{
  "abstract": "Background The optimal interpregnancy intervals (IPI) following miscarriage remain unclear in women undergoing frozen embryo transfer (FET).Materials and methods The retrospective study enrolled 2905 participants who underwent FET after miscarriage at the Center for Reproductive Medicine, Department of Obstetrics and Gynecology, Peking University Third Hospital between January 2015 and December 2022. The participants were categorised into four groups based on their IPI: 0–3 months (n=165), 4–6 months (n=1169), 7–12 months (n=1083) and >12 months (n=488). Logistic regression and restricted cubic splines were applied to assess the association between IPI and fertility and neonatal outcomes. Live birth rate was the primary outcome.Results A decreasing trend of OR of live birth was observed as IPI increased. Compared with IPI between 4 and 6 months, the live birth rate decreased significantly in IPI >1 year (adjusted OR (aOR) 0.71, 95% CI 0.56 to 0.91); the rate of preterm delivery decreased significantly in IPI >1 year (aOR 0.38, 95% CI 0.15 to 0.96). No significant differences were observed in other fertility outcomes including clinical pregnancy, multiple pregnancy, miscarriage and biochemical pregnancy, and neonatal outcomes including caesarean section, infant sex, low birth weight, macrosomia, large for gestational week and short for gestational week.Conclusion Women who underwent FET after a miscarriage within 1 year may be associated with higher live birth rates. This study provides no evidence to support the routine delay of FET.",
  "authors": [
    {
      "affiliations": [
        "State Key Laboratory of Female Fertility Promotion, Center for Reproductive Medicine, Department of Obstetrics and Gynecology, Peking University Third Hospital, Beijing, China",
        "National Clinical Research Center for Obstetrics and Gynecology (Peking University Third Hospital), Beijing, China",
        "Key Laboratory of Assisted Reproduction (Peking University), Ministry of Education, Beijing, China",
        "Beijing Key Laboratory of Collaborative Innovation in Frontier Technologies for Population Quality, Beijing, China",
        "National Clinical Key Specialty Construction Program, P. R. China (2023), Beijing, China"
      ],
      "name": "Di Mao"
    },
    {
      "affiliations": [
        "State Key Laboratory of Female Fertility Promotion, Center for Reproductive Medicine, Department of Obstetrics and Gynecology, Peking University Third Hospital, Beijing, China",
        "National Clinical Research Center for Obstetrics and Gynecology (Peking University Third Hospital), Beijing, China",
        "Key Laboratory of Assisted Reproduction (Peking University), Ministry of Education, Beijing, China",
        "Beijing Key Laboratory of Collaborative Innovation in Frontier Technologies for Population Quality, Beijing, China",
        "National Clinical Key Specialty Construction Program, P. R. China (2023), Beijing, China"
      ],
      "name": "Kai-Lun Hu"
    },
    {
      "affiliations": [
        "State Key Laboratory of Female Fertility Promotion, Center for Reproductive Medicine, Department of Obstetrics and Gynecology, Peking University Third Hospital, Beijing, China",
        "National Clinical Research Center for Obstetrics and Gynecology (Peking University Third Hospital), Beijing, China",
        "Key Laboratory of Assisted Reproduction (Peking University), Ministry of Education, Beijing, China",
        "Beijing Key Laboratory of Collaborative Innovation in Frontier Technologies for Population Quality, Beijing, China",
        "National Clinical Key Specialty Construction Program, P. R. China (2023), Beijing, China"
      ],
      "name": "Mingmei Lin"
    },
    {
      "affiliations": [
        "State Key Laboratory of Female Fertility Promotion, Center for Reproductive Medicine, Department of Obstetrics and Gynecology, Peking University Third Hospital, Beijing, China",
        "National Clinical Research Center for Obstetrics and Gynecology (Peking University Third Hospital), Beijing, China",
        "Key Laboratory of Assisted Reproduction (Peking University), Ministry of Education, Beijing, China",
        "Beijing Key Laboratory of Collaborative Innovation in Frontier Technologies for Population Quality, Beijing, China",
        "National Clinical Key Specialty Construction Program, P. R. China (2023), Beijing, China"
      ],
      "name": "Fen-Ting Liu"
    },
    {
      "affiliations": [
        "State Key Laboratory of Female Fertility Promotion, Center for Reproductive Medicine, Department of Obstetrics and Gynecology, Peking University Third Hospital, Beijing, China",
        "National Clinical Research Center for Obstetrics and Gynecology (Peking University Third Hospital), Beijing, China",
        "Key Laboratory of Assisted Reproduction (Peking University), Ministry of Education, Beijing, China",
        "Beijing Key Laboratory of Collaborative Innovation in Frontier Technologies for Population Quality, Beijing, China",
        "National Clinical Key Specialty Construction Program, P. R. China (2023), Beijing, China"
      ],
      "name": "Zhonghong Zeng"
    },
    {
      "affiliations": [
        "State Key Laboratory of Female Fertility Promotion, Center for Reproductive Medicine, Department of Obstetrics and Gynecology, Peking University Third Hospital, Beijing, China",
        "National Clinical Research Center for Obstetrics and Gynecology (Peking University Third Hospital), Beijing, China",
        "Key Laboratory of Assisted Reproduction (Peking University), Ministry of Education, Beijing, China",
        "Beijing Key Laboratory of Collaborative Innovation in Frontier Technologies for Population Quality, Beijing, China",
        "National Clinical Key Specialty Construction Program, P. R. China (2023), Beijing, China"
      ],
      "name": "Dan Mo"
    },
    {
      "affiliations": [
        "State Key Laboratory of Female Fertility Promotion, Center for Reproductive Medicine, Department of Obstetrics and Gynecology, Peking University Third Hospital, Beijing, China",
        "National Clinical Research Center for Obstetrics and Gynecology (Peking University Third Hospital), Beijing, China",
        "Key Laboratory of Assisted Reproduction (Peking University), Ministry of Education, Beijing, China",
        "Beijing Key Laboratory of Collaborative Innovation in Frontier Technologies for Population Quality, Beijing, China",
        "National Clinical Key Specialty Construction Program, P. R. China (2023), Beijing, China"
      ],
      "name": "Rong Li"
    }
  ],
  "title": "Association between interpregnancy interval following vacuum aspiration after miscarriage and fertility and neonatal outcomes",
  "uid": "9b3e3e4b-d52e-5649-b239-6c5badf1dcc2"
}