This document discusses follicular monitoring, which is used to track the growth of ovarian follicles using ultrasound. It is a vital part of assessing IVF and IUI cycles. Regular monitoring allows doctors to evaluate response to medication, adjust doses as needed, and time ovulation or procedures. Early in the cycle, several follicles are recruited and a dominant follicle is selected, growing larger each day. Monitoring involves tracking follicle size and number as well as blood flow. It helps determine when to trigger ovulation or collect eggs and can identify patients at risk for overstimulation.

1. Follicular Study/Monitoring
Prepared by Dr Vrishit
Guided by Prof. Dr Dharmraj

2.  Ovulation was initially monitored by
conventional methods like BBT,mid luteal
serum progesterone and urinaryLH.
 Nowadays, USGis used for follicular
monitoring for both natural and stimulated
cycles.

3. Follicular monitoring
 Vital component of IVF/IUI assessment and
timing
 Employs a simple technique of assessing
ovarian follicles on regular intervals, and
documenting the pathway of ovulation.

4. WHYTO MONITOR?
 Toevaluate if the dose being used is optimal
 Toadjust the dose of the drug assome
patients arehyperresponsive and some are
poor responders
 Tofind optimal time for ovulation induction
 Totime IUI
 Toavoid exessive stimulationand prevent
OHSSand multiple pregnancy

5. HOW TO MONITOR?
 By ultrasound, color doppler, power doppler-
morphological growth of follicles
 By estradiol alone- indicates functional
activity offollicles
 By both
 TVS–accepted method at all infertility clinics

6. Pathophysiology:
 Journey to ovulation begins during late luteal
phase of prior menstrual cycle, when certain
2-5 mm sized healthy follicles form a
population, from which dominant follicles is
to be selected for next cycle This process is
called 'recruitment'.
 Usual number of suchfollicles may be 3-11,
which goes on decreasing with advancing
age.

8. • During Day 1-5 of the menstrual cycle, a
secondprocessof 'follicular selection' begins,
when among all recruited follicles, certain
growing follicles of size 5-10mm are selected,
while rest of the follicles regress or become
atretic.

10.  During Day 5-7of the menstrual cycle, a
processof 'dominance' begins, when acertain
follicle of 10mm size takes the control and
becomes dominant. This also suppressesthe
growth of the rest of the selected follicles,
and in away, is destined to ovulate.
 This follicle starts growing at rate of 2-3 mm
aday and reaches 17-27mm size just prior to
ovulation .

12. ***
• One important learning point in this regard is,
"largest follicle on day 3of the cycle, may or
may not be a dominant follicle in the end.
Process of dominance begins late, when
suddenly a certain underdog follicle starts
growing faster and suppresses others to
become dominant".

13. • Almost nearing ovulation, rapid follicle
growth takes place, and follicle starts
protruding from the ovarian cortex, attains a
crenated border, and it literally explodes to
release the ovum, along with some antral
fluid.

14. Ul trasound moni tori ng i n
i nduced cycl es, and
predicting success of IVF
 Most of the IVFstudies areconducted after
induction of ovarieswith help of ovulation
inducing agents like Clomiphene citrate. In such
inducedcycle,primarydeterminantsof successare:
 ovarianvolume
 antral folliclenumber
 ovarian stromal bloodflow

15. Ovarianvolume
 is easy to measure,
 although not agood predictor of IVFoutcome.
 alow ovarian volume does not always lead to
anovulatory cycle.
 But, it's important to recognize apolycystic ovarian
pattern and differentiate it from post-induction
multicystic ovaries.
 Follicles arranged in the periphery forming a
'necklacesign', echogenic stroma, and more than 20
follicles of less than 9 mm size, signify apolycystic
pattern ininduced cycle.
 While, follicles in the center aswell asthe periphery,
are seenin normal induced multicystic

16. Antral follicle number
• Antral follicle number of lessthan three,
usually signify possible failure of assisted
reproductive therapy(ART).

17. Ovarian stromalblood flow
• hasbeenrecommended asagoodpredictor of
ARTsuccess.Increasedpeaksystolic velocity (>10
cm/sec)isone of such parameters which hasbeen
advocated.

18. SIGNIFICANCE:
 Helps in prediction of impending ovulation
and optimal timingfor:
 hCGadministration,
 ntercourse, donor orhusband insemination
 egg collection
 If not ovulating can be treated with ovulation
induction agents.

19. Ultrasound follicular monitoring
Serial USGfollicular monitoring is
started from day 7or 8 of the cycle
But in caseof gonadotrophins we start
scanning from 6th day of stimulation.

20. Assessingthe follicular maturity
 Thefolliclesnormally growat arate of 2- 3mm/
dayinastimulatedcycle.
 Definitive sizeof the follicle which confirmsthe
maturity of oocytesisstill controversial.
 Afollicle measuring18—20mm hasbeen found to
contain a mature oocyte.
• Follicular size is measured by taking mean of 2 or
3 largest perpendicular diameters of each follicle .

21. When to administer
gonadotropins?
 Although, its amatter of choice, based on
experienceof individual IVFspecialists, there are
certain parameters which may be considered.
 Minimal criteria suggested is afollicle size of
atleast 15mm, and serum estradiol level of 0.49
nmol/L.
 Better prospects are at follicle sizeof 18mm,
and serum estradiol level of 0.91 nmol/L.
 Random hCGadministration should beavoided3, to
prevent arisk of ovarian hyperstimulation
syndrome (OHSS).

22. Predicting the risk of OHSS
If thereare
more than 4 follicles larger than 16
mm or more than 8 follicles larger
than 12 mm
It is best not to give hCGsoasto prevent
OHSS and high order multiple births.

23. OHSS
 Is a complication ofovarian stimulation
treatment forIVF.
 Rarely, may occurasaspontaneous event in
pregnancy

24. OHSS syndrome consists of
 Weightgain
 Increase in abdominalcircumference
 Ascites
 Pleural effusion
 Intravascular volume depletionwith
hemoconcentration
 oliguria

25. Role of radiologist
 Familiarity with OHSShelps in avoiding the
incorrect diagnosis of ovarian cystic
neoplasm
 Appropriate management canbe timely done
 OHSShasasignificant risk for miscarriage in
early phase after IVF(< 10days after oocyte
retrieval)

26. Fol l i cul ar doppl er f l ow st udi es
 A maturefollicleshows
vascularityinatleast
¾thof thefollicular
circumferenceand
 PSV is 10cm/sec.
 Atthis time LHsurge
startsand
 Thisis therighttimeto
givehCGtrigger

27. Predi ctors of poor ovari an
response are:
 Ovarian volume <3cc
 < 3antral follicles
 Ovarian RI >0.6
 Ovarian PSV < 5cm/ sec
 Suggestpoor ovarian response&
 Higher dosesof gonadotropins willbe
required for stimulation.

28. Ovulation trigger
• The end point of any ovulationinduction
protocol isto indentify the best time for
triggering ovulation.
• In agonadotrophinIn in clomiphene
 Leadingfollicleis
 18 –20mm indiameter
Leadingfollicleis 20–22mm
insize

29. Suggestive of ovulation
 Disappearanceof thefollicle
 Presenceof free fluid in the cul-de-sac.
 Presenceof hyperechoic , smooth
secretary endometrium.

30. Baseline, prior to initiating gonadotropin
stimulation. Ovary with antral follicles

31. Stimulation day 5,showing recruited
follicles measuring 10–12mm

32. Stimulation day 9, showing ovary
with growing follicles

33. Thank You