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To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.ajog.2008.12.011 Byline: Clarissa Bonanno, Ronald J. Wapner Keywords: antenatal corticosteroids; epithelial sodium channels receptors; multiple courses; prematurity Abstract: In 1972, Drs Liggins and Howie published a landmark article demonstrating that antenatal corticosteroids significantly reduced the frequency of respiratory distress syndrome and neonatal mortality. A single course of antenatal corticosteroids has become standard of care for pregnant women at risk for preterm birth. Recent studies have suggested weekly courses of antenatal corticosteroids result in improvement in the acute neonatal condition but have not supported long-term benefit. With greater understanding of the beneficial actions of corticosteroids on the fetal lung, the role for this therapy may expand. In addition to increased surfactant production and secretion, corticosteroids facilitate clearance of fetal lung fluid, as well as other maturational effects. Thus, antenatal corticosteroids may prove valuable in the late preterm period and before elective cesarean delivery at term. Author Affiliation: Division of Maternal Fetal Medicine, Department of Obstetrics and Gynecology, Columbia University Medical Center, New York, NY Article History: Received 20 August 2008; Revised 7 November 2008; Accepted 5 December 2008

A study is conducted to determine whether unscheduled cesarean deliveries have complication rates that vary by shift of occurrence, and morbidities are evaluated by delivery shift hypothesizing that such complications would be more frequent during the night shift (11 PM-7 AM) due to sleep deprivation of staff. Results indicate that though neonatal intensive care unit admissions increase at night, maternal and neonatal complications of cesarean delivery do not increase with delivery during the night shift.

The rate of successful trial of labor after previous cesarean delivery for dystocia is assessed in a large cohort based on the relative birth weights of the two pregnancies. It is likely that increased fetal size relative to previous birth weight plays a significant role in the outcome of a subsequent trial of labor for patients with previous cesarean delivery for dystocia, reducing chances of vaginal delivery.

The success rates of vaginal birth after cesarean (VBAC) delivery, uterine rupture and major maternal/perinatal outcomes are compared between women, with previous cesarean deliveries undergoing trial of labor (TOL) with preterm and term pregnancies, and also maternal and neonatal morbidities in women with preterm pregnancies undergoing a TOL versus repeat cesarean delivery without labor (RCD). The likelihood of VBAC success after TOL in preterm pregnancies is comparable to term gestations, with a lower risk of uterine rupture, and perinatal outcomes are similar with preterm TOL and RCD.

A study was conducted to estimate whether midpregnancy genitourinary tract infection with Chamydia trachomtis is associated with an increased risk of subsequent preterm delivery. The results revealed that the treatment of Chlamydia trachomtis was not associated with a decreased frequency of preterm birth.

A study is carried out to test the hypothesis that maternal asthma symptoms and pulmonary function are related to adverse perinatal outcomes. It is found that lower pulmonary function during pregnancy is associated with increased gestational hypertension and prematurity in the pregnancies of women with asthma, which can be due to inadequate asthma control or factors that are associated with increased asthma severity.

The success rates and risks in women with a twin pregnancy who attempt a trial of labor after cesarean delivery are identified. A trial of labor with twins after previous cesarean delivery does not appear to increase maternal morbidity.

The relationship between chorioamnionitis and its duration to adverse maternal, fetal and neonatal outcomes is examined. Chorioamnionitis is reported to increasingly cause maternal and neonatal morbidity after cesarean at term.

The comparison of the efficacy of inhaled beclomethasone dipropionate to oral theophylline for the prevention of moderate asthma exacerbations requiring medical intervention are described. The use of corticosteroids for moderate asthma during pregnancy is more effective, as it has improved forced expiratory volume expired in 1 second (FEV1), than theophylline.

A study is conducted on 658 women with asymptomatic bacterial vaginosis to determine the time course of the regression of asymptomatic bacterial vaginosis in pregnancy with and without treatment and the probability of spontaneous resolution with placebo. Women undergoing placebo treatment had a significant remission of bacterial vaginosis over ten weeks and the remission is more common when the initial vaginal microbiologic disturbance is less.

Having sexual intercourse during pregnancy does not appear to affect the treatment of bacterial vaginosis or the risk of premature birth, according to two large studies of bacterial vaginosis. Bacterial vaginosis is a bacterial infection of the vagina. Some studies suggest that intercourse during pregnancy increases the risk of premature birth but other studies have not confirmed the association.

Chorionic villus sampling can be safely done at 7 or 8 weeks' gestation, according to a study of 82 Orthodox Jewish women. This procedure is done to diagnose fetal chromosome abnormalities. Orthodox Jewish law forbids an abortion after 40 days from conception.

A fibrin/thrombin-based sealant appears to be more effective than blood platelets in sealing a ruptured fetal membrane. This was the conclusion of researchers who stretched fetal membranes over a syringe filled with amniotic fluid, punctured the membrane, and then injected various sealants into the amniotic fluid.

Multifetal pregnancy reduction from quadruplets or triplets to twins can produce an outcome similar to natural twin pregnancies, according to an analysis of 3,513 cases from 11 hospitals in five countries. The more fetuses there are before the procedure, the worst the outcome will be for the remaining fetuses.

When calculating the rate of vaginal birth after a cesarean (VBAC) delivery, it is best not to count pregnant women who do not qualify for a trial of labor. This will allow doctors to accurately compare the rates of VBAC deliveries from different hospitals.

It may not be necessary to remove a cervical cerclage when a pregnant woman who has one has premature rupture of fetal membranes. Cervical ceclage is a procedure to prevent premature birth by keeping the cervix from opening prematurely.

High levels of fetal fibronectin in a pregnant woman's vagina is a risk factor for premature birth, according to a study of 13,360 women. Fetal fibronectin is a protein produced by the fetus.

It appears possible to abort one fetus in a twin pregnancy without harming the remaining fetus, according to an international study of 402 such cases. Most often this is done because one of the fetuses has a severe birth defect and is not expected to live.

Cerclage does not appear to prevent premature labor. During this technique, a ring is placed around the cervix. In a study of 168 pregnant women, transvaginal ultrasound was effective in identifying those at risk of premature labor.

Fetal cells may change their antigens as the fetus grows. Antigens are proteins on the surface of every cell. Researchers studied the expression of certain antigens on fetal cells taken from fetal blood. The expression of some of the antigens analyzed declined as the fetus grew older. This means that tests for those antigens would not be able to detect the cells. And that in turn means doctors would not be able to detect fetal cells in the mother's blood. Testing fetal cells in the mother's blood for genetic abnormalities is a non-invasive method for detecting these genetic disorders.

Second trimester ultrasound scan measurements appear to be a more reliable means of identifying women at risk for delivering prematurely than measurements done during a physical examination. Cervical length measurements using both ultrasound and physical examination were taken between 14 and 30 weeks of pregnancy in 96 high-risk women. Women with a cervix shorter than 25 millimeters as measured by ultrasound were 4.8 times more likely to deliver prematurely than were those with a longer cervix. Manual cervical measurements were not significantly different between full-term and pre-term pregnancies.

Selective reduction of multifetal pregnancies may not reduce the risk of gestational growth restriction in the remaining fetuses. Researchers compared the birth weights and gestational ages from twin pregnancies that had been reduced from triplet, quadruplet, or more pregnancies to those of twins from unreduced pregnancies. Intrauterine growth restriction was greatest in the remaining twin fetuses from quintuplet or higher pregnancies, with the growth of these twins 50% that of a normal single birth. Intrauterine growth restriction was 19.4% in unreduced twins, 36.3% among triplet pregnancies reduced to twins, and 41.6% in twins reduced from quadruplet pregnancies. Measures should be taken by assisted reproduction providers to avoid multifetal pregnancies in the first place.

A home uterine activity monitoring device appeared to allow earlier diagnosis of labor and prolongation of pregnancy among women at high risk for preterm labor. This was true even without daily nursing contact, which has been suggested as the underlying reason behind the apparent effectiveness of home uterine activity monitoring. A group of 187 women with prior preterm birth were randomly assigned to a home uterine activity monitor or to standard instruction in diagnosing contractions. Monitored women were taught to use the monitor and transmitted data to a central station. Twenty-four percent of monitored women and 22% of control women experienced preterm labor. However, the average cervical dilation at time of diagnosis was 1.7 cm in the monitored group versus 2.8 cm among control women. Average duration of pregnancy after diagnosis among monitored women was 21 days versus 3 days among control women. The earlier labor is diagnosed, the more likely medication to suppress labor is to succeed.

Selective termination of an abnormal twin fetus or multiple fetuses in a dizygotic (fraternal) pregnancy may be safely performed by an experienced physician with injections of potassium chloride. A multicenter study of 180 fetuses that were selectively aborted correlated early gestational age at the time of the procedure with a low loss rate and with an older gestational age at birth. The study also found that the air embolization method of abortion was riskier for the surviving fetus(es) than was potassium chloride injection. Losses occurred every time for both twins when selective termination was performed to a twin of a monochorial pregnancy, in which the twins shared the same placenta. Genetic prenatal diagnosis should be performed as early as possible, using chorionic villus sampling rather than waiting to do amniocentesis. Thus, if selective termination is chosen, it can be performed early in the pregnancy. Exact identification of the fetus(es) to be aborted is also necessary, to avoid accidentally aborting the healthy fetus.

Most fetuses with a normal karyotype who have a cystic hygroma in the first trimester will be normal at birth. A cystic hygroma is a fluid-filled cyst on the back of the neck. Karyotype is the full chromosome set of a cell nucleus. Cystic hygroma in the second trimester is highly associated with genetic defects and only 2% to 3% of affected fetuses survive and are normal. In contrast, among 43 fetuses with cystic hygroma diagnosed in the first trimester, 51% were found to have normal genetic karyotype on chorionic villi sampling, and the hygroma disappeared by 16 weeks' gestation in most cases. Of the 22 fetuses with normal karyotype, 16 were born alive, four were elective terminations, and two were fetal deaths. Fifteen of the liveborn infants were examined by a geneticist between six weeks and 35 months of age, of whom three (20%) had abnormal features and one appeared to have Noonan's syndrome, an inheritable genetic defect. The rest were normal in appearance and behavior.

A multifetal pregnancy may be managed safely and effectively by either transabdominal or transvaginal methods of pregnancy reduction. Fertility drugs or assisted reproductive techniques sometimes result in multifetal pregnancies. In order to improve the chances of a successful pregnancy and healthy infants, one or more fetuses may be eliminated by pregnancy reduction. The transabdominal technique involves inserting an ultrasound-guided needle through the abdomen into the fetal heart and injecting a fatal substance. Transvaginal techniques involve either the same sort of injection through the vagina or disruption and aspiration of the embryo. Of 1074 pregnancy reductions studied, 846 used the transabdominal technique and 238 used transvaginal techniques. The miscarriage rate for transvaginal procedures was 13%. For the transabdominal procedure, the miscarriage rate improved over time from 16% to just under 9%. More than 84% of pregnancies reduced by either technique were carried to 33 weeks' gestation or longer.

Reduction of a triplet pregnancy to a twin pregnancy may decrease the risk of perinatal complications or death. Perinatal is pertaining to or during the period shortly before and after birth. Among 124 sets of triplets or twins delivered between Jul 1988 and Jul 1992, 47 were triplets reduced to twins, 14 were nonreduced triplets and 63 were nonreduced twins. The reduced triplets were delivered after an average of 36 weeks of pregnancy, compared with after an average of 31 weeks for the nonreduced triplets. The number of deaths during the perinatal period was seven times lower among the reduced triplets that among the nonreduced triplets. No significant difference in the number of complications or deaths was found between the reduced twins and the nonreduced twins. The practice of pregnancy reduction may raise certain moral and ethnical questions.

Simple hygroma in the first trimester of pregnancy may be an indicator of chromosomal abnormality and should be monitored. Cystic hygromas are fluid-filled cysts at the back of the neck that arise from defects in the development of the lymphatic vessels. The lymphatic and venous systems do not connect as they should and fluid accumulates at the back of the neck. Following ultrasound testing, 68 fetuses were diagnosed with cystic hygroma and underwent DNA analysis. Twenty-seven of the fetuses had a normal set of chromosomes. Trisomy 21, which occurs when there is an extra copy of chromosome 21, was the most common abnormality among the 41 fetuses with chromosomal disorders. In 23 of the fetuses with normal chromosome sets, the hygromas resolved before birth.

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.ajog.2004.03.038 Byline: Thomas M. Jenkins (a), Anthony C. Sciscione (b), Ronald J. Wapner (b), Gloria E. Sarto (a) Abstract: This study was undertaken to assess training availability, methods, and plans for future practice of invasive procedures for maternal fetal medicine (MFM) fellows. Author Affiliation: (a) Divisions of Maternal-Fetal Medicine, University of Wisconsin-Madison, Madison, Wis (b) Drexel University College of Medicine, Philadelphia, Pa Article History: Received 16 June 2003; Revised 22 January 2004; Accepted 11 March 2004 Article Note: (footnote) Reprints not available from the authors.

Removing an intrauterine contraceptive device (IUD) from a pregnant woman can be accomplished around the same time as chorionic villus sampling (CVS). There is increased risk of miscarriage and infection if an IUD is left in during a pregnancy. CVS is a late first trimester procedure that removes a bit of the placenta for genetic analysis. Six pregnant women had an IUD with no visible string. Under ultrasound imaging guidance, an IUD hook was passed through the cervix to snag the IUD and retrieve it. Four women had CVS at the same time as the IUD removal, and two were scheduled for separate procedures. Two women had miscarriages; one was believed to be due to a nonviable pregnancy, but the other occurred within one day after the procedure. The other four women gave birth to healthy, full-term infants.

Byline: Ronald J. Wapner, Michael G. Ross Author Affiliation: Department of Obstetrics and Gynecology, Jefferson Medical College, Ben Franklin House, 834 Chestnut St., Suite 400, Philadelphia, PA 19107 Department of Obstetrics and Gynecology, Harbor - University of California, Los Angeles, Medical Center, 1000 W. Carson St., Box 3, Torrance, CA 90509