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Decreased fetal movement can be caused by a number of different factors, some more serious than others. Many pregnant women notice that their babies are more active at certain times of the day, for instance, particularly in the third trimester as the fetus begins adapting to a more regular sleep-wake cycle. The mother’s nutrition, hydration, and stress level can also play a part. It is sometimes the case that decreased movement is a sign of something much more serious, however, like a rupture in the amniotic sac or a problem with the baby’s oxygen. Most medical experts recommend that pregnant women keep track of the movements they feel in order to quickly notice when something might be wrong.
Even in utero, babies spend part of each day and night asleep. It is sometimes the case that a decrease in movement simply indicates that the fetus is resting. Many women notice that the more active they are, the quieter the fetus gets, possibly because the mother’s movement provides a comforting rocking motion that can encourage the baby to rest. In most cases these naps are brief, often no more than an hour. As long as the baby starts moving vigorously again after a period of time, there is not usually any cause for alarm.
Maternal Stress or Nutritional Problems
Fetuses tend to be very responsive to their mothers’ emotional and physical state, both of which can sometimes play a part in activity and movement. When a pregnant woman is very stressed, for instance, the baby may respond by moving less or lying still. The same is often true in women who are dehydrated or who have skipped meals. Medical experts stress that nutrition is really important during pregnancy for both the mother and baby’s sake. In most cases, drinking some water, having a snack, and lying down for a bit will encourage the fetus to start kicking again.
Premature Rupture of Membranes
Decreased fetal movement is sometimes caused by a leak or rupture in the amniotic sac that surrounds the baby. People often refer to this phenomenon as a woman’s water breaking. Membrane rupture is a normal part of a full-term delivery, but when the fluids leak before a woman’s due date it is often a sign of trouble. The amniotic fluid is what keeps the developing fetus stable, warm, and protected. Leaks can lead to stress and problems with nutrition and oxygen, and also make infection more likely. All of these can lead to slowed or stopped movement.
Another possibility is placental abruption, a potentially serious condition in which the placenta, the organ that feeds and nourishes the fetus, separates from the uterine wall. In some cases the abruption is relatively minor and will heal on its own, but in more severe cases the separated organ can actually restrict the flow of oxygen and blood to the baby, which can lead to death if not promptly treated. Surgery can sometimes repair the damage or, if the pregnancy is far enough along, labor can be induced or the baby can be delivered by cesarean section.
Healthcare experts aren’t always able to pinpoint exactly what causes the placenta to separate, but poor fetal development, severe infection, or other abnormalities can trigger the condition. Accident and injury can also bring it on. Women who are at risk are usually monitored closely and advised to avoid strenuous activity and high-stress situations.
When the umbilical cord fails to deliver enough oxygenated blood to the baby, medical experts sometimes diagnose fetal hypoxia, a potentially fatal condition that can have long-term effects on the brain and overall development. This happens with the cord gets kinked or twisted, but can also result if the cord is poorly formed. Babies who experience a sudden dip in oxygen usually slow or stop their movements to conserve energy.
Fetal hypoxia is difficult to diagnose before it’s too late. When doctors realize what’s going on they can often repair or readjust the umbilical cord, often through surgery, or can take other steps to mitigate damage. Some babies born after experiencing limited oxygen in the womb suffer from neurological conditions, such as epilepsy or cerebral palsy, while others are born with abnormalities of the heart, lungs, or other organs. Experts also believe that the risk of sudden infant death syndrome (SIDS) may be increased when a baby has suffered from fetal hypoxia.
In rare cases a sudden decrease in fetal movements can be a sign that the baby has died, a condition referred to medically as “fetal demise.” There isn’t always a clear explanation for why this happens. Healthcare providers are sometimes able to identify a cause, like infection or trauma, but not always. Babies who have died in utero must usually be delivered as if they were alive, though a lot of this depends on how big they are.
Importance of Tracking Movements
Medical professionals often advise pregnant women to take note of their baby’s movements throughout their pregnancies. Writing down or otherwise tracking the time of day, frequency, and intensity of kicks and jabs can help women notice when a decrease is just a normal lull versus when it is something to be concerned about. Most people say that their babies fluctuate between being very active and almost still, and knowing what is normal is often very comforting.
When Mothers Should Get Help
Different doctors have different standards, but in general any woman who is concerned about a lack of fetal movement should seek prompt care. Instincts are an important part of pregnancy, and some mothers say they simply knew