

But are babies who wake up for middle-of-the-night feedings trying to prolong the birth of a sibling with whom they’d have to compete? Some experts say yes. “It’s an evolutionary response, not a conscious motivation,” said David Haig, a professor in the Department of Organismic and Evolutionary Biology at Harvard University.

Significance: “The suggestion is that babies that wake and suckle in the night tend to have longer time spans in between the birth of a sibling, which is linked to longer survival,” said Haig. Researchers believe that the benefits of delaying ovulation are substantial enough to have triggered a real evolutionary response. Even today, where reliable contraceptives are accessible, many newborns still wake to breastfeed every two hours. The theory suggests that babies begin tapering off their feedings when it’s safe for mom to resume ovulation.

Study shows not all fish oils created equal

Location of study: U.S.

Study targets: 30 fish oil supplements on the market

Results: A recent report of various fish oil supplements found four out of 30 products to have quality problems. A handful of these products, some of which are marketed for children, lacked key omega-3 ingredients advertised on the label. One product failed to list all of its ingredients, while another popular product that boasts high levels of omega-3s actually only contained small amounts. “We found that more than 10 percent of the 30 products tested had a quality issue, such as less EPA or DHA than claimed or an incomplete list of ingredients,” said Dr. Tod Cooperman, president of ConsumerLab.com.

Significance: If you have the choice of eating fish twice a week or taking a supplement, Cooperman says there are more benefits to eating fish. But for people who don’t eat fish, finding a good supplement can be worthwhile. When shopping for a fish oil supplement, Cooperman suggests checking out the Supplement Facts label on the bottle to make sure the product actually states how much EPA and DHA is in it. “You can actually get a high-quality fish oil supplement for as little as a few cents a day,” he said.

Ovarian cancer risk linked to irregular periods

Location of study: U.S.

Study subjects: Over 15,000 pregnant women

Results: The results from a 50-year study suggest that women who have irregular periods may be 2.4 times more likely to develop ovarian cancer. The risk appears to be even higher for women with a family history of the disease in a first-degree relative. Women whose cycles lasted longer than 35 days were particularly at risk. Researchers speculate that a hormonal imbalance in the ovaries known as polycystic ovarian syndrome might be responsible for this increased cancer risk.

Significance: Ovarian cancer, while rare, is the most deadly reproductive cancer in women. There are currently no screenings in place for early diagnosis, which means that the majority of women who get it don’t know until it’s too late. Researchers say the study’s findings are not meant to alarm women who have irregular periods. The increased average risk is still small because of how rare the cancer is. Even so, they hope that by better understanding how irregular cycles are correlated with ovarian cancer, experts might someday find a way to prevent the disease – or at least reduce mortality when it does occur.

Black vegetarians may be less likely to develop heart disease

Location of study: U.S.

Study subjects: Over 26,000 black Seventh-day Adventists

Results: The Seventh-day Adventist church promotes healthy lifestyle choices, including a vegetarian diet rich in fruit, whole grains and nuts. Consuming alcohol, smoking cigarettes or taking mind-altering drugs are also discouraged. A recent study compared black Seventh-day Adventists who are vegetarians to those who eat meat. According to the findings, the vegetarians are at lower risk for heart disease.

Significance: The benefits of a vegetarian diet among this group appear to be multilayered. The rates of hypertension, diabetes, blood pressure and cholesterol were all significantly better among this group. The findings are especially significant as African Americans are at particularly high risk for cardiovascular disease. The study represents one of the largest to look at heart health in this population.

Content provided by ZipTrials, a trusted source for the most up-to-date medical news and trending health stories.



News
Entertainment
Sports
Lifestyle
Local

Brooklyn man charged in roommate's stabbing death

A Brooklyn man accused of violently stabbing his roommate to death on Monday is in police custody and faces murder charges.

International

Dinosaurs could have survived asteroid strike

It turns out there is a good and a bad time for the planet to be hit by a meteor, and dinosaurs were just unlucky.…

National

OkCupid admits to Facebook-style experimenting on customers

By Sarah McBrideSAN FRANCISCO (Reuters) - OkCupid, a top U.S. matchmaking website, intentionally mismatched users to test its technology, the IAC/InterActive Corp service said on…

Local

MTA fares still increasing 4 percent in newly…

The agency said the 4 percent increases, previously announced in December, will remain steady even as the MTA deals with increasing labor costs.

Movies

Interview: Brendan Gleeson on the way 'Calvary' depicts…

Brendan Gleeson talks about how his new film "Calvary" began over drinks and how his character here is the opposite of the lead in "The Guard."

Movies

'Get on Up' producer Mick Jagger on the…

Mick Jagger, a producer on the James Brown biopic "Get on Up," talks about the time had to tell the singer some bad news and his favorite JB record.

Television

'Glee' star Lea Michele to appear on 'Sons…

"Glee" star Lea Michele has been confirmed as a guest star in the final season of "Sons of Anarchy."

Television

TV watch list, Monday, July 28: 'The Bachelorette'…

See Andi Dorfman make her big choice on tonight's 'Bachelorette' finale.

MLB

Angelo Cataldi: Ryan Howard deserves better from Phillies

Just last week, Ryan Howard endured the embarrassment of a benching that was inevitable, and yet still shocking.

NFL

Larry Donnell has inside track in Giants tight…

Little-known Larry Donnell of Grambling State currently has the inside track, as the second-year player has received the bulk of the first-team reps.

NFL

Computer to Jets: Start Michael Vick over Geno…

Jets general manager John Idzik says the choice of who starts between second-year quarterback Geno Smith and veteran Michael Vick will be a “Jets decision.”

MLB

Yankees looking to trade for Josh Willingham: Report

CBS Sports’ Jon Heyman reported Sunday the Yankees are interested in Twins outfielder Josh Willingham.

Travel

Glasgow: Hey, hey, the gangs aren't here

This European city has done a good job getting rid of its more violent residents and revitalizing with artists.

Education

Babson College tops list of best colleges for…

Money magazine has just released its inaugural list of "The Best Colleges for Your Money" -- and the answers have surprised many. Babson College, which…

Education

NYC teens learn how to develop apps during…

Through a program sponsored by CampInteractive, the high schoolers designed their own community-focused apps.

Tech

The Ministry of Silly Walks app is both…

Monty Python have dug into their back catalogue for cash-ins once more, but with the Ministry of Silly Walks app, they've made something that's fun too.