Tissue & Cell｜孕期时常做运动，胎盘血供更充足
怀孕能不能运动？需不需要运动？这是很多孕妈都很关心的话题。有证据表明，孕妈在孕期是可以运动的，并且适量适当的运动还会有益孕妈和胎儿的健康。
但是，其中有个很少有研究涉及的关键部位——胎盘，爱思唯尔旗下全医学信息平台ClinicalKey中，期刊Tissue and Cell上发表了一篇综述[1]，让我们得以了解运动对胎盘造成的直接影响。
胎盘的结构与作用
母胎界面器官之间的交流对于成功怀孕至关重要。胎盘分为两侧：胎盘的胎儿部分是绒毛膜，而母体部分是基底蜕膜。母胎界面具有抵御局部病原体感染的能力[2,3]。它介导了氧气、二氧化碳和营养物质的转移[4]，发挥免疫保护作用，并产生各种激素、酶和细胞因子，在建立和维持成功怀孕方面发挥着至关重要的作用[5]。
运动对母胎整体
健康的益处
产前锻炼已被证明可以降低剖腹产率，降低妊娠并发症的发生率[8-12]。此外，产前锻炼被发现可以减少产后体重滞留，减轻背部和骨盆疼痛，减少疲劳、压力和分娩并发症，预防和控制尿失禁[13,14]。图2总结了母体和胎儿的益处。
运动如何影响胎盘？
让胎盘血供更佳
胎盘血液循环是哺乳动物的一个独特特征。胎盘内有母体和胎儿两套血循环。胎儿的静脉血经脐动脉及其分支流入绒毛毛细血管，与绒毛间隙内的母体血进行物质交换后，成为动脉血，又经脐静脉回流到胎儿。母体动脉血从子宫螺旋动脉流入绒毛间隙，在此与绒毛内毛细血管的胎儿血进行物质交换后，由子宫静脉回流入母体。
有研究证实怀孕期间运动可以提高胎盘效率以及子宫胎盘灌注[15,16]，增加胎盘的生长[17,18]，增加胎盘的血管容量和毛细血管表面积，提高胎盘血流量[22-24]，并增加血管生成因子 VEGF 及其受体 VEGFR1 [25]。
短暂缺氧再恢复
胎盘经历练才能成长
在一项对妊娠最后三个月的孕妇进行5分钟短时间运动的研究中，多普勒超声检查发现运动会增加子宫胎盘血管阻力[26]。这表明子宫胎盘血流量短暂减少。子宫胎盘血流量的短暂减少可能会造成短暂的缺氧环境，在运动后立即促进子宫胎盘血流量，从而导致绒毛间隙突然再充氧。因此，绒毛在产前运动期间会在胎盘绒毛间隙中经历间歇性缺氧/复氧的情况。
在妊娠11周前正常胎盘发育期间，胎盘PO2（Partial Pressure of Oxygen，PO2）比蜕膜PO2低 2.5 倍[27]。在妊娠 10-12 周之间，随着母胎循环的建立，流入绒毛间隙的母体血流量导致绒毛间隙中PO2的增加。PO2的这些变化有助于胎盘的正常发育。运动导致绒毛间隙缺氧/复氧情况就类似于怀孕第 10-12 周正常胎盘发育中发生的情况。通过调节缺氧诱导因子1ɑ （HIF-1）来支持胎盘血管发育并增强细胞抗氧化防御能力[28]。因此，运动诱发的绒毛间隙中PO2的潜在变化可能会影响胎盘血管生成，并最终影响母体-胎盘-胎儿循环（图3）。
运动还能影响
胎盘激素水平
胎盘作为母胎之间的关键界面，促进氧气和气体的交换，负责合成各种对妊娠发育和维持必不可少的激素（图 5）。这个临时器官的内分泌功能在整个怀孕期间至关重要。
胎盘雌激素由雌酮（E1）、17β-雌二醇（E2）、雌三醇（E3）和雌甾醇（E4）组成。一项研究报告表明，在前 10 分钟运动期间，妊娠晚期孕妇的循环 E3 显著增加，运动后一小时后下降至略低于基线水平[29]。另一组报告在中等强度的自行车运动 30 分钟后，孕妇体内 E3 的循环水平显著增加[30]。目前尚不清楚运动是否会改变胎盘雌激素的产生或分泌，但运动可能会增加流向子宫胎盘循环的富含雌激素的血流量。
结语
胎盘是成功妊娠结果的核心，并在许多妊娠疾病或并发症的发病机制中发挥重要作用。怀孕期间的体育运动可能通过血管生成途径、血流供氧、胎盘雌激素分泌等影响胎盘生物学，从而对母亲和后代产生各种益处。
参考文献
[1].Jayonta Bhattacharjee, Shuhiba Mohammad, Kristi B. Adamo.: Does exercise during pregnancy impact organs or structures of the maternal-fetal interface? Tissue and Cell. 2021; 72
[2]. Le Bouteiller P., and Bensussan A.: Up-and-down immunity of pregnancy in humans. F1000Res 2017; 6: pp. 1216
[3]. Schumacher A., Sharkey D.J., Robertson S.A., and Zenclussen A.C.: Immune cells at the fetomaternal interface: how the microenvironment modulates immune cells to foster fetal development. J. Immunol. 2018; 201: pp. 325-334
[4]. Faas M.M., and de Vos P.: Uterine NK cells and macrophages in pregnancy. Placenta 2017; 56: pp. 44-52
[5]. Hsu P., Santner-Nanan B., Dahlstrom J.E., Fadia M., Chandra A., Peek M., and Nanan R.: Altered decidual DC-SIGN+ antigen-presenting cells and impaired regulatory T-cell induction in preeclampsia. Am. J. Pathol. 2012; 181: pp. 2149-2160
[6]. Medicine A.Co.S.: ACSM’s Guidelines for Exercise Testing and Prescription. Lippincott Williams & Wilkins, 2013.
[7]. Warburton D.E., Nicol C.W., and Bredin S.S.: Health benefits of physical activity: the evidence. Cmaj 2006; 174: pp. 801-809
[8]. Cid M., and González M.: Potential benefits of physical activity during pregnancy for the reduction of gestational diabetes prevalence and oxidative stress. Early Hum. Dev. 2016; 94: pp. 57-62
[9]. Davenport M.H., McCurdy A.P., Mottola M.F., Skow R.J., Meah V.L., Poitras V.J., Jaramillo Garcia A., Gray C.E., Barrowman N., Riske L., Sobierajski F., James M., Nagpal T., Marchand A.A., Nuspl M., Slater L.G., Barakat R., Adamo K.B., Davies G.A., and Ruchat S.M.: Impact of prenatal exercise on both prenatal and postnatal anxiety and depressive symptoms: a systematic review and meta-analysis. Br. J. Sports Med. 2018; 52: pp. 1376-138
[10]. Davenport M.H., Ruchat S.M., Sobierajski F., Poitras V.J., Gray C.E., Yoo C., Skow R.J., Jaramillo Garcia A., Barrowman N., Meah V.L., Nagpal T.S., Riske L., James M., Nuspl M., Weeks A., Marchand A.A., Slater L.G., Adamo K.B., Davies G.A., Barakat R., and Mottola M.F.: Impact of prenatal exercise on maternal harms, labour and delivery outcomes: a systematic review and meta-analysis. Br. J. Sports Med. 2019; 53: pp. 99-107
[11]. Di Mascio D., Magro-Malosso E.R., Saccone G., Marhefka G.D., and Berghella V.: Exercise during pregnancy in normal-weight women and risk of preterm birth: a systematic review and meta-analysis of randomized controlled trials. Am. J. Obstet. Gynecol. 2016; 215: pp. 561-571
[12]. Ruchat S.M., Mottola M.F., Skow R.J., Nagpal T.S., Meah V.L., James M., Riske L., Sobierajski F., Kathol A.J., Marchand A.A., Nuspl M., Weeks A., Gray C.E., Poitras V.J., Jaramillo Garcia A., Barrowman N., Slater L.G., Adamo K.B., Davies G.A., Barakat R., and Davenport M.H.: Effectiveness of exercise interventions in the prevention of excessive gestational weight gain and postpartum weight retention: a systematic review and meta-analysis. Br. J. Sports Med. 2018; 52: pp. 1347-1356
[13]. Harrison C.L., Brown W.J., Hayman M., Moran L.J., and Redman L.M.: The role of physical activity in preconception, pregnancy and postpartum health. Semin. Reprod. Med. 2016; 34: pp. e28-37
[14]. Nascimento S.L., Surita F.G., and Cecatti J.G.: Physical exercise during pregnancy: a systematic review. Curr. Opin. Obstet. Gynecol. 2012; 24: pp. 387-394
[15]. Ramirez-Velez R., Bustamante J., Czerniczyniec A., Aguilar de Plata A.C., and Lores-Arnaiz S.: Effect of exercise training on eNOS expression, NO production and oxygen metabolism in human placenta. PLoS One 2013; 8:
[16]. Reyes L.M., and Davenport M.H.: Exercise as a therapeutic intervention to optimize fetal weight. Pharmacol. Res. 2018; 132: pp. 160-167
[17]. ClApp J.F., and Rizk K.H.: Effect of recreational exercise on midtrimester placental growth. Am. J. Obstet. Gynecol. 1992; 167: pp. 1518-1521
[18]. Jackson M.R., Gott P., Lye S.J., Ritchie J.W., and ClApp J.F.: The effects of maternal aerobic exercise on human placental development: placental volumetric composition and surface areas. Placenta 1995; 16: pp. 179-191
[19]. Hilde G., Eskild A., Owe K.M., Bo K., and Bjelland E.K.: Exercise in pregnancy: an association with placental weight? Am. J. Obstet. Gynecol. 2017; 216: pp. 168.e161-168.e169
[20]. Juhl M., Olsen J., Andersen P.K., Nohr E.A., and Andersen A.M.: Physical exercise during pregnancy and fetal growth measures: a study within the Danish National Birth Cohort. Am. J. Obstet. Gynecol. 2010; 202: pp. e61-68
[21]. Everest C., Nagpal T.S., Souza S.C.S., da Silva D.F., Gaudet L., Mohammad S., Bhattacharjee J., and Adamo K.B.: The effect of maternal physical activity and gestational weight gain on placental efficiency. Med. Sci. Sports Exerc. 2021; 53: pp. 756-762
[22]. ClApp J.F., Kim H., Burciu B., Schmidt S., Petry K., and Lopez B.: Continuing regular exercise during pregnancy: effect of exercise volume on fetoplacental growth. Am. J. Obstet. Gynecol. 2002; 186: pp. 142-147
[23]. Jackson M.R., Gott P., Lye S.J., Ritchie J.W., and ClApp J.F.: The effects of maternal aerobic exercise on human placental development: placental volumetric composition and surface areas. Placenta 1995; 16: pp. 179-191
[24]. Krause Neto W., and Gama E.F.: Exercise effect on placental components: systematic review and meta-analysis. Rev. Bras. Med. Do Esporte 2015; 21: pp. 485-489
[25]. Bhattacharjee J., Mohammad S., Goudreau A.D., and Adamo K.B.: Physical activity differentially regulates VEGF, PlGF, and their receptors in the human placenta. Physiol. Rep. 2021; undefined: pp. 9
[26]. Morrow R.J., Ritchie J.W., and Bull S.B.: Fetal and maternal hemodynamic responses to exercise in pregnancy assessed by Doppler ultrasonography. Am. J. Obstet. Gynecol. 1989; 160: pp. 138-140
[27]. Jauniaux E., Watson A., and Burton G.: Evaluation of respiratory gases and acid-base gradients in human fetal fluids and uteroplacental tissue between 7 and 16 weeks’ gestation. Am. J. Obstet. Gynecol. 2001; 184: pp. 998-1003
[28]. Carter A.M.: Placental oxygen consumption. Part I: in vivo studies--a review. Placenta 2000; 21: pp. S31-37
[29]. Rauramo I., Andersson B., Laatikainen T., and Pettersson J.: Stress hormones and placental steroids in physical exercise during pregnancy. Br. J. Obstet. Gynaecol. 1982; 89: pp. 921-925
[30]. Bonen A., Campagna P., Gilchrist L., Young D.C., and Beresford P.: Substrate and endocrine responses during exercise at selected stages of pregnancy. J. Appl. Physiol. 1992; 73: pp. 134-142
