Primary abdominal pregnancy following intra-uterine insemination

Abstract

Primary abdominal pregnancy is an extremely rare type of extrauterine pregnancy. It has been reported from many unusual intra-abdominal sites. We report a case of primary abdominal pregnancy following intra-uterine insemination (not reported earlier to our knowledge). Implanted on the anterior surface of the uterus possibly related to an endometriotic foci. Early diagnosis enabled laparoscopic management of this case.

INTRODUCTION

Primary abdominal pregnancy is possibly the rarest form of extrauterine gestation. Incidence is not known. Abdominal pregnancies (both primary and secondary) have a reported incidence of 1 in 10,000.[1] Worldwide, the incidence of ectopic pregnancies is increasing, with significant contribution from assisted reproductive technologies (ART).[2] However, the incidence of abdominal pregnancies have remained constant or reduced, and maternal mortality reduced from 20% to less than 5% in last 20 years[3] due to early diagnosis and management. Early diagnosis has enabled laparoscopic management in many of these cases. In this study, we report a case of primary abdominal pregnancy following intra-uterine insemination (IUI) managed laparoscopically.

CASE REPORT

Mrs. Y.P, a 31-year-old female, attended our OPD on 22^nd August 2010, with chief complaints of amenorrhea of 2 months, following an IUI cycle. She had primary infertility of 3 years, and was undergoing IUI for mild-to-moderate male factor coupled with mild pelvic endometriosis. This was her first IUI cycle (CC1 00 mg D2-D6, HCG trigger, and dydrogestrone as luteal support). Urine pregnancy test was negative on two ocasions after IUI. She had no other complaints [Figures 1–6].

Figure 1.

The undisturbed ectopic gestation sac seen on the anterior surface of the uterus and anterior leaf of broad ligament

Figure 6.

Implantation site after removal of ectopic sac and hemostasis

Her previous menstrual cycles were regular. LMP was performed 28.06.2010. Double IUI was done on 12^th and 13^th July 2010. She was amenorrhoeic for almost 9 weeks. On transvaginal sonography, the uterus was bulky, very thick regular echogenic endometrium, and no gestational sac in cavity [Figure 7]. Both ovaries were normal with a corpus luteum in the left ovary [Figures 8 and 9]. There was a 1.6 cm mass with strongly echogenic rim, close to the uterus, in the left side suggestive of an ectopic pregnancy sac. Serum b-HCG in the same day was 9470 mIU/ml [Figures 10 and 11].

Figure 7.

Uterus with empty endometrial cavity

Figure 8.

Transvaginal scan showing left ovary with a corpus luteum

Figure 9.

Image of the normal right ovary

Figure 10.

Transvaginal sonography showing ectopic gestational sac in the region of the left adnexa

Figure 11.

Transvaginal sonography picture showing both the empty uterus and adjacent ectopic sac

Laparoscopy was offered to the patient, who however, desperately requested for the conservative approach (she had undergone diagnostic hystero-laparoscopy 2 months back during her infertility workup , and also did not want to loose a fallopian tube).

She was given one intramascular injection of methotrexate (50 mg) on 22.08.2010 following routine blood tests. However, follow-up of serial b-HCG on 26.08.2010 showed persisting levels of 9300 mIU/ml and transvaginal sonography showed a size of the mass increased to 2 cm.

She was taken up for laparoscopic surgery on 28.08.2010. At laparoscopy uterus was bulky, deviated to the right side with a few old and new endometriotic deposits on the antero-superior surface. Both the fallopian tubes and ovaries were normal. Pouch of Douglas was free. No fresh or old blood was found in the peritoneal cavity. The pregnancy sac was implanted on the peritoneal surface of the broad ligament,between the round ligament and the utero-vesical fold.

Initial appearance was a mound-like elevation, with yellowish brown margins [Figures 1 and 2]. Fresh bleeding started only upon manipulation of the uterus. Gestational sac was sucked out [Figures 3 and 4]. There was significant bleeding from the base [Figure 5], which was controlled with bipolar coagulation and superficial infiltration of Pitressin [Figure 6]. Endometrial curettage was performed. The product of conception retrieved was sent for histopathology [Figure 12]. The patient made an uneventful postoperative recovery. β-HCG fell to 203 IU within 4 days, and subsequently declined to non-pregnant levels.

Figure 2.

The ectopic pregnancy site which started to bleed,on manipulation of the uterus

Figure 3.

Bleeding ectopic sac separating from peritoneal surface

Figure 4.

Protruding gestational sac

Figure 5.

Bleeding from the implantation site after gestational sac was sucked out

Figure 12.

Histopathology picture showing chorionic villi, bleeding, and no tubal epithelium. (a and b) Low and high magnification

DISCUSSION

Most gynecologists would not encounter a case of abdominal pregnancy during their career. Incidence has been reported as approximately 1 in 10,000 live births,[1] and 9.2 per 1000 ectopic pregnancies.[4] Most of these are secondary abdominal pregnancies, which means the embryo had primarily implanted in the fallopian tube, extruded, or expelled and then secondarily implanted itself on another intra-abdominal surface.[4]

In primary abdominal pregnancy, which is the rarest type of ectopic gestation, the conceptus implants on the peritoneal surface.

Studdiford's criteria used to diagnose primary abdominal pregnancy are described as:

1. The presence of normal bilateral tubes and ovaries with no evidence of recent or past pregnancy.

2. No evidence of a uteroperitoneal fistula.

3. The presence of pregnancy related exclusively to the peritoneal surface, early enough to eliminate the possibility of secondary implantation after primary tubal nidation.[5]

Alternatively, a classification relevant from diagnosis and treatment defines early peritoneal pregnancy (≥20 weeks of gestation) or advanced (≤20 weeks of gestation).[6]

Primary abdominal pregnancies have been reported from omentum, sigmoid colon, posterior peritoneum of pelvis, spleen, liver, diaphragm, obturator foramen, posterior surface of uterus, retroperitoneum, and pancreas.[7–21]

Primary peritoneal pregnancy has been reported in relation to foci of endometriosis.[21,22]

ART has contributed significantly to the increased incidence of ectopic pregnancies. Rare and new varieties of ectopics such as heterotopic pregnancies, cervical, cesarean scar pregnancies have surfaced. However, the incidence of abdominal pregnancies has not changed, may be reduced due to early diagnosis.[23,24] Presentation of patents with primary abdominal pregnancy varies greatly,[6] however, with early diagnosis like our case, patients may be totally asymptomatic.

In earlier literature abdominal pregnancies were typically diagnosed late. Now with serial b-HCG, excellent ultrasonography, and MRI facilities, these pregnancies are diagnosed much earlier.[25,26]

Our case is unique in some aspects. To our knowledge, this is the only case reported of primary peritoneal pregnancy in the anterior peritoneal leaf of the broad ligament following intrauterine insemination.

The implantation appears to be related to endometriotic foci. The presence of uterine surface endometriosis was documented by a routine diagnosis laparoscopy only 2 months earlier.

CONCLUSIONS

With early diagnosis laparoscopic management becomes feasible. Prognosis for future fertility also appears good following early diagnosis, as the tubes, ovaries are not directly involved in pregnancy, nor removed during the operative procedure and are not involved in postoperative adhesion formation. Future fertility does not appear to be adversely affected.[6]