Over the next several weeks, the protagonist continues to see Beauplaisir in the guise of both Fantomina and the Widow Bloomer, but she is bored by the now unenthusiastic encounters. This pattern is interrupted by two surprising events. First, the protagonist’s mother arrives in the city, having heard rumors of her daughter’s reckless behavior. She has no idea of the extent of what the protagonist has done, but is sufficiently concerned so as to begin to limit her daughter’s freedoms. More importantly, the protagonist discovers that she is pregnant. It is difficult for her to hide this condition from her mother, but she manages to do so for a time. Since her mother plans to send her back to the country anyways, her plan is to wait until she leaves the city, then slip away and discreetly give birth in secret.
Unfortunately for the protagonist, she goes into labor during a court ball. She is clearly in pain, but everyone at the ball assumes she has been abruptly taken ill, including her mother. She is rushed back home, where her mother summons a doctor. The doctor quickly informs the protagonist’s mother what the situation actually is; the mother is horrified and outraged. She demands that the protagonist reveal the father of her child, which is something the protagonist tries to avoid doing. The mother, however, insists that she will not call a midwife to help the protagonist unless she first reveals her lover. Afraid and in pain, she names Beauplaisir as the father.
The mother immediately sends for a midwife and also sends a message for Beauplaisir to come and see her. He promptly arrives, confused as to why this aristocratic woman has summoned him. When she accuses him of having impregnated her daughter, he denies it, insisting that he has had only brief interactions with her during formal social occasions. The mother is more infuriated than ever, and drags Beauplaisir into the room where the protagonist is resting, having just given birth to a baby girl. Humiliated and horrified, the protagonist reveals the whole story of how she deceived and tricked Beauplaisir repeatedly, so that, while he is indeed the father of her child, he is innocent of any deliberate intent to dishonor a respectable lady.
After listening in astonishment, the mother admits that she can no longer demand that Beauplaisir marry her daughter, which is what she had initially planned to insist on. She asks only that he not publicly reveal the scandal to others. He agrees to keep the secret and also offers to raise his daughter, but both the protagonist and her mother reject this offer. Beauplaisir leaves the house in a state of deep confusion and shock. For a time, he continues to visit to check in on the protagonist’s health, but when her mother becomes concerned that these visits will lead to the two renewing their affair, she puts a stop to them. As soon as the protagonist has recovered, she is sent to a convent in France.
In the novel's final section, the protagonist's ruse is interrupted by two reassertions of authority, one social and the other biological. The abrupt appearance of her mother signals the return to a more socially conventional dynamic in which the protagonist's behavior would be closely scrutinized and monitored by parental authority figures so as to maintain her reputation and value on the marriage market. From the very beginning, the protagonist's ability to do whatever she wants and pursue her desires has been linked to the lack of parental supervision; when her mother appears, this freedom and autonomy quickly disappears. While her mother clearly does not know the extent of the liberties the protagonist has taken, she already has some suspicions. This suggests that the protagonist might not have been quite as discreet as she believes.
Pregnancy is the second and more serious consequence to the freedoms the protagonist has enjoyed. In an era where medical knowledge of effective contraception was very limited, and where young women would have been sheltered from even the most basic biological knowledge, unintentional pregnancy would have been a common consequence of sexual activity. While the protagonist's careful planning and foresight has helped her to avoid many of the social consequences of illicit sexual activity, she has not been able to avoid the biological one, and in a sense it seems that her body finally triumphs over her mind. As Charles Hinnant explains, "the deceptions expose an insoluble conflict between the dual imperatives of pleasure and procreation. Fantomina seems blissfully (and most implausibly) unaware of the obvious risk to which her successive disguises and liaisons with Beauplaisir expose her" (p. 406), that risk being pregnancy. At first, however, she seems confident in her ability to solve this problem just as she has resolved many others. Having the child in secret and presumably arranging to have it adopted would have been the most common strategy for aristocratic women trying to hide illegitimate pregnancies. With her intelligence and wealth, it seems possible that the protagonist might be able to successfully execute this plan.
Pregnancy, especially before modern medicine, makes her physically vulnerable, and ultimately undermines the agency she has exerted throughout the novel. When she goes into labor, she is in too much pain to be able to conceal it. For the first time, her ability to disguise herself fails her. When her mother realizes that she is in labor and becomes determined to find out the identity of the father, the physical pain of childbirth also finally breaks the protagonist's secrecy. The mother coldly and ruthlessly exploits this suffering to her own end, but is also behaving shrewdly: she hopes that by confronting the father, she can shame him into marrying her daughter, thereby concealing the affair and legitimizing the child. It seems probable that the protagonist may have inherited her quick-thinking and adaptability from her mother.
The mother's success at obtaining Beauplaisir's identity results in the novel's climax, at which the protagonist is finally forced to reveal her deception. She has to endure the shame of admitting her scandalous behavior, and of surrendering control. Beauplaisir's reaction is far more measured than might be expected, given how much he has been deceived. He does not lash out, and he offers to provide for his newborn daughter. More strikingly still, he continues to visit regularly and inquire about the protagonist. This gesture suggests a sincere and ongoing affection for her in spite of all the lies. Indeed, it may indicate that Beauplaisir finds the possibility of one woman possessing a multi-faceted identity, a vivid sexuality, and keen intelligence to be attractive.
However, the forces of social normativity and a return to patriarchal culture exemplified in the protagonist's mother serve to punish her for her transgressions. For Haywood's primarily English, Protestant readership, the prospect of being sent to a convent in France would have been very grim. Catholic cultures were perceived as more repressive and focused on strictly curtailing a woman's freedoms; thus, the protagonist can be assumed to be being sent off to live out her days in isolation, with no freedom or further sexual adventures in store. Moreover, she will not even be able to redeem herself by a legitimate marriage and family. While not clearly explained, it seems likely that the protagonist will also be estranged from her infant daughter.
Thus, for the three generations of women assembled at the end of the story, little seems to have changed. The protagonist has boldly challenged the status quo, and highlighted the ways in which a woman might occupy a complex identity. She is ultimately not successful in maintaining this position, and ends up ironically with far fewer freedoms than she would have possessed as a respectably married woman in England. Whether the ending should be read as a punishment for her transgressions or as an indictment of how society conspires to repress women is ambiguous. What is clear is that the protagonist's innocent curiosity costs her a high price.