Signs & Symptoms of Low Progesterone During the First Trimester

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Progesterone is integral to a healthy pregnancy. According to the website Test Country, a health and drug information center, progesterone increases the chance of pregnancy by increasing a woman’s body temperature and increasing vaginal mucus. Both facilitate sperm’s journey to the egg. When a woman becomes pregnant, progesterone maintains the uterine wall for implantation of the embryo and prevents contractions, which can cause miscarriage. In the first trimester, the ovaries produce progesterone; the placenta takes over around week eight or nine.

Breast Tenderness

The Labor of Love, a website dedicated to pregnancy and parenting, says that breast tenderness is normal during late pregnancy, but it might be a sign of low progesterone in the first trimester, especially if it is constant.


Test Country suggests that if you crave sleep, but do not bounce back after a nap or a good night’s rest, you may be suffering from low progesterone levels. The Labor of Love points out that while pregnant women are often tired, if fatigue is unrelenting, you should talk to your doctor.

Low Blood Sugar

Low progesterone levels can cause low blood sugar, according to The Labor of Love. Symptoms of low blood sugar include feeling light-headed or clammy and sweaty. You can eat more to regulate your blood sugar, but this won’t address the underlying problem if low progesterone is to blame.

Vaginal Dryness

Since progesterone spurs the production of vaginal mucus, you will feel uncomfortable and dry without it, notes The Labor of Love. If you suddenly notice a difference, consult your doctor. Your progesterone level may have dropped.


Spotting can be a normal part of pregnancy, but should always be reported to your doctor immediately, especially if it is heavy, The Labor of Love cautions. It can be caused by problems other than low progesterone and can be a warning of miscarriage, although low progesterone is one cause.

Other Symptoms

Low progesterone can also cause psychological and cognitive problems. Although mood swings are common in pregnancy as all hormone levels fluctuate, consult your doctor if you’re having trouble remembering things or if you feel unaccountably depressed, especially in the first trimester. Some women may experience panic attacks. The Test Country website also cites an unexplained increase in weight as a symptom, although this, too, is a common development in pregnancy.