Women with twin pregnancy are at high risk for spontaneous preterm delivery. STOPPIT, funded by the CSO, recruited 500 women with twin pregnancy from nine UK National Health Service clinics specialising in the management of twin pregnancy. Women were randomised to either daily vaginal progesterone gel 90 mg (n=250) or to placebo gel (n=250) for 10 weeks from 24 weeks’ gestation. The primary outcome was delivery or intrauterine death before 34 weeks and 0 days of gestation.

The findings, published in The Lancet, demonstrated no evidence of progesterone reducing the composite outcome of risk of delivery or intrauterine death before 34 weeks of pregnancy in women with twin pregnancy. The study concluded that the clinical implication of the trial is that progestogens are not effective in women with twin pregnancy for prevention of preterm delivery.





Norman Jane E, Mackenzie Fiona,Owen Philip, Mactier Helen, Hanretty Kevin, Cooper Sarah, Calder Andrew, Mires Gary, Danielian Peter, Sturgiss Stephen, MacLennan Graeme, Tydeman Graham, Thornton Steven, Martin Bill, Thornton James G, Neilson James P, Norrie John.  Progesterone for the prevention of preterm birth in twin pregnancy (STOPPIT): a randomised, double-blind, placebo-controlled study and meta-analysis. Lancet 2009; 373: 2034–40