One claims the group conned the government when it applied for and got a federal grant of $6 million over three years.
Another is linking it to the sinister and long-discredited science of eugenics.
Saskatchewan MP Maurice Vellacott says the federation was deceitful in claiming that the money would only go to countries where abortion is illegal.
Alberta MP Leon Benoit wants to condemn the foundation over an award named for Margaret Sanger.
Sanger was a pioneer in planned parenthood who embraced a type of eugenics.
Saskatoon MP Brad Trost started the ball rolling earlier this week with a web post condemning the decision to fund the international family-planning group.
While the Prime Minister's Office is adamant that abortion is not an issue for the Conservative government, it still seems to be a touchy subject for backbenchers.
The Planned Parenthood grant is a case in point.
Trost said in his web post that the government's claim that the money would be used in countries that bar abortion is "hair-splitting."
Vellacott said the federation is "trying to dupe" the government over abortion.
"Even in those countries where abortion is technically illegal, it's naive to think that Canadian tax dollars are not being used to promote abortion," he said in a news release.
Benoit has put a motion on the order paper asking the House of Commons to condemn the International Planned Parenthood Federation for the annual Margaret Sanger Award because "part of Margaret Sanger's philosophy constitutes eugenics."
The award is actually presented by the Planned Parenthood Federation of America to recognize "leadership, excellence, and outstanding contributions to the reproductive health and rights movement."
The eugenics movement flourished in the early part of the 20th century. It argued for improving the population by controlled breeding. It was embraced by the Nazis in Germany and was cited in support of forced sterilization in some countries, including Canada.
Sanger espoused a version of eugenics.
Note to readers: This is a corrected story. An earlier version said two more Saskatchewan MPs were taking swipes at Planned Parenthood. Benoit is from Alberta.