Heterotopic pregnancy is the presence of two concurrent pregnancies with separate implantation destinations. One of these is a suitable intrauterine pregnancy but the other becomes non-viable as it is an ectopic pregnancy. Ectopic pregnancy occurs beyond the uterus, most probably in the fallopian tube.
This kind of pregnancy is as dangerous as ectopic pregnancy. On the other hand, it is made difficult by the fact that most parents wish to keep the viable pregnancy while having to terminate the other.
Heterotopic pregnancy percentage
Like all multiple pregnancies, heterotopic pregnancy is a rare condition in couples who are trying to conceive with assisted reproductive producers like in vitro fertilization (IVF).
As many as 1 in 1000 assisted pregnancies will get this condition. While this pregnancy is a common case in women to have a natural conception, some estimates suggest that the rate of heterotopic pregnancy is still significant ranging from 1 in 7000 to 30000 pregnancies.
It is probably defined as the presence of multiple gestations, with one being present in the uterine cavity and the other will present outside of the uterus like fallopian tube and uncommonly in cervix or ovary.
A woman will have a heterotopic pregnancy may or may not have the symptoms. This is especially because half of these pregnancies are only diagnosed when the fallopian tube is ruptured.
If symptoms present means, it will show:
- Abnormal vaginal bleeding
- Mild to severe abdominal discomfort or cramping
- Pain in the side of abdomen
If you are having severe pain, heavy bleeding, feeling faint or having any other worrisome symptoms, go to the emergency room as a ruptured tube can be deadly if untreated.
Causes of heterotopic pregnancy
Heterotopic pregnancy is a rare condition that is characterized by the presence of simultaneous intra or extra uterine pregnancy.
- Assisted reproductive techniques (ART)
- Infertility treatment such as IVF / ICSI / IUI
- Past history of pelvic inflammatory disease (PID)
Diagnosis of heterotopic pregnancy:
Very simply, it is difficult for doctors to diagnose heterotopic pregnancy in its early stages. Women may have vaginal bleeding and cramping, but these are symptoms that can be present in a normal pregnancy. At the same period of time it is easy to miss a heterotopic pregnancy during a routine ultrasound since the technician may only check the developing fetus in the uterus and they will miss the pregnancy beyond that. Suspicion of a heterotopic pregnancy will require four to five weeks till confirmation by ultrasound.
Until then the pregnant woman will require surveillance and vigilant monitoring. She will require repeated blood tests along with USG to reach a definitive diagnosis.
Risk factors of heterotopic pregnancy which may include:
- Tubal damage
- Pelvic inflammatory disease
- Tubal infertility
- Tubal reconstructive surgery
- Uterus malformation
- Family history
- Previous case of ectopic pregnancy
What is the risk of a heterotopic pregnancy?
In the natural conception cycle heterotopic pregnancy is a rare event occurring less than 1 or 2 cases in 30000 pregnancies.
In in vitro fertilization it will occur 1 in 500 cases.
Are the heterotopic pregnancy twins?
Heterotopic pregnancy is diagnosed as the simultaneous presence of fetuses at two or more implantation sites. This heterotopic pregnancy incidence is very rare with the presence of live intrauterine twins being even rarer. Diagnosis in such cases is difficult with ultrasound to find out and do it clearly. Management of this will be primarily surgical.
Can a baby survive in heterotopic pregnancy?
Any fetus located outside of the uterus will not survive, and its presence could cause potentially life threatening bleeding in the mother if a tissue spontaneously ruptures. As a result, this type of pregnancy will require termination.
What is a pseudo gestational sac?
A pseudo gestational sac is a false cavity or intra cavity fluid. It is the accumulation of small amount of intrauterine fluid inside the womb. In the setting of a positive pregnancy test and abdominal pain this can confuse with an true pregnancy.
Most ectopic pregnancies involve an embryo setting in a fallopian tube, but it can also happen in the ovary or the abdominal cavity. An ectopic pregnancy can be fatal for a pregnant person without prompt intervention. Subsequently, the fallopian tube with an ectopic pregnancy may burst leading to severe bleeding in the woman.
A tubal pregnancy is the most common type of ectopic pregnancy. It happens because the fertilized can not travel back to the uterus. Most often it is due to a damaged fallopian tube. Hormonal imbalances or development of the fertilized egg also might play a role.
Any fetus developing outside the uterus cannot survive and stops growing after some time. In addition, its presence could cause potentially life threatening bleeding in the mother if this ruptures spontaneously. As a result, your doctor will suggest termination of this pregnancy.
The good news is that it is often possible to do without terminating the healthy intrauterine pregnancy. In addition, this process typically involves surgery which may or may not require the removal of the affected fallopian tube.
While heterotopic pregnancies carry an risk of miscarriage, around 67% of women are able to carry the intrauterine baby to term. However, if you have experienced loss of a fetus due to heterotopic pregnancy, it is perfectly normal as these pregnancies impart increased risk.
Shortly the treatment of heterotopic interstitial pregnancy aims to preserve the intrauterine pregnancy. At the same time, removing or interrupting the evolution of the ectopic pregnancy can be done using a minimally invasive method. The therapeutic methods include surgical, medical or watchful expectancy.