Premature birth, or birth that happens too early, before 37 weeks of pregnancy, can lead to longer hospital stays for newborns, and can contribute to an increase in health problems over babies who are born at full term. Since it’s not always entirely clear why premature birth happens, it isn’t always something healthcare providers can work to prevent, but there are a few conditions which can make premature birth much more likely, and a few medications that can cut down on the risk if they are prescribed during pregnancy.
Three of the biggest indicators that a pregnant person may be at risk for a premature delivery are a previous premature birth, a short cervix, and a pregnancy carrying twins or multiples. If you have a short cervix, the hormone progesterone may be an important part of the line of defense.
Some research suggested that progesterone treatment was helpful for those with a history of prior preterm birth, and that getting weekly progesterone injections would lower the risk of preterm labor. However, the PROLONG study published in 2020 found that weekly progesterone injections did not have a significant benefit for those with a history of preterm birth. Because the evidence is mixed, if you have a history of preterm birth, talk through the possible benefits and risks of progesterone treatment with your healthcare provider.
Progesterone is not recommended if you’re having twins or multiples and are at risk for preterm birth.
Talking to your doctor about progesterone and short cervix
Screening for a short cervix isn’t yet a routine part of prenatal care in all hospitals and regions, but it’s becoming more and more common. Women who have short cervixes during pregnancy have about a 50% likelihood of delivering preterm. If you’re pregnant with just one baby, and your healthcare provider isn’t talking about screening for a short cervix, you can open up a discussion about the possibility some time around the middle of the second trimester. Many healthcare providers screen for short cervix during the middle of the second trimester.
If you’re diagnosed with a short cervix, your healthcare provider may prescribe progesterone to be delivered vaginally. This may be in the form of a gel, a suppository, or a capsule. Vaginal progesterone may be prescribed to be taken once or twice a day. Women who are prescribed vaginal progesterone can begin at or before 24 weeks of pregnancy, and continue to take progesterone until just before their due dates.
If you’re prescribed vaginal progesterone, it’s important to talk to your doctor if you have a history of:
- High blood pressure, heart disease, or congestive heart failure
- Chronic conditions like migraines or asthma
- Kidney disease
- Seizures or epilepsy
- A history of depression
- Risk of coronary artery disease
A short cervix can be an unexpected worry, since there’s no way to screen for it before pregnancy. Progesterone can’t prevent preterm delivery every time, but it can certainly decrease the risk.
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