Bleeding from the Vagina in Pregnancy Anatomy
To better understand threatened miscarriage, it helps to understand the anatomy of the uterus, cervix, and Fallopian tubes.
Anatomy of the female reproductive tract includes:
- The uterus, cervix, and vaginal canal
- The fallopian tubes: these paired structures connect each ovary to the uterus.
- The ovaries: one on each side of the uterus. The normal ovary is approximately the size of an unshelled almond.
The fetus grows within the amniotic within the uterus:
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- Weiss JL, Malone FD, Vidaver J, et al. Threatened abortion: A risk factor for poor pregnancy outcome, a population-based screening study. Am J Obstet Gynecol. 2004 Mar;190(3):745-50. 
- Yip SK, Sahota D, Cheung LP, Lam P, Haines CJ, Chung TK. Accuracy of clinical diagnostic methods of threatened abortion. Gynecol Obstet Invest. 2003;56(1):38-42.