Undetected Loss of Pregnancy
Sometimes during a pregnancy, the baby stops growing and the pregnancy has, for all intense purposes, ended, though the woman has no signs or symptoms of miscarriage, such as cramps or bleeding. This type of miscarriage is called a "missed miscarriage." A woman who has a missed miscarriage will remain unaware that anything has gone amiss with her pregnancy until such time as a routine checkup shows clinical evidence that the pregnancy is no longer viable.
Clinical findings which suggest missed miscarriage include two successive hCG blood tests which show that hCG blood levels are in decline and/or an ultrasound test which reveals the baby's heart is no longer beating. Often, the first sign of a missed miscarriage comes during routine fetal heart rate monitoring when the doctor fails to detect an audible heartbeat by the 12th week of pregnancy.
Once the condition is diagnosed there are decisions to make. Sometimes a spontaneous natural miscarriage, or a miscarriage which occurs without medical intervention, will take place days or weeks after diagnosis. Some women may prefer to wait and see what happens, in hopes of avoiding a surgical procedure, while other women find the waiting an emotional ordeal and so opt to have a D & C in order to bring about a quick end to sad situation.
There is a type of missed miscarriage which goes under a special heading termed "blighted ovum." In this condition, the sac in which the fetus is situated, along with the fetus' placenta continue to grow, while the baby's development is arrested. Sometimes the woman continues to experience the symptoms of pregnancy, however, there is never an audible heartbeat during routine fetal heart rate monitoring and ultrasound testing reveals that the gestational sac is empty.
The usual cause of a missed miscarriage is much the same as in any other miscarriage occurring during the first trimester of pregnancy: chromosomal abnormalities of the fetus. While this may seem like small comfort, a miscarriage is nature's way of preventing a tragedy in the form of a baby born with birth defects. Most of the time, a woman has an excellent chance of having a normal, healthy pregnancy in the future, if she so chooses. Sometimes miscarriages become recurrent in which case you should consult your doctor about testing for specific conditions other than chromosomal abnormalities which might cause recurrent miscarriages.