Efficacy of Progesterone and Low Molecular Weight Heparin in Recurrent Miscarriages

• Vaginal micronized progesterone (Drug): Vaginal micronized progesterone 800 mg daily administered in two divided doses .
• Enoxaparin (LMWH) (Drug): Administered subcutaneously once daily at a weight-adjusted prophylactic dose according to body weight or applicable local guidelines.

Primary outcomes

• Live Birth Rate [At delivery (≥24+0 weeks of gestation)]: Proportion of randomized participants who deliver at least one live-born infant at ≥24+0 weeks of gestation.

Secondary outcomes

• Ongoing Pregnancy Rate at 22 Weeks [From enrollment to the end of 22 weeks of the index pregnancy.]: Proportion of randomized participants with an ongoing intrauterine pregnancy at 22+0 weeks of gestation, confirmed by ultrasound demonstrating fetal cardiac activity.
• Maternal Complications [From enrollment to the end of treatment at 6 weeks post-labor.]: Incidence of pregnancy-related complications, including preeclampsia (defined by ISSHP), gestational hypertension, gestational diabetes, placental abruption, postpartum hemorrhage (defined as estimated blood loss >500 mL following vaginal delivery or >1000 mL following cesarean section).
• Neonatal Outcomes: [From enrollment to the end of treatment at 6 weeks post-labor.]: Birth weight (grams), APGAR scores at 1 and 5 minutes post-delivery (APGAR at 10 minutes may be recorded if available), admission to neonatal care unit (NICU), and presence of congenital anomalies confirmed postnatally.
• Safety of the trial medication [From enrollment to the end of treatment at 6 weeks post-labor.]: Incidence of major bleeding events (overt bleeding requiring transfusion, surgical intervention, or hemodynamic intervention) and minor bleeding events (mucosal or injection-site bleeding), thrombocytopenia (defined as platelet count <100,000/μL), hypersensivity, and injection-site reactions.
• Adherence and Tolerability: [Treatment discontinuation: from initiation at 5-7 weeks' gestation to 36+0 weeks or delivery. Pain and missed-dose outcomes: assessed at 20 and 34 weeks' gestation and 6 weeks postpartum.]: Treatment discontinuation rate and reasons for discontinuation (including adverse events); participant-reported injection-site pain associated with LMWH treatment, assessed using a numerical rating scale from 0 (no pain) to 10 (worst imaginable pain); participant-reported missed doses of study treatment and reasons for missed doses; and completeness of medication diaries.

Sex: Female, ages: 18 Years to 40 Years

Inclusion Criteria:

* History of ≥2 consecutive unexplained miscarriages before 20 weeks of gestation.
* Confirmed intrauterine pregnancy by ultrasound and/or serum β-hCG (≥5 weeks).
* Willingness to follow study procedures (progesterone use, possible daily - injections) and provide written informed consent.
* No medical contraindication to progesterone or LMWH.

Exclusion Criteria:

* Documented antiphospholipid syndrome or any current anticoagulant requirement.
* Anatomical abnormalities (e.g., significant uterine malformations, large fibroids) conclusively linked to RPL.
* Known hypersensitivity to enoxaparine or heparins, or prior heparin-induced thrombocytopenia (HIT).
* Use of systemic steroids (beyond standard pregnancy doses) for other immunological or inflammatory conditions.
* Severe renal insufficiency (eGFR <30 mL/min), advanced liver disease, or other clinically significant systemic autoimmune disease (e.g., systemic lupus erythematosus, rheumatoid arthritis) that may affect pregnancy or study compliance.
* Inability or unwillingness to comply with study requirements (language barriers, severe psychiatric conditions, etc.).
* Abnormal karyotype

• Clark P, Walker ID, Langhorne P, Crichton L, Thomson A, Greaves M, Whyte S, Greer IA; Scottish Pregnancy Intervention Study (SPIN) collaborators. SPIN (Scottish Pregnancy Intervention) study: a multicenter, randomized controlled trial of low-molecular-weight heparin and low-dose aspirin in women with recurrent miscarriage. Blood. 2010 May 27;115(21):4162-7. doi: 10.1182/blood-2010-01-267252. Epub 2010 Mar 17. PMID 20237316
• Gris JC, Mercier E, Quere I, Lavigne-Lissalde G, Cochery-Nouvellon E, Hoffet M, Ripart-Neveu S, Tailland ML, Dauzat M, Mares P. Low-molecular-weight heparin versus low-dose aspirin in women with one fetal loss and a constitutional thrombophilic disorder. Blood. 2004 May 15;103(10):3695-9. doi: 10.1182/blood-2003-12-4250. Epub 2004 Jan 22. PMID 14739212
• Coomarasamy A, Williams H, Truchanowicz E, Seed PT, Small R, Quenby S, Gupta P, Dawood F, Koot YE, Bender Atik R, Bloemenkamp KW, Brady R, Briley AL, Cavallaro R, Cheong YC, Chu JJ, Eapen A, Ewies A, Hoek A, Kaaijk EM, Koks CA, Li TC, MacLean M, Mol BW, Moore J, Ross JA, Sharpe L, Stewart J, Vaithilingam N, Farquharson RG, Kilby MD, Khalaf Y, Goddijn M, Regan L, Rai R. A Randomized Trial of Progesterone in Women with Recurrent Miscarriages. N Engl J Med. 2015 Nov 26;373(22):2141-8. doi: 10.1056/NEJMoa1504927. PMID 26605928
• Ectopic pregnancy and miscarriage: diagnosis and initial management. London: National Institute for Health and Care Excellence (NICE); 2023 Aug 23. Available from http://www.ncbi.nlm.nih.gov/books/NBK544906/ PMID 31393678
• Coomarasamy A, Devall AJ, Cheed V, Harb H, Middleton LJ, Gallos ID, Williams H, Eapen AK, Roberts T, Ogwulu CC, Goranitis I, Daniels JP, Ahmed A, Bender-Atik R, Bhatia K, Bottomley C, Brewin J, Choudhary M, Crosfill F, Deb S, Duncan WC, Ewer A, Hinshaw K, Holland T, Izzat F, Johns J, Kriedt K, Lumsden MA, Manda P, Norman JE, Nunes N, Overton CE, Quenby S, Rao S, Ross J, Shahid A, Underwood M, Vaithilingam N, Watkins L, Wykes C, Horne A, Jurkovic D. A Randomized Trial of Progesterone in Women with Bleeding in Early Pregnancy. N Engl J Med. 2019 May 9;380(19):1815-1824. doi: 10.1056/NEJMoa1813730. PMID 31067371
• Christiansen OB, Nybo Andersen AM, Bosch E, Daya S, Delves PJ, Hviid TV, Kutteh WH, Laird SM, Li TC, van der Ven K. Evidence-based investigations and treatments of recurrent pregnancy loss. Fertil Steril. 2005 Apr;83(4):821-39. doi: 10.1016/j.fertnstert.2004.12.018. PMID 15820784
• ESHRE Guideline Group on RPL; Bender Atik R, Christiansen OB, Elson J, Kolte AM, Lewis S, Middeldorp S, Mcheik S, Peramo B, Quenby S, Nielsen HS, van der Hoorn ML, Vermeulen N, Goddijn M. ESHRE guideline: recurrent pregnancy loss: an update in 2022. Hum Reprod Open. 2023 Mar 2;2023(1):hoad002. doi: 10.1093/hropen/hoad002. eCollection 2023. PMID 36873081