Uterine septum is the most common congenital anomaly of the uterus and it might in some circumstances increase the risk of pregnancy loss. Many patients are unaware of this condition until they enter childbearing age. The uterine septum might go completely unnoticed until it begins to affect pregnancy.
The human uterus consists of a cavity that is surrounded by muscle and vasculature. In some other animals, for example in a mouse, the uterus consists of two completely separated tubular structures. Each of them can carry multiple embryos. The human uterus was also formed from two separate tubes that are supposed to fuse together before birth. However, some females are born with a uterus that has not completely fused together.
The "uterine septum" is the physical barrier keeping the incompletely fused uterus separate in two parts. This separation typically persists in the upper part of the uterus and extends down towards the vagina. A complete septum fully separates the uterus in two cavities. It can even continue and separate the cervix and vagina in two separate tubes. This is fairly rare and most of the patients present with a "partial uterine septum". That means that the uterine cavity is only partially separated, almost always at the top. In case of the partial uterine septum, we can measure how far the separation extends from the top of the uterus. The partial uterine septum is often referred to as "the septum" and is actually only a relatively small indentation at the top of the uterus. However, since the embryos attach at the top of the uterus, they can affect implantation and cause recurrent pregnancy loss (RPL)
It is very unlikely that this condition will be picked up anytime prior to visiting a fertility specialist. Most of the patients will not have any symptoms or any other problems associated with the uterine septum except when trying to become pregnant. Most of the patients do not have any reason to have a transvaginal ultrasounds performed. Among the patients who for some reason need to have a transvaginal ultrasound, very few actually get diagnosed with a uterine septum. The reason is that the shape and form of the uterus might not be clearly appreciated during a routine scan. It is very easy to miss it on a 2-D ultrasound.
Most of the uterine septi are diagnosed by fertility subspecialists, after the patient presents with recurrent pregnancy loss. Some clinics report that 20 to 30% of their patients have more or less evidence of a septate uterus. A skilled ultrasonographer can diagnose the septum on a regular two dimensional (2-D) ultrasound by sweeping the probe from side to side, however a 3-dimensional (3-D) ultrasound can give an unmatched view of the uterine shape.
It is important that your fertility specialists makes the correct diagnosis of the uterine septum versus a bicornuate uters. The uterine septum contains a separation in the uterine cavity, however the outer appearance of the uterus is normal. A bicornuate uterus at the other hand has a completely separated upper end both internally and externally. Diagnosing this properly is very important since an attempted resection of the bicornuate uterus, that is improperly diagnosed as a uterine septum might create a uterine perforation. Therefore the 3-D ultrasound or an MRI is strongly advised prior to any corrective surgery. The old-fashioned way of diagnosing the uterine septum by a hysterosalpingogram (HSG) only yields information about the cavity but not about the outer shape of the uterus. Therefore it is very important for the patient to have the proper imaging in place prior to making any decisions.
At the Tree of Life Center, we use a 3D vaginal ultrasound to determine the extent of the uterine anomaly and create a 3D picture of the uterine cavity. Our software allows us to rotate the virtual image of the uterus in any dimension and clarify all issues. The 3D ultrasound allows for three dimensional reconstruction of the uterine cavity with visualization that is superior to an HSG and can clearly identify the uterine septum. While a good sonographer might recognize a septum on 2D ultrasound, a detailed visualization and image post-processing can only work with a 3D ultrasound device. In comparison, the HSG fills out the cavity with contrast and utilizes low dose radiation. We see a lot of images taken in the wrong plane and the uterine shape can not be clearly seen on some studies. The HSG can not really adjust the plane and it mainly depends how your uterus lies in the abdomen. The 3D sonography can rotate the image using computer post-processing of the ultrasound data into the desired plane. Therefore, regardless how your uterus is positioned during the ultrasound acquisition, the correct plane can be adjusted. In addition to finding the right plane, the ultrasound will visualize the myometrium (the muscular layer that surrounds the cavity). This again allows to see the uterine cavity and the entire uterus around it! The 3D sonography is therefore only comparable to a uterine MRI. However the MRI is very expensive and patients need to inject Gadolinium as a contrast medium and stay in the tube for a prolonged period of time. Some patients need to abort the MRI due to not tolerating the confined space or the IV contrast medium.
We have included an image above of a patient who was diagnosed with a uterine septum at our Tree of Life Center Los Angeles fertility clinic. We went ahead and did a surgical resection of the uterine septum and the picture after surgery is included below. A tiny residual where the septum was can still be seen, but the large indentation and Y-form cavity has been surgically corrected.
Surgical management in the form of a hystoroscopic removal are always recommended before attempting to get pregnant in cases of a very long and prominent uterine septum. In cases where the septum is very small and affects only the very top of the uterus, there might not be any need to perform surgery. The clinical history plays a very important role, since some patients can be affected by even a relatively small uterine septum.
The explanation of the detrimental effects is that the uterine septum lacks adequate blood supply and the embryo has a high risk of failure if it attempts to develop on the septum itself. Some very large uterine septi can affect the pregnancy at later stages and the baby may not be able to position itself before the birth with the head down.
At the tree of life Center we can offer an online consultation and review the prior studies and provide you with a second opinion about your uterine septum. We also welcome to visit our clinic in Los Angeles and have a 3-D ultrasound performed to further evaluate your anomaly.
In the case that your uterine septum requires treatment, we will be happy to provide you with a complete package that includes a hysteroscopic resection in one of our surgery centers. This procedure can be completed in one day without any incisions. Special care needs to be taken to avoid going too far with the uterine septum resection and to avoid creating a hole at the top of the uterus. In some cases we utilize in ultrasound during surgery or perform a concomitant laparoscopy to evaluate the uterus after introducing a small camera through the belly button.
Please feel free to contact us if you have any questions!