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نقش اختلالات سیستم ایمنی در شکست مکرر درمان ناباروری

نقش اختلالات سیستم ایمنی در شکست مکرر درمان ناباروری

عوامل مربوط به سیستم ایمنی از جمله عوامل اثرگذار در وقوع بارداری و حفظ آن است. سیستم ایمنی بدن به‌طور طبیعی نقش محافظ در برابر عوامل مهاجم را بازی می‌کند، اما در مواردی ممکن است از تعادل خارج شود و جنین را به‌عنوان جسم خارجی شناسایی کند و به آن حمله کند. در چنین مواردی

نقش اختلالات سیستم ایمنی در شکست مکرر درمان ناباروری

عوامل مربوط به سیستم ایمنی از جمله عوامل اثرگذار در وقوع بارداری و حفظ آن است. سیستم ایمنی بدن به‌طور طبیعی نقش محافظ در برابر عوامل مهاجم را بازی می‌کند، اما در مواردی ممکن است از تعادل خارج شود و جنین را به‌عنوان جسم خارجی شناسایی کند و به آن حمله کند. در چنین مواردی اختلالات سیستم ایمنی می‌تواند مانع لانه‌گزینی جنین و یا عامل سقط باشد.

به گزارش ایسنا، دکتر مریم توکلی _ متخصص ایمونولوژی و عضو تیم تخصصی مرکز درمان ناباروری ابن‌سینا درباره نقش سیستم ایمنی در وقوع و تداوم بارداری، گفت: نیمی از جنین متعلق به پدر است و بنابراین برای بدن مادر غریبه محسوب می‌شود و سیستم ایمنی بدن مادر به آن واکنش نشان می‌دهد. در یک بارداری موفق، سیستم ایمنی بدن مادر خود را با جنین تطبیق می‌دهد و آن را می‌پذیرد، اما اگر سیستم ایمنی بدن مادر به هر دلیلی تعادل خود را از دست دهد،  ممکن است دچار اختلال شود و نتواند خود را با جنین تطبیق دهد و در نتیجه، آن را پس بزند. این پس زدن ممکن است از همان ابتدا رخ دهد و مانع لانه‌گزینی جنین شود یا پس از وقوع بارداری رخ دهد و به سقط جنین بینجامد.

وی با اشاره به زمان سقط جنین ناشی از عوامل ایمونولوژیک، عنوان کرد: سقط‌های مربوط به سیستم ایمنی معمولاً در سه ماهه نخست بارداری‌ اتفاق می‌افتد. البته بعضی از اختلالات سیستم ایمنی ممکن است به بروز سقط در سه ماهه دوم یا زایمان زودرس منجر شود، اما معمولاً سقط جنین ناشی از عوامل ایمونولوژیک در سه ماهه نخست بارداری‌ رخ می‌دهد.

عضو تیم تخصصی مرکز درمان ناباروری ابن‌سینا درباره مواردی که لازم است مشاوره ایمونولوژی انجام شود، اظهار کرد: مشاوره ایمونولوژی در موارد سقط مکرر یا شکست مکرر لانه‌گزینی در درمان ناباروری ضروری است. اگر سن خانم زیر ۳۵ سال باشد، پس از سه بار سقط یا شکست لانه‌گزینی و اگر بیش از ۳۵ سال باشد، پس از دو بار سقط یا شکست لانه‌گزینی جنین، مشاوره ایمونولوژی ضروری است.

وی درباره شیوع سقط یا شکست درمان ناباروری ناشی از علل ایمونولوژیک افزود: مطالعات مختلف آمارهای متفاوتی ارائه می‌کنند و حتی برخی مطالعات شیوع ۶۰ تا ۷۰ درصدی سقط ناشی از علل ایمونولوژیک را مطرح کرده‌اند. اما تجربه ما در مرکز درمان ناباروری ابن‌سینا که مرکز ارجاعی سقط مکرر است، نشان می‌دهد که حدود ۳۰ درصد از موارد سقط مکرر ناشی از اختلالات سیستم ایمنی است و سهم این علل در شکست مکرر لانه‌گزینی از این میزان نیز کمتر است.

توکلی علت اصلی شکست مکرر لانه‌گزینی را عوامل جنینی ذکر کرد و توضیح داد: هنگامی که جنین تشکیل می‌شود باید موادی را برای کمک به لانه‌گزینی تولید کند. وقتی جنین این مواد را تولید می‌کند مادر نیز در پاسخ موادی را تولید می‌کند تا لانه‌گزینی اتفاق افتد. در واقع انگار باید همان ابتدا نوعی مکالمه بین جنین و مادر شکل بگیرد تا لانه‌گزینی و بارداری رخ دهد. در اغلب موارد شکست لانه‌گزینی ناشی از این است که یا جنین آن مواد را تولید نمی‌کند یا مادر پاسخ نمی‌دهد. ممکن است ما  بلاستوسیست پا جنین با گرید A داشته باشیم که ظاهر و رشد بسیار خوبی دارد، اما لزوماً نمی‌تواند آن مواد لازم برای لانه‌گزینی را تولید کند.

وی در ادامه خاطرنشان کرد: اختلال سیستم ایمنی یا خودایمنی لزوماً به معنی ضعف سیستم ایمنی یا بیماری نیست. سیستم ایمنی بدن به‌طور طبیعی نسبت به عوامل بیگانه و خارجی واکنش نشان می‌دهد، اما گاه ممکن است اشتباه کند و علیه قسمت‌هایی از بدن، فعالیت کند و در چنین مواردی ما با یک اختلال سیستم ایمنی مواجه‌ایم. تأکید بر این نکته ضروری است که خودایمنی همیشه به معنی بیماری نیست، مگر وقتی که در عملکرد یک عضو اختلال ایجاد کند، مانند بیماریهای روماتیسمی. در واقع در بسیاری از موارد اختلال سیستم ایمنی بر اساس شرح حال و آزمایشات کشف می‌شود، بی آنکه فرد هیچ علامتی داشته باشد و چه بسا اگر قصد بارداری نداشته باشد، هرگز متوجه آن نشود.

وی درباره علل بروز اختلالات ایمونولوژیک، عنوان کرد: اختلالات سیستم ایمنی علت واحد و مشخصی ندارند و مجموعه‌ای از عوامل، از جمله زمینه ژنتیکی، فاکتورهای محیطی و سبک زندگی می‌توانند در بروز این اختلالات اثرگذار باشند. همچنین، وضعیت روحی و استرس‌ها هم می‌توانند در این زمینه نقش داشته باشند.

عضو تیم تخصصی مرکز درمان ناباروری ابن‌سینا در ادامه یادآور شد: در برخی موارد اختلالات ایمنی با اختلالات انعقادی یعنی لخته شدن خون همراه است. در خون پروتئین‌هایی وجود دارد که ایجاد لخته می‌کنند و همزمان پروتئین‌هایی وجود دارد که لخته را حل می‌کنند و مانع تشکیل آن می‌شوند. این دو دسته از پروتئین‌ها در یک هارمونی و تعادل، دائماً در حال فعالیت‌اند، اما گاه به دلایلی همچون تغییرات هورمونی در بارداری ممکن است از تعادل خارج شوند. این از دست رفتن تعادل در خانم‌هایی که مستعد اختلالات انعقادی هستند، باعث بروز لخته می‌شود. اگر این لخته‌ها همان ابتدا ایجاد شود، مانع لانه‌گزینی جنین می‌شود و اگر دیرتر، در جفت تشکیل شود، مانع خون‌رسانی به جنین و در نتیجه باعث سقط جنین می‌شود.

این متخصص ایمونولوژی درباره زمان و روند انجام مشاوره ایمونولوژی، تصریح کرد: همان‌طور که گفته شد، در خانم‌های زیر ۳۵ سال پس از سه بار سقط یا شکست لانه‌گزینی و در خانم‌های بالای ۳۵ سال پس از دو بار سقط یا شکست لانه‌گزینی، مشاوره ایمونولوژی انجام می‌شود. این مشاوره و بررسی نیز باید دست‌کم یک ماه و نیم پیش از اقدام به بارداری یا انتقال جنین انجام شود تا ما بتوانیم بررسی‌های لازم را انجام دهیم و بر اساس نتایج، سیستم ایمنی بدن مادر را برای بارداری تنظیم و آماده کنیم. اساس مشاوره بر دریافت یک شرح حال دقیق و کامل از خانم است. بر اساس این شرح حال ما به سرنخ‌هایی دست می‌یابیم تا بتوانیم آزمایشات لازم را درخواست کنیم. این مرحله بسیار مهم است، زیرا آزمایشات ایمونولوژی طیف گسترده‌ای را شامل می‌شود و ما بر اساس یک شرح حال دقیق و درست، می‌توانیم فقط آزمایشات لازم و مرتبط را درخواست کنیم. همچنین، داشتن یک شرح حال درست در انتخاب رویکرد درمانی و داروها هم بسیار تعیین‌کننده است و به ما کمک می‌کند تا بتوانیم عوارض دارویی را کنترل کنیم. بنابراین، مهم است که بیمار با دقت و تمرکز به پرسش‌های ما پاسخ دهد.

توکلی درمان را وابسته به شرایط هر فرد دانست و گفت: ما بر اساس شرح حال و نتایج آزمایشات به تشخیص می‌رسیم و متناسب با شرایط هر فرد داروهای لازم را تجویز می‌کنیم. مصرف داروها باید یک ماه قبل از اقدام به بارداری یا انتقال جنین آغاز شود تا ما بتوانیم سیستم ایمنی و انعقادی مادر را برای پذیرش جنین تنظیم و آماده کنیم. البته، در مواردی که خانم بیماری خودایمنی دارد، مانند بیماریهای روماتیسمی یا ام اس، حتماً باید اجازه بارداری از سوی پزشک متخصص در زمینه آن بیماری هم داده شود. زیرا تغییرات هورمونی بارداری ممکن است باعث فوران یا تشدید بعضی از بیماری‌های خودایمنی شود، بنابراین لازم است بر اساس نوع بیماری، متخصص مربوطه شرایط خانم را بررسی و امکان بارداری او را تأیید کند.

بنابر اعلام روابط عمومی مرکز درمان ناباروری ابن سینا، وی در پایان خاطرنشان کرد: خوشبختانه مرکز درمان ناباروری ابن‌سینا نخستین مرکز درمان ناباروری در کشور است که در زمینه کاربرد بالینی ایمونولوژی در درمان سقط مکرر و شکست مکرر لانه‌گزینی فعالیت داشته است و خوشبختانه در مواردی که سقط مکرر صرفاً ناشی از اختلالات ایمنی باشد، آمار موفقیت درمان در مرکز ابن‌سینا بیش از ۸۷ درصد است. البته مرکز ابن‌سینا یک مرکز جامع است و از آنجا که سقط جنین معمولا چندعاملی است، ما همواره بیماران را  از جنبه‌های گوناگون ایمونولوژی، ژنتیک، غدد و ..‌. بررسی می‌کنیم و صرفا به یک جنبه اکتفا نمی‌کنیم.

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