Primary hyperparathyroidism (PHPT) is a rare endocrine disease, but it is the most common cause of hypercalcemia in non-pregnant women. In the scientific literature and clinical practice of an obstetrician-gynecologist and endocrinologist, planning, pregnancy and the birth of a healthy child in a woman with PHPT are presented in rare cases and undoubtedly arouse scientific and practical interest. A clinical case from the practice of a gynecologist and endocrinologist of a patient who became pregnant against the background of hyperparathyroidism is presented. The history and clinical picture of the disease, the data of hormonal and instrumental methods of examination, and the treatment are described. A patient with hyperparathyroidism and pregnancy was observed by an endocrinologist and a gynecologist throughout the entire gestational period, the necessary laboratory and instrumental methods of examination, constant monitoring of the clinical condition, and correction of drug therapy were carried out in dynamics. Currently, there is no consensus on the treatment of PHPT during pregnancy, and an individualized approach to therapy is required for pregnant women with PHPT. The management of pregnancy in women with PHPT depends on the severity of symptoms, gestational age at the time of manifestation, age, concomitant diseases and complications. In women of childbearing potential with PHPT detected before pregnancy, it is essential to provide preconception counseling and radical surgery based on the underlying etiology of PHPT before conception. For optimal maternal and fetal outcomes, a multidisciplinary approach is recommended with close collaboration between an endocrinologist, obstetrician, and pediatrician. Special cases (parathyroid cancer, syndromic forms) should be accompanied by an individual treatment plan in a specialized endocrine department. The management of PHPT during pregnancy should be based on gestational age, severity of hypercalcemia, and the balance of risk and benefit to the mother and fetus.