MRC Centre for Reproductive Health, The University of Edinburgh, Queen's Medical Research Institute, Edinburgh, UK.
Reprod Fertil. 2022 Apr 7;3(2):C4-C6. doi: 10.1530/RAF-21-0122. eCollection 2022 Apr 1.
In November 2021, NICE updated its clinical guideline that covers the management of threatened miscarriage in the first trimester. They recommended offering vaginal micronised progesterone twice daily until 16 completed weeks of pregnancy in those with a previous miscarriage. However, the duration of treatment is not evidence based. In the major clinical trial that informed the guideline, there was no benefit in starting progesterone after 9 weeks and the full effect of progesterone was present at 12 weeks of pregnancy. There are theoretical risks impacting offspring health in later life after maternal pharmaceutical progesterone treatment. As the effect of progesterone seems to be complete by 12 weeks of gestation, we should consider carefully whether to follow the guidance and treat up to 16 weeks of pregnancy.
In November 2021, new guidelines were published about the management of bleeding in early pregnancy. If someone who has had a previous miscarriage starts bleeding, they should now be treated with progesterone as this slightly reduces the chance of miscarriage. The guideline says progesterone should be given if the pregnancy is in the womb, and potentially normal, until 16 weeks of pregnancy. However, in the big studies looking at progesterone's effect in reducing miscarriage the beneficial effects of progesterone were complete by 12 weeks of pregnancy. At that stage, it is the placenta and not the mother's ovary that makes the progesterone to support the pregnancy. We do not know the long-term effects of giving extra progesterone during pregnancy on the offspring. Some research has raised the possibility that there might be some adverse effects if progesterone is given for too long. Maybe the guidance should have suggested stopping at 12 weeks rather than 16 weeks of pregnancy.
2021 年 11 月，NICE 更新了涵盖孕早期难免流产管理的临床指南。他们建议对于有过流产史的患者，每日两次阴道给予微粒化黄体酮，直至妊娠 16 周。但是，治疗持续时间没有证据支持。在为指南提供信息的主要临床试验中，在 9 周后开始使用黄体酮没有获益，而在妊娠 12 周时黄体酮的全部作用才显现出来。母体药物黄体酮治疗后，对子代健康存在潜在的远期风险。由于黄体酮的作用似乎在妊娠 12 周时完全显现，我们应该仔细考虑是否要遵循这一指导意见，将治疗时间延长至 16 周。
2021 年 11 月，发表了关于早期妊娠出血管理的新指南。如果有过流产史的患者开始出血，现在应使用孕激素治疗，因为这可略微降低流产的几率。该指南指出，如果妊娠在子宫内且可能正常，应给予孕激素治疗直至妊娠 16 周。然而，在研究孕激素减少流产作用的大型研究中，孕激素的有益作用在妊娠 12 周时就已完全显现。此时，支持妊娠的是胎盘而不是母亲的卵巢产生孕激素。我们不知道在妊娠期间给予额外孕激素对后代的长期影响。一些研究提出，如果孕激素使用时间过长，可能会有一些不良影响。也许指南应该建议在妊娠 12 周而不是 16 周时停止治疗。
