Pregnancy which continues following threatened aboion is likely to have increased incidence of?
**Core Concept**
The question is testing the understanding of the relationship between threatened abortion and the subsequent pregnancy outcomes. Threatened abortion, also known as threatened miscarriage, is a condition where there is vaginal bleeding during the first 20 weeks of pregnancy, but the cervix remains closed. This condition is often associated with an increased risk of preterm labor, fetal growth restriction, and other complications.
**Why the Correct Answer is Right**
The correct answer is related to the underlying pathophysiology of threatened abortion. Threatened abortion is often caused by hormonal imbalance, specifically an imbalance of progesterone and estrogen. Progesterone is essential for maintaining the pregnancy, and any decrease in its levels can lead to bleeding and increased risk of miscarriage. Women who experience threatened abortion may have underlying conditions such as luteal phase defect, which can lead to an increased risk of preterm labor and other complications.
**Why Each Wrong Option is Incorrect**
* **Option A:** Placenta previa is a condition where the placenta partially or completely covers the cervix, leading to vaginal bleeding. While it is a possible complication of pregnancy, it is not directly related to threatened abortion.
* **Option B:** Gestational diabetes is a condition that occurs during pregnancy, but it is not directly related to threatened abortion. Women with a history of threatened abortion may be at increased risk of gestational diabetes due to underlying hormonal imbalances, but it is not a direct consequence.
* **Option C:** Preeclampsia is a condition characterized by high blood pressure and proteinuria during pregnancy. While it is a possible complication of pregnancy, it is not directly related to threatened abortion.
**Clinical Pearl / High-Yield Fact**
Women who experience threatened abortion are at increased risk of developing preterm labor, which can be prevented or delayed with progesterone supplementation. A 2003 Cochrane review found that progesterone supplementation reduced the risk of preterm birth by 45%.
**Correct Answer:** D.