Bacterial vaginosis is the most common vaginal infection in women of reproductive age and it increases the risk of preterm labor.It is caused by an imbalance of the normal vaginal flora and can lead to intra-amniotic infection, which can trigger inflammation and uterine contractions.

Choice B. Candidiasis is wrong because it is a fungal infection that does not increase the risk of preterm labor.

It can cause itching, burning, and discharge, but it does not affect the amniotic fluid or the fetus.

Choice C. Gonorrhea is wrong because it is a bacterial infection that can cause pelvic inflammatory disease, which can increase the risk of preterm labor, but it is not as common as bacterial vaginosis.

Gonorrhea can also cause neonatal conjunctivitis if transmitted during delivery.

Choice D. Syphilis is wrong because it is a bacterial infection that can cause congenital syphilis if transmitted during pregnancy, but it does not increase the risk of preterm labor.

Syphilis can cause serious complications such as stillbirth, neonatal death, or neurologic damage.

Preeclampsia.Preeclampsia is a condition that can cause placental abnormalities that can lead to pre-term labor.Preeclampsia is characterized by high blood pressure and proteinuria in pregnant women after 20 weeks of gestation.

Preeclampsia can affect the blood flow to the placenta and cause placental insufficiency, which is a reduced ability of the placenta to deliver oxygen and nutrients to the fetus.Placental insufficiency can trigger pre-term labor as a way of protecting the fetus from further hypoxia and growth restriction.

Choice A. Diabetes mellitus is wrong because diabetes mellitus does not directly cause placental abnormalities

Cervical length of less than 2.5 cm.This can indicate cervical insufficiency, a condition in which the cervix begins to dilate and efface prematurely, leading to preterm labor.A normal cervical length is about 4 cm.

Choice A is wrong because cervical dilation of 4 cm or more is not a sign of cervical insufficiency, but rather of active labor.

Choice B is wrong because cervical effacement of 80% or more is also a sign of active labor, not cervical insufficiency.Choice D is wrong because cervical funneling is not a finding that can indicate cervical insufficiency by itself, but rather a complication that can result from it.Cervical funneling is when the internal os (the opening of the cervix inside the uterus) widens while the external os (the opening of the cervix outside the uterus) remains closed.

The client should limit their physical activity and stress as much as possible, as these are risk factors for pre-term labor.

Some additional explanations are:

• Choice A is correct because smoking and drinking alcohol during pregnancy can increase the risk of pre-term labor and birth, as well as other complications for the mother and the baby.

• Choice B is correct because any signs of vaginal bleeding or fluid leakage can indicate a problem with the pregnancy, such as placenta previa or premature rupture of membranes, which can lead to pre-term labor and birth.

The client should report these symptoms to their provider immediately.

• Choice D is correct because drinking plenty of fluids and eating a balanced diet can help prevent dehydration and malnutrition, which can also contribute to pre-term labor and birth.The client should also avoid caffeine, artificial sweeteners, and foods that may cause foodborne illness.

Normal ranges for gestational age are 37 to 42 weeks.Pre-term labor is defined as regular contractions that result in the opening of the cervix before 37 weeks of pregnancy.Pre-term birth is the delivery of a baby before 37 weeks of pregnancy.

Fetal aneuploidy, which means having an abnormal number of chromosomes, can contribute to pre-term labor.This is because fetal abnormalities are associated with 30% of preterm deliveries.

Choice A is wrong because fetal macrosomia, which means having a large baby, is not a risk factor for pre-term labor.In fact, it may increase the risk of post-term delivery.

Choice C is wrong because fetal distress, which means the baby is not getting enough oxygen or nutrients, is not a cause of pre-term labor, but rather a complication that may occur during labor and delivery.

Choice D is wrong because fetal hydrops, which means having excess fluid in the body tissues, is not a direct cause of pre-term labor, but rather a symptom of other conditions that may affect the baby’s health.

Normal ranges for gestational age are 37 to 42 weeks.Pre-term labor occurs when regular contractions result in the opening of the cervix after week 20 and before week 37 of pregnancy.