The risk of ectopic pregnancy is almost nil beyond the 12th week of pregnancy, while the risk of miscarriage really dramatically drops by this stage.
Late Miscarriage -- Between the third month and 20th week of pregnancy, a spontaneous abortion is known as a late miscarriage. The symptoms are similar to the first trimester miscarriage. In many cases, an incompetent cervix is responsible. This is when the cervix dilates prematurely and cannot carry the fetus. This is also known as a weak cervix. Trauma to the cervix as a result of infection, for example, can trigger premature dilation.
If an incompetent cervix is caught early enough, the cervix can be stitched up and the pregnancy can be saved. Around 38 weeks prior to labor, the stitches can be removed and a normal vaginal birth can take place.
If the miscarriage is inevitable and can't be prevented, a D & C can be performed up until the 20th week. A miscarriage after 20 weeks is no longer a miscarriage but now called a premature birth, or worse -- stillbirth.
The symptoms of premature labor are: contractions accompanied by vaginal bleeding, vaginal discharge, lower back pain, and vaginal pressure anywhere from the 20th week to the 37th week. Premature rupture of the membranes (the amniotic sac) occurs in 20-35% of all premature deliveries.
What causes premature labor?
The causes of premature labor at this stage are not known, but there are some factors that can trigger it:
•Sexually transmitted diseases
•Medication not prescribed by your doctor
If your doctor is successful in stopping the contractions with medication, you may be put on strict bed rest for the duration of your pregnancy. On the other hand, if your membranes have ruptured or you any have any vaginal bleeding, there is little chance you can stop the labor; you will need to go ahead and deliver.
Some tables indicating the risk of miscarriage for various groups are presented below.
|20-29 years old||12% risk of miscarriage|
|45 or older||52% risk of miscarriage|
|Miscarriage before 12 weeks||4 in 5|
|Miscarrying after 12 weeks of pregnancy||1 in 30|
|Miscarriage with abnormal chromosomes||1 in 2|
|When previous miscarriage had abnormal chromosomes||1 in 1.25|
|General Risk||1 in 66 pregnancies|
|With PID||1 in 9 pregnancies|
|Over age 34||1 in 27 pregnancies|
|Previous ectopic||1 in 6 pregnancies|