What to expect when you're expecting (211 page)

How common is it?
Four to 8 percent of pregnant women are diagnosed with oligohydramnios during their pregnancy, but among overdue women (those two weeks past their due dates), the number rises to 12 percent. Women with a post-term pregnancy are most likely to have oligohydramnios, as are those who have premature rupture of membranes.

What are the signs and symptoms?
There are no symptoms in the mother, but signs that would point to the condition are a uterus that measures smaller than it should and a decreased amount of amniotic fluid, detected via ultrasound. There might also be a noticeable decrease of fetal activity and sudden drops in the fetal heart rate in some cases.

What can you and your practitioner do?
If you’re diagnosed with oligohydramnios, you’ll need to get a lot of rest and drink plenty of water. The amount of amniotic fluid will be closely monitored. If at any point oligohydramnios endangers the well-being of your baby, your practitioner may suggest amnioinfusion (in which fluid levels are augmented with sterile saline) or may opt for an early delivery.

What is it?
Too much amniotic fluid surrounding the fetus causes the condition known as hydramnios (also called polyhydramnios). Most cases of hydramnios are mild and transient, simply the result of a temporary change in the normal balance of the amniotic fluid production, with any extra fluid likely to be reabsorbed without any treatment.

But when fluid accumulation is severe (which is rare), it may signal a problem with the baby, such as a central nervous system or gastrointestinal defect, or an inability to swallow (babies typically swallow amniotic fluid). Too much amniotic fluid can put your pregnancy at risk for premature rupture of membranes, preterm labor, placental abruption, breech presentation, or umbilical cord prolapse.

How common is it?
Hydramnios occurs in 3 to 4 percent of all pregnancies. It is more likely to occur when there are multiple fetuses and can be related to untreated diabetes in the mother.

What are the signs and symptoms?
More often than not, there are no symptoms at all with hydramnios, though some women may notice:

Difficulty feeling fetal movements (because there’s too much of a cushion)

Unusually rapid growth of the uterus

Discomfort in the abdomen

Indigestion

Swelling in the legs

Breathlessness

Possibly, uterine contractions

Hydramnios is usually detected during a prenatal exam, when your fundal height—the distance from your pubic bone to the top of your uterus—measures larger than normal, or during an ultrasound that measures the amount of fluid in the amniotic sac.

What can you and your practitioner do?
Unless the fluid accumulation is fairly severe, there’s absolutely nothing you need to do except to keep your appointments with your practitioner, who will continue to monitor your condition. If the accumulation is more severe, your practitioner may suggest you undergo a procedure called therapeutic amniocentesis, during which fluid is withdrawn from the amniotic sac to reduce the amount. Since hydramnios puts you at increased risk for cord prolapse, call your practitioner right away if your water breaks on its own before labor.

What is it?
PPROM refers to the rupture of the membranes (or “bag of waters”) that cradle the fetus in the uterus, before 37 weeks (in other words, before term, when the baby is still premature). The major risk of PPROM is a premature birth; other risks include infection of the amniotic fluid and prolapse or compression of the umbilical cord. (Premature rupture of the membranes, or PROM, that isn’t preterm—that is, it takes place after 37 weeks, but before labor begins—is discussed on
page 363
.)

How common is it?
Preterm premature rupture of membranes occurs in fewer than 3 percent of pregnancies. Women most at risk are those who smoke during pregnancy, have certain STDs, have chronic vaginal bleeding or placental abruption, have had a previous early membrane rupture, have bacterial vaginosis (BV), or who are carrying multiples.

What are the signs and symptoms?
The symptoms are leaking or gushing of fluid from the vagina. The way to tell whether you’re leaking amniotic fluid and not urine is by taking the sniff test: If it smells like ammonia, it’s probably urine. If it has a somewhat sweet smell, it’s probably amniotic fluid (unless it’s infected; then the fluid will be more foul smelling). If you have any doubts about what you’re leaking, call your practitioner to be on the safe side.

What can you and your practitioner do?
If your membranes have ruptured after 34 weeks, you’ll likely be induced and your baby delivered. If it’s too soon for your baby to be delivered safely, chances are you’ll be put on in-hospital bed rest and be given antibiotics to ward off infection, as well as steroids to mature your baby’s lungs as quickly as possible for a safer early delivery. If contractions begin and the baby is believed to be too immature for delivery, medication may be given to try to stop them.

You’ll Want to Know …

With prompt and appropriate diagnosis and management of PPROM, both mother and baby should be fine, though if the birth is premature, there may be a long stay in the neonatal intensive care unit for baby.

Rarely, the break in the membranes heals and the leakage of amniotic fluid stops on its own. If that happens, you’ll be allowed to go home and resume your normal routine while remaining on the alert for signs of further leakage.

Can it be prevented?
Vaginal infections, particularly BV, can lead to PPROM; therefore, watching out for and treating these infections may be effective in preventing some cases of PPROM.

What is it?
Labor that kicks in after week 20 but before the end of week 37 of pregnancy is considered to be preterm labor.

How common is it?
Preterm labor is a fairly common problem; about 12 percent of babies are born premature in the United States.

Risk factors leading to premature labor include smoking, alcohol use, drug abuse, too little weight gain, too much weight gain, inadequate nutrition, gum infection, other infections (such as STDs, bacterial vaginosis, urinary tract infections, amniotic fluid infection), incompetent cervix, uterine irritability, chronic maternal illness, placental abruption, and placenta previa. Women who are younger than 17 or older than 35 years old, those who are carrying multiples, and those with a history of premature delivery are also at increased risk. Preterm births are also more common among African American and disadvantaged women. In addition, a fairly large number of premature labors are induced by practitioners in an appropriate response to a medical condition that requires an early birth, such as preeclampsia or PPROM.

Still, much more needs to be learned about what causes labor to begin early; at least half of the women who go into preterm labor have no known risk factors.