摘要

STUDY QUESTION: After an initial midtrimester loss, is the interval to the next conception associated with the risk of a recurrent loss? SUMMARY ANSWER: Among women who had a pregnancy loss at 14-19 weeks gestation, conception at least 3 months after this initial loss was associated with a reduced risk of a recurrent loss. WHAT IS KNOWN ALREADY: A short interpregnancy interval (IPI) has been thought to increase risk but recent studies of pregnancy after a loss have found no effect; however, these studies have been based almost entirely on an initial first trimester (<14 weeks) loss. STUDY DESIGN, SIZE, DURATION: A retrospective cohort study drawing on over 997 000 linked birth and hospital records from New South Wales, Australia for 2003-2011. Index pregnancies were those of women who had a first recorded pregnancy loss of 14-23 weeks gestation (miscarriage, termination and perinatal death). The study population was 4290 women who conceived again within 2 years. PARTICIPANTS/MATERIALS, SETTING, METHODS: The index loss was categorized by subgroups: 14-19 weeks gestation versus 20-23 weeks, and by whether spontaneous or a termination. The primary outcome was any loss or perinatal death before 24 weeks in the subsequent pregnancy. MAIN RESULTS AND THE ROLE OF CHANCE: After a 14-19 weeks index loss, an IPI of <= 3 months had an increased rate of recurrent loss compared with an IPI of >9-12 months: 21.9% versus 11.3% (adjusted relative risk (aRR) = 2.02, 95% CI 1.44-2.83). For women who had a spontaneous index loss of 20-23 weeks, there was no evidence that a short IPI increased or decreased the risk of recurrent loss. For any gestational age group of index losses, an IPI of >18-24 months increased the risk of a recurrent loss; the risk was highest after a 2023 weeks index loss (aRR = 2.15, 95% CI 1.18-3.91). LIMITATIONS, REASONS FOR CAUTION: We do not know how many cycles were required to achieve conception. Pregnancies resulting in early first trimester losses are unlikely to have resulted in hospitalization so would not have been identified. WIDER IMPLICATIONS OF THE FINDINGS: The risk of recurrent loss after an initial midtrimester loss may differ from the risk after an initial first trimester loss.

  • 出版日期2016-12