Clinical Research UNIVERSITAS PELITA HARAPAN 42 Comparison Of Progesterone-Induced Blocking Factor Serum Levels In Preterm Labor And Preterm Pregnancy Patrick Bayu 1 , Johanes C. Mose 2 , Muhammad Alamsyah 2 1 Departemen Obstetri Dan Ginekologi Fakultas Kedokteran UPH / Siloam Hospitals Karawaci 2 Departemen Obstetri Dan Ginekologi Fakultas Kedokteran Universitas Padjadjaran / RS Hasan Sadikin Bandung ABSTRAK Persalinan kurang bulan merupakan fenomena multifaktor yang melibatkan proses inflamasi yang akan mempengaruhi keseimbangan imunologis rasio Th1 terhadap Th2 yaitu meningkatkan dominansi sitokin proinflamasi Th1 dan juga memicu terjadinya functional progesterone withdrawal. Progesteron berguna dalam mempertahankan uterus selama kehamilan dalam keadaan relaksasi dan proses persalinan dipicu oleh progesterone withdrawal. Selain itu, progesteron mempunyai efek antiinflamasi dan imunomodulator. Meskipun telah diduga bahwa efek progesteron pada tatalaksana persalinan kurang bulan dihubungkan dengan efek antiinflamasinya, namun mekanisme kerja yang spesifik belum diketahui secara pasti. Efek biologis progesteron diperantarai oleh protein berukuran 34 kDa yang dikenal sebagai progesterone-induced blocking factor (PIBF) yang disintesis oleh limfosit wanita hamil yang sehat di bawah pengaruh progesteron. PIBF akan menghambat produksi asam arakidonat, mengurangi aktivitas sel NK, dan memodulasi keseimbangan sitokin. Penelitian ini merupakan penelitian analitik komparatif dengan desain potong silang yang membandingkan kadar PIBF serum antara persalinan kurang bulan dengan kehamilan kurang bulan. Setiap kelompok terdiri atas 16 orang yang memenuhi kriteria inklusi yang berobat ke RSUP Dr. Hasan Sadikin Bandung serta rumah sakit jejaring, berlangsung dari bulan Juli- November 2013. Kadar PIBF serum diukur dengan menggunakan teknik enzyme-linked immunosorbent assay (ELISA). Terdapat perbedaan bermakna antara kadar PIBF serum persalinan kurang bulan (1021,162 ± 391,4051 ng/mL) dengan kehamilan kurang bulan (1297,675 ± 174,2165 ng/mL) dengan nilai p = 0,029. Disimpulkan bahwa kadar PIBF serum persalinan kurang bulan lebih rendah dibandingkan pada kehamilan kurang bulan. Kata kunci : PIBF, persalinan kurang bulan, progesteron ABSTRACT Preterm labor is a multifactorial phenomenon involving inflammatory processes that will affect the balance of Th1 to Th2 by increasing dominance of pro-inflammatory Th1 cytokines and also lead to functional progesterone withdrawal. Progesterone maintains pregnancy mainly by promoting myometrial quiescence and labor is initiated by progesterone withdrawal. Progesterone also has antiinflammatory properties and as an immunomodulator. While it has been postulated that the effect of progesterone on preterm birth is related to its anti-inflammatory properties, the spesific mechanism of action remains unclear. The biological effects of progesterone are mediated by a 34-kDa protein named the progesterone- induced blocking factor (PIBF). PIBF is synthesized by lymphocytes of healthy pregnant women in the presence of progesterone. PIBF inhibits arachidonic acid production, reduced NK cell activity, and modifies the cytokine balance. The objective of this study was to compare serum concentrations of PIBF of women with preterm labor with those women with normal pregnancy. A comparative analytical study with cross- sectional design was conducted. This study consisted of 16 women in each group. All the subjects met the inclusion criteria and were admitted to the Dr . Hasan Sadikin hospital and it’s district hospital. This study conducted from July until November 2013. Serum PIBF concentrations were measured by enzyme-linked immunosorbent assay ( ELISA) . Mean PIBF concentrations in serum of patients with preterm labor were significantly lower (391.4051 ± 1021.162 ng/mL ) than in those of normal pregnancy (174.2165 ± 1297.675 ng/mL) with p = 0.029 . It was concluded that the levels of serum PIBF preterm labor is lower than in normal pregnancy. Keywords : PIBF, preterm labor, progesterone pISSN: 1978-3094 . Medicinus. 2018; 7 (2) : 42 - 46