Successful Management Of Essential Thrombocytosis In Pregnancy

Author Information

Tagad M*, Tiwari N**, Chaudhari HK***.
(* Junior Resident, ** Assistant Professor, *** Associate Professor, Department of Obstetrics and Gynecology, Seth G S Medical College and K E M Hospital, Mumbai, India.)


Patients with essential thrombocythemia (ET) are mostly women. Some of them are diagnosed at childbearing age. Decision making on pregnancy is a common issue in the clinical management of women with ET. There is limited information regarding the outcome of pregnancy in patients with ET. We report here one case with ET in a pregnant woman at our institute.


Essential thrombocythemia (ET) is a chronic myeloproliferative disorder with an increased risk of vascular complications.[1] It is a clonal expansion of multipotent stem cells.Thrombocytosis is a part of ET and is also found in 50 % of patients with polycythemia vera and 35 % patients of chronic myeloid leukemia. Similar to idiopathic thrombocytopenia of pregnancy, ET is also a diagnosis of exclusion once other reasons for thrombocytosis such as reactive thrombocytosis, myelodysplastic syndrome (MDS) and other myeloproliferative neoplasms (MPN) have been eliminated. Pregnancy with essential thrombocythemia are at high risk of spontaneous abortion and other pregnancy complications. Live birth rate of pregnancy is 50 %-70 % and abortion rate is 25- 50 %.[2]

Case Report

A 30 years old gravida 4 with 1 prior spontaneous abortion and 1 prior sudden term intrauterine fetal demise at 36 weeks of gestation with bad obstetric history diagnosed with essential thrombocytosis due to JAK2 mutation was admitted with us. Bone marrow  examination done in view of bad obstetrics history in first trimester was suggestive of    JAK2 mutation and she was started on tablet aspirin 75 mg daily and injection low molecular weight heparin 0.6 cc subcutaneous (s.c.) daily in the first trimester. Injection Interferon α -2 β (3mu) s.c. once a week was advised from second trimester of pregnancy if platelet count was less than 4.5 lakhs/ μl. Her general condition was fair. On per abdomen examination uterus was 36 weeks, cephalic presentation, FHS were present and uterus was relaxed On per vagina examination her cervical os was closed.
Hematologist was consulted for peripartum management. She was advised complete hemogram. Her platelet count was 4.01 lakhs/ μl. Her leucocyte count was 10,100 cells/ Her coagulation profile was normal. Thombophilia profile was negative. Her obstetrics scan at term was suggestive of mild IUGR and mild oligohydramnios. She was advised to stop tablet aspirin at 37 weeks of gestation but continue injection LMWH 0.6 cc s.c. daily till 24 hours prior to delivery subsequently to restart it after achieving complete hemostasis post delivery till 6 weeks postpartum. Injection Interferon α 2 β 3 mu s.c. once a week was continued weekly. She went in labor spontaneously at 39 weeks of gestation. Injection LMWH was stopped. Labor was monitored as per protocols. She delivered a female child of 3.3 kg uneventfully. Injection LMWH was restarted as per advice of hematologist after complete hemostasis.


In ET, platelet count or leucocyte count are not high risk factors for pregnancy complications. The JAK2 mutation was found in 50 % of patients. The JAK2 mutation assessment is a key tool in the diagnostic work-up of patients with chronic myeloproliferative disorders.[1,2] Women having the mutation have higher risk of complication during pregnancy; like abortion, intrauterine fetal retardation and still birth. However, pregnancy is not contraindicated in a patient with essential thrombocytosis.
Complete hemogram is must in these cases. Bone marrow examination is the diagnostic test. Thrombophilia profile is recommended in the evaluation of a woman of childbearing age with ET for therapeutic interventions that are aimed at improving pregnancy outcome.[3]
Regarding treatment of ET during pregnancy, cytoreduction therapy is used to reduce the risk of bleeding. Hydroxyurea is the first-line medication for cytoreduction but it should be avoided in the first trimester because of its known teratogenicity.[5,6]  Interferon is the agent of choice in pregnant women with ET.[5]  Low-dose aspirin during pregnancy has been shown to be safe for the fetus without an increased risk of bleeding for the mother.[7] Aspirin is a very common drug used in patients with ET who do not have a history of bleeding.[8] Interferon inhibits the growth of megalokaryocytic progenitors in patient with essential thrombocythemia resulting in platelet reduction. Aspirin is also helpful for the same.


In patient’s with essential thrombocytosis, pregnancy may evolve uneventfully in most of these patient’s with proper management. Women with JAK2 mutation can have various adverse events during pregnancy like growth restriction, fetal loss and maternal complications like gestational diabetes, pregnancy induced hypertension, bleeding, and   abruptio placentae

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Tagad M, Tiwari N, Chaudhari HK. Successful management of Essential thrombocytosis in pregnancy. JPGO 2019. Volume 6 No.4. Available from: