Consumers are seeing a lot more advertisements with the growth of advertising on Amazon's marketplace. Major brands like Johnson & Johnson are paying Amazon big bucks to place those sponsored product ads in baby registries.

U.S. advertisers will spend $4.61 billion using Amazon’s ad platform this year -- up 144.5% from 2017, according to eMarketer. 

Some mothers are complaining that Amazon's sponsored ads in its baby registry look too similar to the product listings, a challenge that Google had to address and change in its search engine results not too long ago.

The ads look identical to the rest of the listed products in the registry for the exception of a small gray "Sponsored" tag to identify the advertisement. Too often consumers click on sponsored ads by mistake. 

Unfortunately, that "Sponsored" tag isn't enough to identify an advertisements, because friends and family who buy from the mother's registry mistakenly click on those ads and make a purchase of the item, which isn't on the mother's list. 

A 28-year-old health-care analyst from Fredericksburg, Virginia called the sponsored ads “very sneaky," according to The Wall Street Journal.

When new parents create a baby registry, Amazon inserts three sponsored product ads, but the marketplace told the WSJ it plans to phase out the sponsored listings. It's not clear if those will phase out solely in the baby registry or across its marketplace. 

Similar to Google's tests in search results, marketers can expect to see Amazon running very similar tests across its marketplace. 

On Twitter, Amazon is not the only marketplace or site to receive negative reviews for littering the site with sponsored ads. Twitter users also complain about Instagram and Facebook.