Most pregnant women are very healthy during pregnancy and have no problems, but a certain number of women will wind up doing some form of bed rest for a variety of problems. Some of these problems include:
Incompetent cervix: Cervix opens too early and would allow premature birth. Sometimes this is treated with surgery to close the cervix until the pregnancy reaches a safe age for birth to occur.
High Blood Pressure (PIH): When a mother's blood pressure goes too high it can cause problems for her and the baby. Rest can help reduce these readings in blood pressure.
Threatened Miscarriage: If the pregnancy is in question or if there is bleeding bed rest may be ordered.
Premature Labor: Sometimes the stress of life in combination with the physical stress of pregnancy or for reasons unknown creates a situation where the pregnancy is threatening to end early. Bed rest is one of the tools used to help prevent preterm birth.
The benefits of bed rest vary from mother to mother and for the reason that they are using this tool. Most doctors and midwives say that the added rest and relaxation are alone beneficial. But there are also physical benefits of bed rest for some moms, including lowered blood pressure, less pressure on the cervix, and better blood flow to the baby.
Types of bed rest:
Modified Bed rest: This type will take whatever form your practitioner advises. For some women this is being allowed to work at a desk but in bed while at home, for others it's strict rest hours a couple of times a day.
Strict Bed rest: This form usually means you're allowed in bed or on the couch and only up to use the bathroom. There may be requirements made on how many times a day you can change locations.
Hospital/Complete Bed rest: This form is the strictest and may include hospitalization. You will use a bedpan during this form and not be allowed up during the day. Sometimes it also involves special positioning like your head lower than your body (Trendelenburg) to alleviate pressure on the cervix.
While bed rest seems to have many advantages there are also no studies that prove its effectiveness for every pregnancy complication. Wise use of this sometimes physically debilitating and mentally/emotionally draining experience are highly recommended.