International Journal of Basic & Clinical Pharmacology | December 2021 | Vol 10 | Issue 12 Page 1410 International Journal of Basic & Clinical Pharmacology Olaleye AA et al. Int J Basic Clin Pharmacol. 2021 Dec;10(12):1410-1413 http://www.ijbcp.com pISSN 2319-2003 | eISSN 2279-0780 Case Report Heterotropic pregnancy: a common masquerade than ever thought? Ayodele A. Olaleye*, Boniface N. Ejikeme, Eziaha E. Okeke, Nwabunike E. S. Ede, Bartholomew I. Olinya, Charles N. Edene, John C. Obasi, Emmanuel O. Onyekelu, Amuchechukwu V. Nwafor INTRODUCTION Heterotopic pregnancy is the coexistence of living or dead intrauterine pregnancy, single or multiple, and extra-uterine pregnancy located in the oviduct, ovary, uterine cornua, cervix or rarely peritoneal cavity. 1 More than 90% of ectopic pregnancies are localized in the fallopian tubes. Heterotropic pregnancy is relatively uncommon in spontaneous conception with 1 in 30,000 cases reported, the incidence of heterotopic pregnancy increases to 1 in 3900 when conception is enhanced with various assisted reproduction techniques (ART) including in vitro fertilization, super ovulation, and intrauterine insemination. 2,3 Heterotropic pregnancy has also been reported with clomiphene citrate ovulation induction. 4 However, with rising incidence of undiagnosed or poorly treated pelvic inflammatory disease in low resource settings, the incidence of heterotropic pregnancy may be on the rise. Chlamydia infections are characterized by a high proportion of asymptomatic infections (up to 70% in women) and has been associated with increased incidence of pelvic inflammatory disease and increase risk of ectopic pregnancy. 5,6 The risk factors for heterotropic pregnancy includes, assisted reproductive technology, tubal damage (by DOI: https://dx.doi.org/10.18203/2319-2003.ijbcp20214508 Department of Obstetrics and Gynecology, Alex Ekwueme Federal University Teaching Hospital, Abakaliki Received: 28 September 2021 Revised: 23 October 2021 Accepted: 29 October 2021 *Correspondence: Dr. Ayodele A. Olaleye, Email: ayodele_olaleye@yahoo.com Copyright: © the author(s), publisher and licensee Medip Academy. This is an open-access article distributed under the terms of the Creative Commons Attribution Non-Commercial License, which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. ABSTRACT Heterotopic pregnancy, coexistence of living or dead intrauterine pregnancy, single or multiple, with extra-uterine pregnancy located in the oviduct, ovary, uterine cornua, cervix or rarely peritoneal cavity. Heterotropic pregnancy is relatively uncommon in spontaneous conception with 1 in 30,000 cases reported, the incidence of heterotopic pregnancy increases to 1 in 3900 when conception is enhanced with various assisted reproduction techniques (ART). It is an ectopic pregnancy coexisting with intrauterine pregnancy. But is the incidence of heterotropic pregnancy rising? A case was reported from our centre in 2018 by Ejikeme et al, and we have recorded another two cases in the period of one year. Ectopic pregnancy has been described as a great masquerader, which makes diagnosis and management of heterotropic pregnancy a dilemma to attending physician. We present a case of an unbooked 26 years old G4P3+0 who has no family history of multiple gestation and presented at gestational age of 8 weeks and 5 days with 2 days history of abdominal pain and vaginal bleeding and 2 hours history of loss of consciousness. She later had exploratory laparotomy with left salpingectomy and manual vacuum aspiration of Retained Products of Conception with good outcome. In conclusion, spontaneous heterotropic pregnancy is a rare occurrence, however with advent of artificial reproductive technology and increase incidence of pelvic inflammatory disease, the incidence could be higher than earlier suspected. Keywords: Intra-uterine, Extra-uterine, Ectopic, Pregnancy, Heterotropic, Pelvic inflammatory disease