Introduction
The claim is a bit more complex than presented by the question, which is an extract of a particular bullet point in a larger set of "things that could go wrong" going to a Crisis Pregnancy Centers, according to Planned Parenthood.
In particular the OP points to the main claim of bias/wrongdoing of same of the CPCs and a particular claimed risk that they could lie about the results of pregnancy tests. I'm addressing both claims in the following paragraphs.
A note of caution. Medical and scientific facts are taken as representing our best knowledge in the rest of the answer. The following paragraphs will merely concentrate on ascertaining whether some CPCs committed certain actions. If you disagree with the mainstream scientific position on contraception, pregnancy tests and abortion you are probably better off not proceeding.
First Claim
They have a history of giving women wrong, biased information to scare them into not having abortions
This is evidently true and even a cursory look using google returns dozens of studies (some with the US government imprimatur) showing that they do.
Wrong info about consequences
According to The Star, CPCs offer false medical information about the consequences of abortion: they overstate (or completely make up) emotional trauma, breast cancer and future fertility problems.
Wrong info about consequences
According to Abortion misinformation from crisis pregnancy centers in North Carolina, a peer-reviewed article,
Many crisis pregnancy centers give inaccurate medical information regarding the risks of abortion. Overstating risks stigmatizes abortion, seeks to intimidate women and is unethical.
Wrong info about consequences, manipulation
According to a study by the University of Chicago some have deceptive practices:
CPCs continue to provide limited resources, inaccurate
information and biased counseling to women seeking prompt
and reliable reproductive guidance and care. While the
services they provide may be appropriate for the needs of
some women, the delays and misinformation at many of these
centers can undermine the health and well-being of women.
Wrong info about facts
According to the Guttmacher Institute, Misinformed Consent: The Medical Accuracy of State-Developed Abortion Counseling Materials:
A pregnant teenager who relied on the information from these federally funded centers would make her decision about whether to give birth or terminate her pregnancy based on erroneous facts and misinformation.
Second Claim
may tell you that you are not pregnant even if you are. This may fool you into continuing your pregnancy without knowing it. If your decision is delayed, it could make abortion more risky. It could also keep you from getting early prenatal care.
A bit harder to find in the dozens of reports available, but there's very strong evidence that there is a concrete risk they do lie, manipulate and try to delay patients using pregnancy tests.
Manipulation
According to an independent journalistic report on the Huffington Post
I could hear two employees whispering before entering my room, plotting strategies to reveal the test results and best manipulate my reaction.
So there's at least a real example of a CPC manipulating how (positive) pregnancy test results are revealed.
Wrong information about tests
A pro-choice group presented a referenced study of CPCs in Virginia and found that:
Several CPCs told our investigators of the need to "medically confirm a pregnancy"
before even considering abortion, and many stressed the importance of obtaining a "professional" pregnancy test – despite using common urine tests widely available in stores. One investigator was told to visit the center for a pregnancy test because "the pregnancy tests we use are extra sensitive and better than the average pregnancy tests."
So, above, they are saying to a woman who has done a test by herself and found it positive to disregard the result and do one of theirs.
Wrong information about tests
They have been caught bold face lying about pregnancy tests by the New York Times
All three centers advertise "free pregnancy tests." Since the City Health Department levied its fines, which ranged from $750 to $4,000, it is unclear whether tests are still being processed on the premises. At the time of Ms. Weinstock's visit, she said, she was told that urine and blood tests were "identical" and that a urine sample did not need to be taken the first thing in the morning. Both pieces of information are incorrect.
Delaying tactics
According to a Pro-Choice research paper:
CPCs employ tactics designed to delay and even harass or intimidate women from having abortions. For example, CPCs have been known to extend the waiting period for pregnancy test results to expose women to their anti-choice or religious propaganda
Delaying tactics
According to another pro choice research:
Our investigators found that medical services were often used to lure women into the centers or to delay abortion services. All centers visited offered free pregnancy testing. This is a principal strategy used to entice women into the centers. Unfortunately, CPCs used this seemingly benign service as an opportunity to dissuade women from
abortion.
Caveats
I've ignored the "may" in the second claim even though they clearly present this as a possibility and not a certainty
Some resources are pro-choice, and they were chosen because:
- they presented a clear argument
- it was published, possibly reviewed and always well referenced
- I presented at least another independent, not pro-life reference for the same claim
There are very many resources on this topic, if anyone has patience to find more example they should free to add them to this answer.