Women who lie on their backs for 15 minutes after artificial insemination have a ‘significantly higher’ chance of getting pregnant than those who move around straight after treatment.
Dutch researchers are now calling for all women undergoing intrauterine insemination to be offered 15 minutes of immobilisation after the procedure.
Writing in the BMJ (http://www.bmj.com/cgi/doi/10.1136/bmj.b4080), the authors, led by Dr Inge Custers from the Academic Medical Centre in Amsterdam, found that the ongoing pregnancy rate was significantly higher in the immobilisation group: 27 per cent (54) v 18 per cent (34).
Intrauterine insemination with or without ovarian hyperstimulation is one of the most common methods of fertility treatment provided globally. While some small-scale studies have investigated links between immobilisation and the success of intrauterine insemination, this is the first large-scale trial to do so.
“Although immobilisation takes more time and occupies more space in busy rooms, the intervention will be economic in the long run, as pregnant patients will not return in subsequent cycles,” commented Dr Custers.
The mechanism of the effect of immobilisation after insemination is unclear. The researchers explained that after coitus, spermatozoa enter the cervix through the cervical mucus into the uterus, leaving the seminal plasma behind in the vagina.
In intrauterine insemination, spermatozoa are inseminated in a small volume of fluid directly into the uterus. “As a consequence, immediate mobilisation might cause leakage of this volume together with spermatozoa out of the uterus; alternatively, movement of processed sperm to and up the fallopian tubes may take longer than after intercourse,” they suggested.
In an accompanying editorial, Prof William Ledger from the University of Sheffield said that while Custers’ research showed promise, further studies were needed.
He suggested that units should carry out their own evaluation to test the hypothesis in the ‘real world’ and that “if successful, more couples could be spared the rigorous and costly process of in vitro fertilisation.”