Ultrasonography in In Vitro FertilizationRoger A. PiersonDepartment of Obstetrics, Gynecology pptx

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Ultrasonography in

In Vitro Fertilization

Roger A. Pierson

Department of Obstetrics, Gynecology and Reproductive Sciences,

College of Medicine, University of Saskatchewan, Royal University Hospital,

Saskatoon, Saskatchewan, Canada

Imaging has become such an integral part of clinical care in the assisted

reproductive technologies that it is difficult to imagine how in vitro fertiliza￾tion (IVF) was done before we had the ability to visualize the ovaries and

uterus easily. Recall that IVF was once done using laparoscopic retrieval

of oocytes following ovarian stimulation cycles monitored only by hormonal

assay of systemic estradiol levels, that embryos were transferred back into a

uterus when we had no real idea about the physiologic status of the endo￾metrium, and only a clinical touch was used to guide the placement of the

embryo transfer catheter. Easily accessible, and easy-to-use, ultrasono￾graphic imaging in the hands of the individuals performing the assisted

reproductive technology (ART) procedures has delivered us from those

uncertainties. The quality and quantity of the information we received from

the ultrasonographic images that are now an essential part of every pro￾cedure have been a very important aspect of the incredible increases in

ART success rates we have seen over the past decade. It is important to

remember that the integration of enhanced understanding of anatomy,

physiology, endocrinology, and pathology we have gained with imaging in

the patients undergoing IVF are as important as the fantastic increase

in knowledge in the embryo laboratories. The confluence of technologies

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we now used in ART care have greatly increased the probabilities of success￾ful pregnancies for our patients.

The purpose of this chapter is to describe the primary uses of ultra￾sound imaging in IVF and to identify some promising new areas where

imaging has the potential to enhance our understanding in assisted repro￾duction. The essentials of ultrasonography in IVF are in monitoring the

course of ovarian stimulation protocols, visually guided retrieval of oocytes,

assessment of the endometrium, and visually guided embryo transfer. Each

of these areas also provides a springboard for new research areas which may

be incorporated into clinical care. Awareness of new frontiers is essential to

progress in ART and in understanding the changes that will surely come.

We rely so heavily on imaging in general gynecology, infertility workup,

and early obstetrical care that it becomes challenging to narrow our focus

to only IVF; however, with the general caveat that ultrasonography has

forever changed our understanding of female reproduction, my goal is to

provide a synopsis of imaging in IVF integrated into a framework within

which we provide the highest quality of care for the patients who require

ART to complete their families.

OVARIAN ASSESSMENT

Monitoring the Course of Ovarian Stimulation

Ovarian stimulation protocols vary tremendously and have evolved

from fairly simplistic administration of exogenous hormones derived from

urinary sources to quite sophisticated blends of gonadotrophin-releasing

hormone (GnRH) analogs, recombinant follicle-stimulating hormone

(FSH), luteinizing hormone (LH), and other compounds. The common

denominator in all ovarian stimulation protocols is that ultrasonography

is used to determine their effects on the ovaries of each patient. All the

protocols have been designed to override the physiologic mechanism

of selection of a single dominant follicle, obviate atresia in the cohort of

follicles recruited into the follicular wave, and foster and sustain the devel￾opment of many follicles to an imminently pre-ovulatory state so that

properly matured oocytes may be retrieved for IVF. Ultrasonography is

essential in determining the numbers and fates of individual follicles stimu￾lated by exogenous gonadotrophins. Toward this end, the follicular

response of each woman to the stimulation protocol and the number of

oocytes desired and clinical assessment of the risk of ovarian hyperstimula￾tion will dictate increasing or decreasing daily doses of gonadotrophins. It is

important to note that the expected linear relationship between circulating

estradiol concentrations and follicular diameter may not exist during

ovulation induction. Similarly, we understand that all follicles probably

do not contribute equally to the concentrations in the systemic circulation.

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