Ovarian Cyst found during Pregnancy
Every pregnant woman should have an ovarian cyst. This cyst is the corpus luteum, the “cyst of pregnancy,” which produces the hormone Progesterone. All pregnancies are dependent upon progesterone for the first 10-12 weeks of gestation. When the corpus luteum is surgically removed before 11 weeks gestation, most pregnancies will end in miscarriage. Miscarriage can be prevented with progesterone supplementation until 12 weeks gestation.
Most corpus luteum measure less than 5 cm. Sometimes we discover ovarian cysts which are larger than 5 cm, and which persist past 12 weeks. Ovarian cysts in pregnancy can be categorized as follows:
- Size: less than 5 cm, 5-10 cm, greater than 10 cm.
- simple: like a water filled balloon
- complex: like a water filled balloon filled with other water filled balloons or dividing lines
- complex with solid components: like a complex cyst, but ALSO with thicker dividing lines, some “filled in” balloons, and some “bumps” on the walls
- Gestational Age:
- first trimester (less than 13 weeks)
- second trimester, before viability (13 to 22 weeks); second trimester, peri viable (22-26 weeks)
- third trimester (26 weeks and beyond)
- Asymptomatic, no pain, the pregnant mother does not know the cyst is there
- Symptomatic, with pain. Early pregnancy is marked by many different feelings and sensations, so sometimes it may not be clear that a woman’s pain is actually coming from the ovarian cyst
The need to worry, or the medical indication to intervene (to remove the cyst with surgery) is based on the combination of size, description, gestational age and symptoms. One end of the spectrum is the Absolute Need to remove a 12 cm cyst that is clearly causing pain at 15 weeks of pregnancy. The other end of the spectrum is warning Against removing a 4 cm simple cyst that is not causing any pain. Most patients have something in between.
Which Cysts to Follow
Ovarian cysts can lead to a number of potential problems. In pregnancy the problems are more acute in the asymptomatic phase because the risk of premature delivery caused by (or associated with) surgical intervention Increases with gestational age after approximately 20 weeks. Also, the window for laparoscopic surgical management of ovarian cysts closes as the pregnancy continues past 20 weeks.
The Potential Problems
- Pain: We can’t predict which cysts will cause, or continue to cause pain. Cysts can cause the ovary to twist on its blood vessels. Torsion (twisting) REALLY HURTS and can damage the ovary; it can only be treated with surgery. A cyst size over 5 cm can be, but is not always, associated with pain.
- Rupture: ALMOST NEVER HAPPENS.
- Cancer: during pregnancy this is a rare but serious finding.
- Size and Surgery: as the cyst gets bigger, assuming it is not cancer, it becomes harder to remove the cyst without removing the entire ovary. It is really important to avoid taking out ovaries in women considering pregnancy in their future.