Risk factors for higher order multiples following stimulated intrauterine insemination

Keywords:

intrauterine insemination, higher order multiples, prevention

A. J. BENSDORP, F. VAN DER VEEN, B. W. MOL, M. VANWELY

Center for Reproductive Medicine, Department of Obstetrics and Gynaecology, Academic Medical Centre, Amsterdam,
1106 AD Amsterdam.

Correspondence at: a.j.bensdorp@amc.uva.nl

Abstract

Higher Order Multiple Pregnancies (HOMP) are defined as pregnancies with three or more foetuses. Higher Order Multiple Births (HOMB) are defined as deliveries of three or more babies.
Over the last decades, there has been a four to eight fold increase of higher order multiple births. This increase can mainly be attributed to fertility treatments, but the exact attribution for stimulated intrauterine insemination (IUI COH) is not known, since IUI treatments are not always recorded. It is generally accepted that multiple gestations are high risk pregnancies. They are associated with maternal, obstetric, and perinatal complications, and neonatal and infant mortality In addition, they are associated with increased financial and negative psychological consequences. These risks and consequences are higher for HOMPS than for twins.
This overview summarizes briefly how to prevent higher order multiple pregnancies in IUI COH. In order to prevent HOMP, prediction models can be used to distinguish patients with a good prognosis for a spontaneous pregnancy. In this patient group expectant management needs to be considered. With mild stimulation protocols, and monitoring, particularly in young women and especially in their first cycles, most high order multiples can easily be prevented.
Pregnancy rates can be increased by immobilisation following IUI, without a further increasing risk of HOMP. When primary prevention fails, cancelling of cycles is a low impact option for secondary prevention. Remedies such as aspiration of supernumerary follicles, or converting to IVF or should be considered as a last resort. This applies especially for Multifoetal Pregnancy Reduction (MFPR).