Conjoined Twins Definition, Reason, Symptoms, Treatment & Prevention
Understanding
Conjoined twins are a condition in which two babies are born physically united with each other. Conjoined twins can occur when an embryo at an early stage of development undergoes partial separation to form two individuals. Even though two fetuses will develop from the embryo, some of the limbs of the two fetuses will remain fused. This fused condition often occurs in the chest, abdomen, or pelvis. Conjoined twins can also share one or more organs in the body.
Some conjoined twins do not survive and may die in the womb or shortly after birth. Some conjoined twins who survive can be separated surgically. However, the success rate of the surgical process also depends on various factors. This includes where the conjoined twins’ body parts are fused, the number and type of organs that are divided, as well as various other factors that are quite complex.
Symptom
There are no specific signs or symptoms that can indicate the occurrence of a condition of pregnancy with conjoined twins. However, like other twin pregnancies, the uterus can enlarge more quickly than in a single fetus. Complaints of nausea, vomiting, and feeling tired in early pregnancy can also feel more severe. Conjoined twins can be diagnosed during routine pregnancy control through ultrasound examination (USG).
Conjoined twins are generally classified based on fused body parts, which can occur in more than one location. Sometimes, the two fetuses also share certain organs or body parts. The specific anatomy of each pair of conjoined twins can vary. Conjoined twins may join at the chest, abdomen, spine, pelvis, or head.
Reason
There are several theories regarding the occurrence of conjoined twins. Initially, identical twins (monozygotic twins) can occur when one egg that has been fertilized by a sperm cell divides and develops into two fetuses. Eight to 12 days after conception, the layers of the embryo that will divide to form monozygotic twins begin to develop into specific organs and structures.
It is believed that if the process of dividing the embryo goes slower than this period, generally on days 13 to 15 after conception, division can stop before the process is complete. As a result, the two fetuses that were meant to be formed from the beginning were not completely separated, but partly still fused.
An alternative theory posits that two separate embryos may fuse at an early stage of development. However, the causes of each of these scenarios are not known with certainty.
Diagnosis
Conjoined twins can be diagnosed using ultrasound examination from the end of the first trimester of pregnancy. A more detailed ultrasound examination and echocardiography can be used in mid-pregnancy to determine the degree of union of the two fetuses and the functionality of the organs in each fetus.
If ultrasound detects conjoined twins, a magnetic resonance imaging (MRI) examination can also be done if deemed necessary. An MRI will produce more detailed images of the parts of the body that are joined together and the organs that are divided.
Treatment
Treatment for conjoined twins depends on a variety of factors, including the health status of both individuals, body parts that are fused together, and the presence of divided vital organs or structures.
During pregnancy, women carrying conjoined twins need careful monitoring. Delivery is generally performed by planned cesarean section method.
After the conjoined twins are born, a complete evaluation will be carried out by the team of health workers involved to make various decisions regarding treatment. The potential for surgery that can be performed and the right time to separate the two individuals will also be evaluated.
There are quite a number of complex factors that need to be considered when deciding whether to operate to separate the two babies. Such surgical procedures can be planned according to various factors.
The team of doctors will observe the divided vital organs, the ability of each baby to go through surgery based on their health status, the possibility of the smooth running of the operation, the possibility of reconstructive surgery needed by each baby after a successful separation, the functional support needed by each baby, and the obstacles that will be experienced by the baby if surgery is not performed.
Prevention
Because the cause of conjoined twins in pregnancy is not known with certainty, there is no method of prevention that is known to be fully effective in preventing this condition.