Fetal laser surgery in genetic polydactyly mice

The first digital ray of the hindlimb plate in Slc:ICR mouse fetus was irradiated with 2 watts argon laser beam for 0.3 sec after releasing from the abdominal cavity and envelop of uterine myometrium on day 13 of gestation, and then the fetuses were allowed to develop in the abdominal cavity contacting with the uterus via the placenta exo utero until term. ICR mouse fetuses which received fetal laser surgery lost their first digits completely, resulting in 4-digit hindfoot on day 18 of gestation. The homozygous Polydactyly Nagoya (Pdn/Pdn) mice exhibit 1-3 extra digits both in the fore- and hindlimbs preaxially. The extra digital rays in the left hindlimbs of Pdn/Pdn fetuses were irradiated with 2 watts argon laser beam for 0.3 sec on day 13 of gestation exo utero. The left hindlimbs of the Pdn/Pdn fetuses which received fetal laser surgery lost their preaxial extra digits on day 18 of gestation, resulting in 5 digits, though their 1st digit was triphalangia. The combination of a laser instrument with the fetoscope and/or ultrasound scanner may promote the fetal surgery of congenital anomalies in humans.     

Fetal ultrasonography.

Since its introduction in the 1950s, ultrasonography in pregnancy has been helpful in determining gestational age, detecting multiple pregnancies, locating placentas, diagnosing fetal anomalies, evaluating fetal well-being, and guiding obstetricians with in utero treatment. We review current standards and controversies regarding the indications, safety, accuracy, and limitations of ultrasonography in pregnancy.     

Fetal drug therapy.

Fetal drug therapy encompasses several areas, including the prevention of external genital masculinization in 21-hydroxylase deficiency syndrome (congenital adrenal hyperplasia), biochemical amelioration of methylmalonic acidemia, and biotin-responsive multiple carboxylase deficiency. The correction of cardiac arrhythmias has become relatively commonplace, and a reduction in the risks of neural tube defects is now possible with the use of preconceptual and early conceptual folic acid. Similarly, fetal function can be altered by the induction of fetal lung maturity using a number of agents; corticosteroids are the most common fetal pharmaceutic agent, and a number of other agents have also been tried. The most common route of administering pharmaceutic agents is through the mother and the placenta, although the direct administration of certain agents is becoming more common.     

Fetal complications of obstetric cholestasis.

Among 56 pregnancies complicated by obstetric cholestasis five intrauterine deaths and one neonatal death occurred between 33 and 39 weeks, and a further six infants required urgent delivery for intrapartum asphyxia. Eighteen spontaneous premature deliveries occurred. Five mothers required specific treatment for unexplained postpartum haemorrhage. Cholestasis of pregnancy is therefore not a condition benign to the fetus, and it may contribute to increased maternal morbidity.     

Fetal exsanguination associated with antepartum hemorrhage.

Fetal bleeding in utero is infrequent. It is usually life-threatening but can be treated successfully in most cases if recognized early. Four cases are described and it is suggested that screening for fetal blood be done in all instances of antepartum hemorrhage.