The natural history of multiple pregnancies after assisted reproduction: is spontaneous fetal demise a clinically significant phenomenon?
OBJECTIVE
To determine the rate of spontaneous fetal demise after heartbeats are demonstrated in multiple pregnancies conceived after IVF-ET.


METHODS
Retrospective case series.


METHODS
University-based IVF-ET program.


METHODS
Eighty-one patients in whom initial transvaginal ultrasound (US) study, performed at 5 to 6 weeks of gestation, identified more than one gestational sac. Total number of sacs was 191.


METHODS
Patients were followed by serial US examinations.


METHODS
Outcome of pregnancies.


RESULTS
Twenty-four empty gestational sacs were identified in 21 patients, of whom 15 delivered, 2 miscarried, and 4 are currently ongoing beyond first trimester. Of the 167 initially viable embryos, 9 (5%) underwent spontaneous fetal demise. In 5 of these 9 pregnancies, initial US identified significant interfetal size variation.


CONCLUSIONS
The rate of spontaneous fetal demise for a specific embryo in multiple gestation, after fetal heartbeats have been identified in early pregnancy, is 5%. This rate is similar to that seen in spontaneous conceptions. The chance of future fetal demise increases if first trimester interfetal size variation is significant.
Kol
S
S
Department of Obstetrics and Gynecology, Rambam Medical Center, Haifa, Israel.
Levron
J
J
Lewit
N
N
Drugan
A
A
Itskovitz-Eldor
J
J
D000022:Abortion, Spontaneous / Q000000981:diagnostic imaging / Q000453:epidemiology*; D000328:Adult; D004624:Embryo Transfer; D005260:Female; D005307:Fertilization in Vitro; D005323:Fetal Monitoring; D006801:Humans; D011247:Pregnancy; D011272:Pregnancy, Multiple; D014463:Ultrasonography