what causes a molar pregnancy?

Molar Pregnancy Causes

A molar pregnancy is a rare complication arising as a result of chromosomal imbalance at the time of fertilization. There are two types of molar pregnancy – partial and complete, both occurring at conception itself. A complete molar pregnancy occurs when the mother’s ovum is empty and does not contribute any chromosomes at conception for the formation of a baby. Hence, no embryo is formed and there is no amniotic sac as well. Only an abnormal placenta starts growing in the uterus. These cells grow in clusters and bear a resemblance to a bunch of grapes. In a partial molar pregnancy, the mother contributes the normal 23 chromosomes but, the father contributes 46 chromosomes. This is usually a result of two sperm fertilizing a single ovum or egg. Instead of splitting into twins, a single abnormal embryo begins to develop along with abnormal placental tissue. Due to the genetic malformation, the embryo can never develop into a healthy, normal baby. With the passage of time, the abnormal placental cells grow rapidly and cannot provide nourishment to the developing embryo. Hence, under no circumstance can the pregnancy be successful. Hence, we see that a molar pregnancy is purely genetic and has nothing to do with diet or lifestyle. However, maternal age, geographical location and previous molar pregnancies can influence the occurrence of a molar pregnancy.   

The main symptom of a molar pregnancy is a larger than normal uterus as the abnormal cells multiply quickly. High hCG hormone levels are also linked with molar pregnancies as the abnormal placenta keeps producing the hormone. High hCG levels also cause severe nausea and vomiting. Bleeding is another symptom of a molar pregnancy and occurs around the 12th week in most cases. Sometimes, abdominal pain or discomfort is also experienced. Hypertension and preeclampsia are other symptoms of molar pregnancies. A complete molar pregnancy is usually diagnosed around the 12th week of gestation as no fetal heartbeat is heard.   

A molar pregnancy can be confirmed only through an ultrasound as this is the lone method through which the actual status of a pregnancy can be known. On confirmation, the uterus is immediately cleaned and the cells are removed carefully via a D&C or D&E. If ignored, a molar pregnancy can develop into a form of cancer. Hence, careful monitoring for recurrent cell growth is imperative. Seeking a doctor’s advice with regard to conceiving again is highly recommended so as to prevent further complications.

Submitted by P T on July 22, 2010 at 12:40

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