Why Does a Miscarriage Occur?

    A miscarriage, also referred to as a spontaneous abortion, occurs in many pregnancies. Typically, a miscarriage happens before the end of the first trimester, but it can happen at any time in the pregnancy up to 20 weeks. After 20 weeks, the loss of pregnancy is considered a preterm birth.

    Studies show that up to 50% of pregnancies end in miscarriage before the mother realizes she was pregnant. Between 10-25% of all clinically recognized pregnancies will end in miscarriage, and most miscarriages occur before the 7th and 12th weeks of pregnancy. 

    Genetic History, Health and Pregnant Miscarriage
    In some cases, women are genetically predisposed to pregnant miscarriage. Women who have multiple miscarriages in pregnancy may fall into this category. The root cause of the pregnant miscarriage may remain unknown or a health related issued may be revealed.

    Lower than average HCG or progesterone levels may cause pregnant miscarriage. Progesterone is released by the corpus luteum during ovulation to thicken the uterine wall and prepare the uterus for implantation of the fertilized egg. If the egg is not fertilized, the corpus luteum dies off after 14 days and the elevated progesterone levels return to normal. The menstrual cycle follows shortly after. If a fertilized egg is implanted in the uterus, HCG is released. The HCG keeps the corpus luteum alive and progesterone levels stay high throughout pregnancy.

    If there is a health condition that limits HCG or progesterone released, the pregnancy will likely end in a pregnant miscarriage and progesterone and HCG are both needed to carry a pregnancy to term. Even with genetic and health issues, there are times when pregnant miscarriage occurs with no known cause.

    Can I Get Pregnant Again After Pregnant Miscarriage?
    Yes, many women can conceive after a pregnant miscarriage. About 95% of women who have one pregnant miscarriage will conceive again and give birth. Even women who have more than one pregnant miscarriage have a 75% chance of achieving a full-term pregnancy. In some cases, increasing viability of full-term gestation may require medications to boost HCG or progesterone, but this is not always the case.

    Women are most fertile in the time immediately following a pregnant miscarriage, but most obstetricians and gynecologists will suggest waiting until the first normal menstrual cycle has passed before trying to conceive again. In some cases, doctors suggest waiting six months or more before trying to conceive, but this depends on the reasons for the pregnant miscarriage and the common practices of the attending physician.

    Pregnant miscarriage is more common than many women understand. Just because a pregnant miscarriage occurs, women are not necessarily less likely to conceive and achieve motherhood. It is best to work with the attending gynecologist or obstetrician to maximize the chance of carrying the fetus to term after a pregnant miscarriage.