LAUSR

Abstract Background Women with a history of recurrent miscarriage are accorded dedicated medical care during a subsequent pregnancy (or subsequent pregnancies). Previous studies of subsequent pregnancy and perinatal outcome in women with a history of recurrent miscarriage give conflicting results, with some reporting an increase in adverse obstetric and perinatal outcomes, and others reporting no difference. There is a lack of systematic review based on a large-scale population. Methods We carried out a systematic review and meta-analysis to incorporate direct and indirect data from relevant studies. We searched PubMed, Scopus, Embase, Web of Science, and Ovid, up to Dec 31, 2017. Studies that were included were full text reports of pregnancy outcomes in women with a history of recurrent miscarriage. We used the random-effect model or the fixed-effect model to estimate the incidence of different obstetric and perinatal outcomes. We also carried out subgroup analysis to determine the effect of the sex of the fetus on the incidence of different obstetric and perinatal outcomes. Findings Among 1842 full articles retrieved, 7 articles with a total of 224 879 participants, including 10 174 women with a history of recurrent miscarriage and 21 4705 control subjects, were included in this systematic review and meta-analysis. Recurrent miscarriage was associated with a significantly increased incidence of antepartum haemorrhage (odds ratio [OR] 2·38, 95% CI 1·98–5·27), gestational diabetes (1·23, 1·02–1·47), preterm delivery (1·73, 1·28–2·07), small for gestational age (1·52, 1·19–1·98), and perinatal death (2·30, 1·62–4·97). There was no significant difference in the incidence of gestational hypertension, or in Apgar scores at 1 and 5 minutes after birth. There was also no significant difference in risk between male fetus and female fetus. Interpretation Women with a history of recurrent miscarriage have an increased risk of several obstetric and perinatal complications, and therefore may require more dedicated medical care in their subsequent pregnancies. Funding This work was supported by the Health and Medical Research Fund in Hong Kong (number 04152786) and the Hong Kong Obstetrical and Gynaecological Trust Fund in 2017.