Answer:
the pregnant woman and the father of the fetus
Explanation:
According to my research on studies conducted by various medical professionals, I can say that based on the information provided within the question the investigator must obtain consent from the pregnant woman and the father of the fetus. This is because the research and experiment has the probability of affecting the unborn baby and since a baby's health and life is the responsibility of both parents, the investigator needs consent from both of the parents.
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