Ultrasound or sonography has helped revolutionize our approach to  the  infertile patient. Ultrasound machines  are  the  newest addition  to the gynecologist’s bag of tricks; and help  him  to "image"  or see structures in the female pelvis. Ultrasound  uses high frequency sound waves much like SONAR machines used in ships for  detecting  submarines underwater. The high  frequency  sound waves are bounced off the pelvic organs; and the reflected  sound waves  are received by the probe ( transducer) and a computer  is used to reconstruct the waves into black and white images on  the monitor.  Ultrasound machines today are all  real-time  machines, which give dynamic images.

In the old days, ultrasound for infertility was done through  the abdomen. This required you to fill up your bladder ( till it  was ready  to burst !) so that the sound waves could  be  transmitted into the pelvis. However, the standard ultrasound technique today for infertility is vaginal ultrasound ( endovaginal scanning)  in which a long, slim, slender probe is inserted into the vagina and used  for imaging the pelvic organs. Not only is this  much  more comfortable  for  you;  it also gives much  sharper  and  clearer pictures,   since  the  probe  is  much  closer  to  the   pelvic structures.

What  can  you  see on ultrasound ? The  ultrasound  gives  clear pictures of the uterus; and the ovaries. It allows the doctor  to look for fibroids; ovarian cysts; and ectopic pregnancies. It  is also excellent for early diagnosis of pregnancies. However, the ultrasound scan is not very good for assessing whether or not the tubes are normal.

Ovulation scans allow the doctor to determine accurately when the egg  matures;  and  when you ovulate. This is  often  the  basic procedure  for  most infertility treatment  since  the  treatment revolves  around  the wife's ovulation. Daily scans are  done  to visualize  the growing follicle, which looks like a black  bubble on  the  screen.  Most women can see  the  follicle  clearly  for themselves  -  and know by the scans when the egg  has  ruptured. Other  useful information which can be determined by these  scans is  the  thickness of the uterine lining - the  endometrium.  The ripening  follicle produces increasing quantities  of  estrogen, which cause the endometrium to thicken. The doctor can get a good idea  of  how  much estrogen you are producing  (  and  thus  the quality of the egg) based on the thickness and brightness of  the endometrium on the ultrasound scan.

Fig 1. Ultrasound scan showing multiple follicles

Fig 2. Ultrasound scan of the uterus, showing a normal endometrium, which appears as a triple band in the center of the uterus

One of the commonest findings on an ultrasound scan is an ovarian cyst. A cyst is a collection of fluid surrounded by a thin wall ( a fluid-filled sac) that develops in the ovary. Typically, ovarian cysts are functional (not disease-related) and disappear on their own. During ovulation, a follicle may grow , but fail to rupture and release an egg. Instead of being reabsorbed, the fluid within the follicle persists and forms a follicular cyst. The other type of functional cyst is a corpus luteum cyst, which develops when the corpus luteum fills with blood. Functional ovarian cysts usually resolve on their own, and are not to be confused with other pathological conditions involving cystic ovaries, specifically polycystic ovarian disease , endometriotic cysts, or ovarian tumours. Since an ultrasound picture is just a black and white shadow, the doctor has to be skillful in interpreting what the image means. Simple cysts are thin walled, and appear as a large black bubble. Cysts which contain blood ( for example, chocolate cysts found in patients with endometriosis) will have echoes within them, which appear white, and these are described as complex masses on ultrasound. The incidence of follicular cysts is increased in infertile patients taking drugs ( such as clomiphene and HMG) for ovulation induction. Functional ovarian cysts usually disappear within 60 days without treatment. However, if the cyst is larger than 6 cm, or persists for longer than 6 weeks, then further testing may be needed.

Who  does  the scans ? Ultrasound scans can be done either  by  a radiologist;  or  by the gynecologist or  infertility  specialist himself. Remember that the eye only sees what the mind knows, so you must go to a good clinic for your scans. The benefit of having the scans done by the  infertility specialist  himself  is  that he  can  make  immediate  decisions regarding  your  treatment  based on the scan  findings.  If  the radiologist  does  the  scans, then you have to  wait  till  your doctor  has seen the report before knowing what to do next  since the  radiologist  does not make the treatment decisions.  In  any case,  it  is  vital that the ultrasound scans  be  done  in  the Infertility Clinic itself, so that your waiting can be  minimized -  and you don't have to run around from the sonographer  to  the gynecologist.  If  there are any abnormal findings, it  is  vital that  your  gynecologist see the actual  ultrasound  for  himself during  the scan. This provides much more  information  than the printed pictures.

Ultrasound technology has made dramatic advances in recent years, and  now tests have been described which allow the doctor to  use ultrasound  to  assess tubal patency.  Basically,  these  involve passing  a  fluid  into your tubes through the  uterus;  and  the gynecologist  can see the passage of the bubbles into  the  tubes and  out into the abdomen. Since this test (  sonosalpingography) can  be done in the doctor's clinic itself, and does not  involve X-ray  radiation, it has advantages - especially for  documenting that  the tubes are normal. However, the gold standard for  tubal testing remains HSG and laparoscopy today.

Doppler:  The newer ultrasound machines have Doppler  attachments which  allow the doctor to judge the flow of blood in  the  blood vessels.  The  most exciting advance is that of  Colour  Doppler, where the blood flow can be mapped in color on the monitor. While still  a research tool, it may provide important information  for assessing the infertile patient in the coming years.

Three – dimensional ultrasound. Using sophisticated microprocessors, the newest ultrasound machines allow the doctor to reconstruct the image, so that he gets a three dimensional view. While this provides excellent pictures, the true value of this technique for infertility still has to be evaluated.

Ultrasound  now  also offers infertile patients  newer  treatment options  not available before. Modern surgical techniques  have progressively  become  less and less invasive - all  to  the patient's benefit ! From laparotomy to laparoscopy , and  now to ultrasound guided procedures, we are witnessing a change in the  gynecologist's  armamentarium  from  the  knife to the endoscope to the guided needle !

The benefits to the patient are many and include : reduced costs; reduced  hospitalisation  ; reduced risk  of  complications;  and better  preservation  of  fertility,  with  increased  chance  of conception for the future.

Ultrasound-guided procedures can be used to treat a variety of problems seen in the infertile woman.

1.  Egg pickup for IVF - The use of vaginal ultrasound for  egg pickup  has  made egg retrieval a short, simple  and  inexpensive procedure, which can be performed in a day-care unit, under sedation and local anesthesia . The ovaries are normally  present in the pouch of Douglas, and are very accessible  transvaginally. Moreover,  the presence of adhesions does not interfere with  egg collection.

2.  Ovarian  cyst aspiration. An ovarian cyst is  a  very  common condition  in which fluid collects in the ovary.  However,  cysts which are more than 5 cm in size need to be treated, as they  can cause problems ( eg twisting and rupture). Normally, surgery  had to  be  done to remove these cysts - and often this  damaged  the surrounding  normal ovary as well. With  ultrasound-guidance,  we can  stick a needle from the vagina into the cyst, and empty  the contents ( usually clear fluid ) by sucking it out. This  empties the cyst, which often does not recur.

3. Treatment of ectopic pregnancy . With technological advances ( ultrasound  and  beta-HCG  blood tests) the  diagnosis  of  tubal pregnancy can be made very early, usually before rupture. It  can be treated by injecting a toxic chemical, methotrexate, into  the sac,  which  causes the tissue to die and  then  get  reabsorbed, without   any   surgery  whatsoever.  In  more   advanced   tubal pregnancies,  potassium chloride can be injected direct into  the heart of the baby in the ectopic gestational sac, thus killing it and preventing it from growing.

4. Ultrasound-guided tubal embryo and gamete transfer for IVF and GIFT  techniques. Techniques have been devised to pass a  special tube  -  the Jansen-Anderson catheter set -  into  the  fallopian tubes  through  the vagina under ultrasound guidance,  so  as  to place  the  embryos and /or the gametes in the  fallopian  tube. Since  the tube offers a better environment for the  gametes  and embryos  than the uterine cavity, it is believed that  this  will improve pregnancy rates.

5.  Tubal  recanalisation  for cornual blocks  (  proximal  tubal obstruction)  . Often cornual blocks are due to the  presence  of mucus  plugs and amorphous debris in the tubal lumen.  Ultrasound guided  tubal catheterization can effectively treat  the  blocked tubes in some of these patients.

The   scope  of  ultrasound  guided  procedures   has   increased dramatically in the last few years; and with further improvements in technology, we can expect this list to become even longer, and doctors become more versatile with using this technology.