Yahoo Is 20: The 20 Biggest Moments in Parenting in the Last 20 Years

Parenthood has evolved a lot over the past two decades — from breastfeeding to stay-at-home fathers to baby bump obsession to ‘Frozen’ mania. In honor of Yahoo's 20th anniversary, here are the people, ideas, and events that have shaped the parenthood experience, courtesy of Yahoo Parenting.

Babies start sleeping on their backs: The Safe-to-Sleep Campaign (formally known as “Back to Sleep”) is publicized in 1994 by the American Academy of Pediatrics (AAP) to encourage parents to place babies to sleep on their backs (not stomachs). As a result, the SIDS rate plummets.

Baby boom: There is a increase in births — 140 percent — from 1996 to 2004, as a result of couples using in vitro fertilization (IVF) after the technology was introduced in 1992.

Defense of Marriage Act (DOMA) was signed into law: In a strike against gay families, President Clinton signs into law the Defense of Marriage Act (DOMA) in 1996, federally defining marriage as between a man and a woman. On the bright side, the act inspires two decades of activism surrounding LGBT equality, leading to the legalization of same-sex marriage in 36 states (and counting) and legalized joint adoption by gay couples in 33 states.

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BPA anxiety begins: A study of mice conducted in 1997 by biologist Frederick vom Saal shows that exposure to the compound Bisphenol A (BPA) during pregnancy potentially causes developmental disorders. His work triggers many studies on the topic and a national debate, causing mothers to question the safety of baby bottles and sippy cups.

Breastfeeding guidelines are revised: In 1997, the AAP updates its policy on breastfeeding, recommending for the first time that infants be exclusively breastfed for six months, that nursing continue for 12 months, “and thereafter for as long as mutually desired.”

Diaper changing gets a makeover: Playtex Products sells the Diaper Genie, a scented diaper disposal system, in 1999.

“Losing” baby weight becomes easier: In 2000, body shape wear called Spanx are sold in Neiman Marcus and Saks Fifth Avenue department stores, to the joy of postpartum women everywhere.

Dads get to bond more with their babies: In 2002, California becomes the first U.S. state to guarantee six weeks of paid leave for both mothers and fathers.

‘Bump watch’ begins: Canadian editor Bonnie Fuller is the editor-in-chief of US Weekly magazine and coins the phrase “Bump watch” in 2002.

We’re introduced to attachment parenting: Pediatrician Bill Sears publishes “The Baby Book” in 2003, introducing the concept of “Attachment parenting” (extended breast-feeding, co-sleeping, and baby slings).

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Babies get shushed to sleep: Pediatrician Harvey Karp publishes the 2003 book, “The Happiest Baby on the Block” outlining his “5 S’s theory” for soothing cranky babies.

Foreign adoption rates skyrocket: Actress Angelina Jolie adopts an Ethiopian orphan named Zahara in 2005 and parents begin seeking orphans from Ethiopia in droves. 

Parents stand up for sleep: Writer Adam Mansbach published the 2007 book “Go the F*** to Sleep,” a children’s book for adults about a child who refuses to sleep.

Home births get publicized: Talk show host Ricki Lake’s 2008 documentary “The Business of Being Born” debuts, which critiqued the birthing system in America.

Baby food gets convenient: Baby food moves from jars to squeezable pouches in 2008. The concept paved the way for “free-range parenting,” the idea that parenting should be more flexible in all areas.

Women delay motherhood: In 2010, The Pew Research Center reports that women are having babies later in life. (The average age for U.S. mothers who had their first baby in 2008 was 25, a year older than the average first-time mother in 1990).

Women start pumping breast milk at work: President Obama signs the Affordable Care Act (ACA), which requires companies (with more than 50 employees) to provide reasonable break time for women to pump breast milk and guaranteew them private rooms to access their breast milk.

The rise of the stay-at-home dad: In 1989 there were 1.1 million SAHDs and in 2010, there were 2.2 million SAHDs, according to a Pew Research Center. The trend peaked when the recession (a.k.a., “the man-cession”) officially ended in 2009.

Prenatal testing for down syndrome (among other disorders) is available: In late 2011 and early 2012, the MaterniT21 Plus test is offered to doctors to test pregnant women for chromosomal defects in their babies.

A tragic shooting occurs at Sandy Hook Elementary School: 2012: A gunman fatally shoots 20 children and six adults at Sandy Hook Elementary School in Connecticut. The incident prompts national debates about gun control and renewed laws.

We ‘Lean In’: 2013: Facebook COO Sheryl Sandberg publishes “Lean In,” a must-read book that empowers women to succeed at work.

'Frozen' mania kicks off: The Walt Disney animated movie Frozen is released in 2013, accumulating $1.3 billion in worldwide box office revenue and giving way to mass tween obsession.

Employers pay for egg freezing: In 2014, Facebook and Apple offer egg-freezing benefits to employees.

The vaccination wars begin: On the heels of a worldwide infectious diseases epidemic and a long-standing battle between immunization proponents and “anti-vaxxers,” in 2015, the Centers for Disease Control (CDC) updates its vaccination schedule for children.

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