Spontaneous abortion -What are the possible causes?

Guess, why Pt fainted at Doctors chamber on hearing the list of tests she & her husband has to undergo after 3 spont abortions.

Ms XYZ  & her husband fainted in the Dr Pal’s chamber . She(Ms XYZ)   had had 3 spont abortions.

 She met an old doctor at Kolkata(Dr S K Pal)  to enquire  the possible causes of three successive spont abortions during the gest period 8-10 weeks. What are they known causes of Spontaneous abortion

Spontaneous abortion is defined as pregnancy

terminating before the 20th completed week of gestation.

Approximately 80% of spontaneous abortions

occur in the first trimester. The causes of spontaneous

abortions fall into two categories: genetic and environmental (maternal) as listed next:

A)     Genetic or fetal causes

Trisomy

Polyploidy or aneuploidy

Translocations

B)      Environmental or maternal causes

Uterine

Congenital uterine anomalies

Leiomyoma

Intrauterine adhesions or synechiae (Sherman’s

syndrome)

Endocrine

Progesterone deficiency (luteal phase defect)

Hypothyroidism

Diabetes mellitus (poorly controlled)

Luteinizing hormone hypersecretion (many PCO women).

Immunologic

Autoimmunity: antiphospholipid syndrome, systemic

lupus erythematosus

Infections

Toxoplasma  gondii, Listeria monocytogenes,

Chlamydia trachomatis, Ureaplasma urealyticum,

Mycoplasma hominis, herpes simplex,

Treponema pallidum, Neisseria gonorrhoeae

Dr Pal: What is the commonest cause of spont ab? Ans:-Genetic abnormalities are the most common cause

of spontaneous abortions accounting for almost 50%

to 60% of cases. Autosomal trisomy is the most

frequently identified chromosomal abnormality resulting

in first-trimester abortions. The incidence of

abortions secondary to chromosomal abnormalities

markedly increases after the maternal age of 35 years.

The environmental or maternal causes account for

a small percentage of spontaneous abortions. These include infection; anatomic defects (maternal mullerian

defects); endocrine factors (failure of corpus luteum);

immunologic factors (antiphospholipid antibody syndrome); and maternal systemic disease (diabetes mellitus, hypothyroidism).

How all these gentic/ environmental exert such ill effectsà leading to spont abortion??  Ans:-The most common morphologic finding in early spontaneous abortions is an abnormality of development

of the zygote, embryo, early fetus, or the

placenta.

Clinicians classification:-Spontaneous abortion is clinically classified into threatened, inevitable, missed, incomplete, and complete abortions. Ultrasound findings in abortion

The US findings depend on the developmental

stage of the pregnancy at which the patient presents

with symptoms. Familiarity with normal sonographic

landmarks of first-trimester pregnancy is essential to arrive at a definitive diagnosis.