Recurrent Abortion

DEFINITION:

• A sequence of three or more consecutive spontaneous abortion before 20 weeks.
• It may be primary or secondary (having previous viable birth).
• A woman procuring three consecutive induced abortions is not a habitual aborter.

ETIOLOGY:

FIRST TRIMESTER ABORTION:

Genetic factors (3–5%):

• Most common abnormality is a balanced translocation(25%)

Endocrine and metabolic: 

• Poorly controlled diabetic
• Presence of thyroid autoantibodies
• Luteal phase defect (LPD)
• Polycystic ovary syndrome (PCOS)

Infection:

• Bacterial vaginosis
• Transplacental fetal infection

Inherited thrombophilia:

• Protein C (factor resistance V Leiden mutation)
• Other factors are—deficiencies of protein C, S and antithrombin III
• Hyperhomocystinemia and prothrombin gene mutation

Immune factors (10–15%):

• Autoimmunity:second trimesters
• Antinuclear antibodies, anti-DNA,and antiphospholipid antibodies(lupus anticoagulant ,anticardiolipin antibody, Antibody that cause false positive syphilis test (BFP-ST).
• Alloimmunity—Natural killer (NK) cells
• Parental human leukocyte antigen (HLA)

SECOND TRIMESTER MISCARRIAGE:

Anatomic abnormalities(10–15%)

• Mullerian fusion defects:Unicornuate, bicornuate, septate or double uterus
• Acquired anomalies :
• Intrauterine adhesions, uterine fibroids and endometriosis and cervical

Chronic maternal illness

• Uncontrolled diabetes with arteriosclerosis
• Hemoglobinopathies
• Chronic renal disease. 
• Rh incompatibility
• Inflammatory bowel

SLE

• Infection—Syphilis, toxoplasmosis and listeriosis

INVESTIGATIONS:

Careful history

• The nature of previous abortion process
• Histology of placenta or karyotyping of the conceptus
• Any chronic illness

Diagnostic tests:

• Blood-glucose (fasting and postprandial)
•  VDRL, thyroid function test 
• ABO and Rh grouping 
• Toxoplasma antibodies IgG and IgM.
• Autoimmune screening—lupus anticoagulant and anticardiolipin antibodies
• Prolonged PTT and a normal PT-lupus anticoagulant 
• Serum LH on D2/D3 of the cycle.
• Ultrasonography—to detect congenital malformation of uterus, polycystic ovaries and uterine fibroid.
• Hysterosalpingography in the secretory phase to detect—cervical incompetence, uterine synechiae and uterine malformation
• Karyotyping
• Endocervical swab to detect chlamydia, mycoplasma and bacterial vaginosis.

TREATMENT:

INTERCONCEPTIONAL PERIOD:

• To alleviate anxiety and to improve the psychology
• Hysteroscopic resection of uterine septa, synechiae and submucous myomas
• Uterine unification operation (metroplasty) in bicornuate uterus
• Chromosomal anomalies:PCOS
• Karyotyping of the products of conception
• Counseled for Preimplantation genetic diagnosis (PGD)

PCOS:

• Treatment for insulin resistance, hyperinsulinemia and hyperandrogenemia.
• Metformin therapy
• Control of diabetes and thyroid disorders
• Genital tract infections are treated(doxycycline or erythromycin)

• In cases of recurrent abortions, most common uterine malformation seen is Mullerian fusion defects
• Lupus anticoagulant  is associated with recurrent abortion and isolated prolonged APTT
• Recurrent abortion in 1st trimester is most often due to Chromosomal abnormalities
• Recurrent spontaneous abortions are seen in Uterine pathology,SLE ,Rh incompatibility & Syphilis
• Recurrent abortion in 1st trimester, investigation of choice is Karyotyping
• Hysteroscopy,Parental cytogenetics, Testing Antiphospholipid antibodies & Thyroid function tests are investigation carried out in Recurrent abortion
• Low-dose aspirin is used to treat Antiphospholipid antibody syndrome up to 34 weeks