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A subject with recurrent pregnancy loss
comes to you in different ways and in different phases. She may
come to you for evaluation after the loss or she may come to you
when pregnant again. In both these phases endosongraphy has a
vital role to play.
Let us see this clinical situation: Mrs.. A., 23 years female
presents with H/o three consecutive pregnancy losses. How will
you evaluate her case? Vital points to be asked in this case are
:
a) Are these pregnancies confirmed preferably on USG
b) At what weeks did she abort.
c) Were these live abortions or dead abortions. With each answer
the approach changes:
If the pregnancies were not confirmed they might not be
pregnancies at all. It is then not a case of spontaneous
abortion but a case of anovulation. The entire approach now
changes. If these were abortions confirmed – then ask as to
whether they were live or dead if they were live abortions then
there is a strong possibility of anatomical cause. If anatomical
cause is suspected Endosongraphy helps you to identify the cause
brilliantly. It should now be remembered that I trimester losses
could be immunological as well. These are easy to investigate
and a request for antiphospholipid antibody is warranted. If
this is negative, chromosomal evaluation of Mrs. A, and Mr. is
to be taken up now.
Mrs. B, G4 P0 H/o amenorrhea 5 weeks presents with H/o
immunological losses How to manage this pregnancy.
This is the time to check for the following features:
Chorionic Clarity
- Early chorionic sac before appearance of
yolk sac 3-5 mm
- Grows by 1-2 mm / day
- Abnormal chorionic sac Õ miscarriage rate Õ 11.5 %
Yolk Sac :
Predictor of abnormalities when:
* Size < 2mm or > 5.6 mm.
* Not appeared with MSD > 8 mm
* Solid echogenic appearance
* Asymmetry, crenation, flattening of yolk sac : present.
* Sensitivity as predictor of outcome only 15.6 % .
* Abnormal sonographic appearance associated with fetal
pathologies such as chromosomal abnormalities, partial molar
pregnancy, and omphelocoele.
Yolk Sac - Significance
1) Large yolk sac ( > 5-7 mm dia )
2) Small yolk sac ( < 2 mm dia )
3) Irregular or enfolded ( Perhaps reflects sac collapse )
4) Free floating
5) Calcification or yolk sac .
The entire above are the signs of embryonic demise and often
precede the fall in HCG levels.
Subchorionic Hemorrhages
* Result from abruption of placental margin or marginal sinus
rupture.
* Predominant hemorrhage often remote from placenta
* Acute hemorrhage usually hyperechoic / isoechoic relative to
placenta Þ becomes sonolucent in 1 to 2 weeks.
*Identification of subchorionic hemorrhage associated with :
60-70 % continuation rate with a positive CA .
Embryonic Heart Rate
Progressively increases from 110 beats per min at 5.5. wks. (CRL
3-4 mm) to 171 - 178 beats per/ mt. at 8 wks. (CRL 15 mm). At 9
wks embryonic heart rate reaches a plateau ranging 160 - 190
beats per min. It continues in this range into the second
trimester slowing then to the 120 - 160 beats per minute range.
Embryonic bradycardia is considered as a sign of impending fetal
loss.
EHR < 85 beats per minute (+- 2 SD) was taken to be sign of
impending fetal loss.
Sensitivity of
1) Abnormal EHR in predicting fetal loss - 65 %
2) Normal EHR predicated ( N) outcome - 98 %.
A rapid EHR:
2 possible explanations :-
1) Embryo smaller than it should be reflecting its reduced
growth capacity.
2) EHR > 200 may reflect infection
C.R.L.:
A CRL - gestational sac diameter mismatch is a sign of impending
fetal demise.
Slow rate of CRL growth is suggestive of impending fetal demise.
Amniotic Sac:
Failure of the amniotic sac to grow in all directions toward the
chorion.
Gestational Sac:
Irregular outline of gestational sac .
Empty gestational sac.
> 16 mm diameter by TAS
> 8 mm diameter by TVS
Treatment protocol established in these cases was according to
the degree of positivity. We classified <10 GPL as negative,
10-20 as weakly positive, 20 to 100 as moderately positive and
more than 100 as strongly positive. For weak and moderate
positive cases, we gave low dose aspirin 1.2 mg/kg./day in the
interval period. Than allowed a conception. We restarted aspirin
at 12 weeks and went on to give for 36 weeks. In strong positive
cases we gave prednisolone in a dose of 10-20 mg/day for three
months in the interval period allowed a conception and then
started aspirin in the some dose from 12 weeks to 36 wks.
Colour Doppler also helps in this:
Following qualitative observations
documented on colour doppler
Abnormal Pregnancy Trophoblastic flow
Corpus luteum flow
Embryonic demise Poor of
absent
Normal
Anembryonic
Normal
Normal
Pregnancy.
Deficient CL
Normal
Poor or absent
Chromosomal
Normal
Normal
Abnormality
Mrs. D, G4-P0 has immunological causes of
these pregnancy losses. Last time she did not respond to the
treatment protocol. She is now fitting into those 8-11 % cases,
who are of refractory APA. Continuous aspirin therapy is now a
days being recommended for this.
K Mrs. E, G4 P0, presents with anatomical
cause for losses treated surgically. How to manage this
pregnancy.
The optimal treatment for uterine anomalies is still a matter
of debate. Open surgical correction of congenital anomalies has
been reported to give successful subsequent pregnancy outcome
but may be associated with significant postoperative infertility
of pelvic adhesions.
Value of treatment in recurrent pregnancy loss
Majority of studies of RPL on uterine anomalies are without
control, comparing miscarriage rate before and after
treatment in the same woman. Interpretation of results - flawed.
Hysteroscopic techniques are attractive, but results from
randomized control studies are lacking. Cervical incompetence -?
Over diagnosed.
Thus Endovaginal sonography has completely changed our approach
and management to cases of R.P.L. and will continue to do so in
the decades to follow
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