Pathophysiology
Summary
Complications during pregnancy present a spectrum of conditions that can have significant implications for both maternal and fetal health.
Ectopic pregnancy occurs when an embryo implants outside the uterus, commonly in the fallopian tubes' ampulla. Risk factors include tubal ligation, diethylstilbestrol (DES) exposure, pelvic inflammatory disease (PID), and endometriosis. It presents with acute abdominal pain and vaginal bleeding. Untreated cases risk fallopian tube rupture and intra-abdominal hemorrhage. Standard treatment is methotrexate.
Gestational diabetes is new-onset diabetes during pregnancy, resolving post-delivery. It arises from increased human placental lactogen (HPL), which elevates insulin resistance. Diagnosis involves an oral glucose tolerance test. Unmanaged cases may progress to type 2 diabetes.
Placenta previa involves placental implantation over the cervical os and manifests as painless vaginal bleeding. It can be either partial or complete, and the risk is elevated with a history of previous C-sections and multiparity. In contrast, placental abruption is the premature placental detachment from the uterine wall, and manifests as abrupt and painful vaginal bleeding. It can also be partial or complete, and the risk is elevated with trauma and a history of hypertension, cocaine use, and smoking. ‘Concealed abruption’ occurs without visible bleeding, but may show a retroplacental hematoma on ultrasound.
Postpartum hemorrhage (PPH) most commonly results from uterine atony, where the uterus fails to contract post-delivery. Coagulopathies like von Willebrand disease and factor VIII deficiency, as well as trauma such as uterine rupture or lacerations can also cause PPH. A serious complications of severe hemorrhage during pregnancy or postpartum is disseminated intravascular coagulation (DIC).
Morbidly adherent placentas are characterized by abnormal placental attachment to the myometrium rather than the endometrium. Placenta accreta involves attachment to the surface of the myometrium, placenta increta involves attachment into the myometrium, and placenta percreta involves attachment through the myometrium into the uterine serosa. These conditions can cause severe postpartum hemorrhage (PPH) during due to the lack of separation of the placenta on delivery.
Hypertensive disorders during pregnancy present a spectrum of conditions with implications for both maternal and fetal health. Preeclampsia is characterized by new-onset hypertension after 20 weeks of gestation, coupled with either proteinuria or end-organ dysfunction. It often manifests with symptoms like headache, vision changes, and peripheral edema. The underlying cause is abnormal placentation, leading to to systemic endothelial dysfunction. Risk factors for preeclampsia include pre-existing diabetes, chronic kidney disease, multiple gestation, older age, and a first pregnancy. Treatment includes IV magnesium sulfate to avert the progression to eclampsia, marked by generalized tonic-clonic seizures.
Gestational hypertension is an isolated elevation in blood pressure managed with medications such as hydralazine, alpha-methyldopa, or labetalol. HELLP syndrome presents with Hemolysis, Elevated Liver enzymes, and Low Platelets, featuring a range of symptoms like microangiopathic hemolytic anemia, low platelet count, and elevated transaminases. It is treated with IV magnesium sulfate to prevent seizures (eclampsia).
Lesson Outline
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FAQs
An ectopic pregnancy occurs when the embryo implants outside the uterus, most commonly in the fallopian tubes. Other possible implantation sites include the ovaries and the abdominal cavity. Risk factors for ectopic pregnancy include a history of tubal ligation, exposure to diethylstilbestrol (DES) in utero, pelvic inflammatory disease (PID), and endometriosis. These conditions can lead to fallopian tube injury, increasing the likelihood of an ectopic pregnancy. Symptoms usually include acute lower abdominal pain and vaginal bleeding. If left untreated, the condition can result in life-threatening complications such as fallopian tube rupture and intra-abdominal hemorrhage.
Gestational diabetes is a form of diabetes that develops during pregnancy and usually resolves after delivery. It manifests as hyperglycemia and is often diagnosed through an oral glucose tolerance test. The condition is linked to elevated levels of human placental lactogen (HPL), a hormone secreted by the syncytiotrophoblast of the placenta. HPL increases insulin resistance in the mother, leading to elevated blood sugar levels if the pancreas cannot compensate with increased insulin secretion. Women with gestational diabetes are at a higher risk of developing type 2 diabetes later in life.
Placenta previa is a condition where the placenta implants over the cervical os, the opening of the cervix. This can lead to painless vaginal bleeding during pregnancy. Risk factors for developing placenta previa include a history of Cesarean delivery and multiple gestations. The condition is usually diagnosed through ultrasound and requires careful medical management to prevent complications.
Placental abruption involves the premature detachment of the placenta from the uterine wall, whereas placenta previa is characterized by the placenta covering the cervical os. In placental abruption, vaginal bleeding is typically painful, and in some cases, the bleeding may be concealed between the fetal membranes and the uterine wall. Risk factors for placental abruption include physical trauma, hypertension, cocaine use, and smoking. The condition can result in painful, prolonged uterine contractions and may be identified on ultrasound as a retroplacental hematoma.
Hypertensive disorders of pregnancy include conditions like gestational hypertension, preeclampsia, eclampsia, and HELLP syndrome, all of which involve elevated blood pressure after 20 weeks of gestation. These disorders can lead to various complications, including proteinuria and signs of end-organ dysfunction such as headaches and vision changes. Preeclampsia, in particular, can cause liver swelling, leading to right upper quadrant pain. Risk factors for developing preeclampsia include pre-existing diabetes, chronic kidney disease, multiple gestations, older age, and being in your first pregnancy. If not managed properly, these conditions can escalate into severe forms like eclampsia, characterized by seizures, and HELLP syndrome, marked by hemolysis, elevated liver enzymes, and low platelets.
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