This is a scan of a 26-year-old woman, who presented with 20 weeks of amenorrhea. Fetal movements are well perceived by her. She has one healthy living child.

The above images demonstrate a normal uterus with a thin endometrial stripe and normal bilateral ovaries. This was a case of Pseudocyesis. Our patient was very upset to learn that we did not find her pregnancy and did not believe a word of what we told her.

Discussion: Pseudocyesis or phantom pregnancy is a constant source of bewilderment to clinicians even today. It is a condition where a non-pregnant woman believes that she is pregnant and has objective signs of pregnancy. Its exact pathogenetic mechanism is still unknown.

According to one study of 11 patients by Meza, et al ² pseudocyesis was characterized by the following criteria:
1. Secondary amenorrhea [>12 weeks]
2. Two or more symptoms of pregnancy such as nausea, breast tenderness, abdominal distension, weight gain, etc.
3. Conviction of being pregnant and
4. A negative beta-HCG or pelvic ultrasound study.

Pathogenesis: According to Small, et al ^{3, 4} both psychological and neuro-endocrine mechanisms are involved in the development of pseudocyesis. A few of the conditions that may predispose to this kind of psychological disturbance resulting in pseudocyesis include recent pregnancy loss, history of infertility, rigid and orthodox society and cultural rituals that focus on child-bearing role of women and social isolation.

However, in some patients pseudocyesis may be a sign of some underlying organic disease such as systemic lupus erythematosus (SLE) ⁵ and schizophrenia. Patients with an underlying bronchogenic carcinoma may also sometimes, though rarely manifest with pseudocyesis. In these patients, pseudocyesis essentially represents a paraneoplastic syndrome occurring due to elevated levels of ectopic beta-HCG that is produced by the tumor.

Therefore, it should be kept in mind that not all patients presenting with pseudocyesis have pscyological disturbance but a rare few may also have some serious underlying organic disorder.

Imaging and patient management: Ultrasound is usually the only imaging modality that is performed in these patients and it shows a normal endometrial stripe with absence of an intrauterine pregnancy. Blood tests reveal a normal beta-HCG level unless there is ectopic beta-HCG production.
Patient management involves convincing her that she is not pregnant and appropriate psychological counseling. Underlying depression if present may need to be treated with pharmacotherapy.

References:
1. Rosenberg HK, Coleman BG, Croop J, Granowetter L, Evans AE. Pseudocyesis in an adolescent patient. Case report and radiologic analysis. Clin Pediatr (Phila). 1983 Oct; 22(10):708-12.
2. Meza E, Choy J, Villanueva C, Ayala A. Pseudocyesis: clinical and hormonal evaluation. Gynecol Obstet Mex. 1989 Nov; 57:308-10.
3. Starkman MN. Impact of psychodynamic factors on the course and management of patients with pseudocyesis. Obstet Gynecol. 1984 Jul; 64(1):142-5.
4. Small GW. Pseudocyesis: an overview. Can J Psychiatry. 1986 Jun; 31(5):452-7.
5. Hernandez Rodriguez I, Moreno MJ, Morano LE, Benavente JL. Systemic lupus erythematosus presenting as pseudocyesis. Br J Rheumatol. 1994 Apr;33(4):400-2
6. Whelan CI, Stewart DE. Pseudocyesis--a review and report of six cases. Int J Psychiatry Med. 1990; 20(1):97-108.