This is a hypothetical situation to explore an idea. Suppose an employer advertises a fixed-term job with the stipulation that potential employees must disclose any reasons which may interfere with their ability to complete the project.
A female applicant applies for a job and doesn't tell the prospective employer she may be pregnant. The employer gives her the job. The employee later tells the employer she is now pregnant. The employer wants to sack the employee for failure to disclose information that may have affected their decision to employ the applicant. The employee wants to claim discrimination.
Who is in the wrong? The employer for sexual discrimination or the employee for failing to disclose relevant information? What are the arguments from either side?
Not giving the job because she was pregnant is sex discrimination, The employer should not be asking questions that allow then to discriminate and deserves everything they hypothetically get.