Heterotopic pregnancy complicating in vitro fertilization

A review was undertaken of the cases of heterotopic pregnancy resulting from in vitro fertilization/embryo transfer (IVF/ET) and frozen embryo replacement (FER) in a 6-year cohort of women at National Women's Hospital in Auckland. The incidence of heterotopic pregnancy was 2.9% (5 cases) in 173 clinical pregnancies resulting from 901 embryo replacements. Of the 5 women with heterotopic pregnancy, 1 had unilateral tubal patency and 4 had bilateral tubal blockage; 3 had 'high responder' peak serum oestradiol levels (greater than 9,000 pmol/L) prior to oocyte pick-up (OPU); 3 had a serum human chorionic gonadotrophin beta subunit (beta-HCG) level greater than 600 IU/L on Day 14 following embryo transfer (ET) in the absence of a multiple intrauterine gestation on subsequent ultrasound scan. In the 4 women in whom unequivocal diagnosis of heterotopic pregnancy was not made on the initial ultrasound scan, there was delay in appropriate management, in 1 for more than 5 months. In conclusion, early IVF pregnancies require a transvaginal ultrasound scan performed by a sonographer experienced in the diagnosis of ectopic pregnancy and management of early pregnancy complications by clinicians in close consultation with the IVF centre itself. No single risk factor, laboratory test or combination of these is sensitive or specific enough to predict the occurrence of heterotopic pregnancy. The first-line surgical treatment of heterotopic pregnancy should be laparoscopic salpingectomy with excision of all except the intramural portion of the affected Fallopian tube.