spontaneous abortion associate professor iolanda blidaru md, phd
TRANSCRIPT
SPONTANEOUS ABORTION
ASSOCIATE PROFESSOR IOLANDA BLIDARU
MD, PhD
DefinitionsThe termination of pregnancy by any means
before the fetus is sufficiently developed to survive.
USA and western European cuntries → the termination of pregnancy before 20 weeks gestation based upon the date of the first day of the LMP.
Another commonly used definition: delivery of product of conception that weighs less than 500g.
In some European countries, including Romania, this definition is confined to the interruption of pregnancy before 24 weeks of gestation, less than l000g (dead) or less than 500g (alive).
Frequency
Approximately 15% to 20% of clinically
recognized pregnancies are aborted
spontaneously.
Abortions
45% in the weeks 5 to 9
35% in the weeks 10 to 14
15% in the weeks 15 to 18
Classification
unique (isolated) or recurrent (3 or more consecutive spontaneous abortions)
early abortions (before 12 weeks) or late abortions (in the 2nd trimester)
threatened, inevitable (or in evolution), incomplete, missed and complete abortion
Etiology
Mechanisms responsible for abortion
I.- mechanical causesII.- infectionsIII.- genetic causesIV.- endocrine causesV.- immunological causesVI.- maternal systemic conditions
I. Mechanical causes
ovular (multiple pregnancy, hydramnios)
uterine defects:
1. - congenital anomalies
2. - uterine malposition (retroversion)
3. - uterine tumors (myomas)
4. - intrauterine adhesions synechiae (Asherman syndrome)
5. - incompetent cervix
II. Infections
Microorganisms associate with spontaneous abortion: - variola - malaria - CMV - Toxoplasma - Mycoplasma hominis - Chlamydia trachomatis - Salmonella typhi - Ureaplasma urealyticum
III. Genetic causes
abnormality of development of the zygote, embryo, fetus and/or the placenta
aneuploidy (abnormal no. of chromosomes )
euploidy (abnormal chromosom component)
Aneuploid abortion
~ 50% of clinically recognized pregnancy
loss
Autosomal trisomy → the first trimester
abortions + recurrent abortions.
Monosomy X (45/X) → compatible with live-
born females (Turner syndrome).
Triploidy → associated with hydropic placental
degeneration
Euploid abortion1. chromosomally normal abortuses → in late
pregnancy 2. incidence increased after maternal age of 35
years3. chromosomal structural abnormalities →
(translocations and inversions)isolated mutation or polygenic factorsvarious maternal factorspaternal factors (chromosome translocation in sperm
IV. Endocrine causes
Disturbances in the secretions of reproductive hormones → abnormal trophoblastic function
1.Luteal phase deficiency (LPD) - inadequate progesterone effect on the endometrium - 35% of recurrent pregnancy loss
2.Combined deficiency of E and P → the most common cause
3.Other forms: isolated E insufficiency, isolated P insufficiency, hyperandrogenism
V. Immunological causes
Autoimmune mechanisms antiphospholipid antibodies anticardiolipin antibodies
against platelets and vascular endothelium
vascular damage thrombosis placental destruction
abortion
V. Immunological abortions
Alloimmune mechanisms
The human embryo → an allogenic transplant that is
tolerated / facilitated by the mother.
Several immunological mechanisms - to prevent
fetal rejection:
- histocompatibility factors CMH, HLA-G
- circulating blocking factors
- local supressor factors
- maternal or antipaternal anti-
leukocytotoxic antibodies
VI. Maternal systemic conditions
1. endocrine disorders
2. blood group incompatibility (ABO, Rh)
3. toxic factors (cocaine, alcohol, cigarette smoking)
4. psychic or emotional causes, advanced maternal age, poor socio economic status, protein and vitamin under-nutrition
5. Cardio-vascular-renal hypertensive disorders
Clinical stagesA. Threatened abortion
Symptoms - bleedingspotting of bright blood
dark brown discharge
- cramping pain
- no changes in the cervix Usually, bleeding begins first and cramping abdominal pain follows (hours to several days). Differential diagnosis - ectopic pregnancy - dysfunctional uterine bleeding - uterine fibro-myomas - hydatidiform mole - benign lesions / invasive cancer
Clinical stages B. Inevitable abortion
Symptoms
- abdominal and back pain
- severe bleeding
- open cervixDuring first 2 months, abortion - 1 stage.
During the 2-nd trim., abortion - 2 stages:
1. rupture of the membranes + fetal expulsion;
2. incomplete expulsion of the placenta
Clinical stagesC. Incomplete abortion
In the majority of spontaneous abortions variable amounts of placental tissue may remain within the uterus (attached to the wall or lying free in the cavity). Bleeding - during or following abortion may be life-threateningprofuse → massive (→ hypovolemia)severepersistent
Sepsis - in cases with criminal or self- induced abortion.
Clinical stagesD. Missed abortion
retention of dead conceptus in utero for several weeks
E. Complete abortion
the uterus empties itself completely (fetus, fetal membranes, the placenta, the
decidua). This is possible only during the first 6 weeks.
Avortul – forme clinice
Treatment
accurate evaluation
1.pelvic examination visual and digital examination
of the cervix + bimanual palpation of the uterus and
of the adnexa.
2.the degree of cervical effacement and dilation -
determined by palpation.
3.Ultrasonic scanning (a normal-appearing sac+
normal embryo/fetus - favorable prognosis).
4.Serial beta-HCG
TreatmentThreatened abortion → treated at home / hospitalized.
Medical treatment - progesterone / synthetic progestational agents, i.m. or orally.
Inevitable abortion → surgical uterine evacuation (with suction technique or surgical procedure) + reducing blood loss and pain.
Incomplete abortion → surgical uterine evacuation because of the risk of infection and/or continued and excessive bleeding.
Missed abortion → surgical uterine evacuation Infected abortion → the operation should be delayed,
unless excessive uncontrolled blood loss, and antibiotics are administered.
TreatmentCervical incompetence → CERCLAGE
= surgical treatment, consisting of reinforcement of the cervix by some type of purse string stitches; best performed after the first trimester (14 weeks) but before cervical dilatation of 2 to 3 cm is reached.
Bleeding, uterine contractions or ruptured membranes are contraindications to this surgery.
The Mc Donald procedure = suture of monofilament placed in the cervix to encircle the internal os (less traumatic with reduced blood loss).
INCOMPETENT CERVIX
TreatmentAsherman syndrome treatment = lysis of
the adhesions via hysteroscopy and placement of an IUD to prevent recurrence of synechiae. Continuous high-dose estrogen therapy for 60 to 90 days.
Lupus erythematosus - Successful pregnancies with low-dose aspirin (inhibit thromboxane production by damaged platelets and endothelium).
Antiphospholipid syndrome – Heparin (to inhibit thrombosis) + corticosteroids (to suppress antibodies as well as to inhibit their action on target antigen).
Immunotherapy - highly controversial.